Stella 2T highway/performance upgrades
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Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Tue Oct 22, 2019 12:51 am quote
If you are sure about that stroke, then you need to compensate to get the timing back up. Seems quite short though. 59.8 is about the shortest usually seen.

Based on 59.67 stroke and keeping 125 as the traget for the transfers. PBT should be 0.40mm under or as near as 2.0mm packer gets it. Exhaust up to 33.20mm will make quite an exciting ride.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Tue Oct 22, 2019 2:53 am quote
Is there a more accurate way to measure the stroke?

Last edited by swiss1939 on Tue Oct 22, 2019 8:25 am; edited 1 time in total
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Tue Oct 22, 2019 8:06 am quote
Jack221 wrote:
If you are sure about that stroke, then you need to compensate to get the timing back up. Seems quite short though. 59.8 is about the shortest usually seen.

Based on 59.67 stroke and keeping 125 as the traget for the transfers. PBT should be 0.40mm under or as near as 2.0mm packer gets it. Exhaust up to 33.20mm will make quite an exciting ride.
Yesterday, I was measuring by using one hand to hold the crank at BDC and turn to TDC, while using the other hand to place/set the caliper into the bore and zero out the display by holding the caliper on the end into the bore with one finger while zeroing out the display with another finger stretched way out to reach the zero button. Kinda inaccurate way to do a measurement. So today, I had a neighbor who was outside help me remeasure the stroke. He held and turned the crank while I was able to precisely, using two hands, hold and set the caliper for accurate measurements. What I got after three measurements is 59.86mm.

I also remeasured transfer ports in multiple places, both ports closest to exhaust on either side of exhaust, over 6 measurements to get new number of 47.04mm

How does that change your numbers?

I believe this means I use 1.5 base gasket keeping pbt at zero and grind exhaust to 32.8mm. This gets
186/126 with 30 blowdown and 1.14mm squish that I can leave without decking head.

Cross referencing these numbers to this site that I found:
https://martysgarage.info/reference/two-stroke-port-duration/
I think the results of these timings/blowdown is somewhere around an ~9000 RPM limit.

EDIT: updated this post with new transfer port measurement and changed all my numbers to match
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Tue Oct 22, 2019 3:20 pm quote
I traced the ports on paper like everyone seems to do. Figured this would be an easy way to confirm or deny my physical measurements and get a more accurate number. Front (red crayon) side, I measured using my same calipers from top of paper (flush with top of cylinder) to top of each port. This confirmed my previous measurements in last post.

I then scanned both sides of the paper into photoshop and used the measurement tool to try to be more accurate and the results I got are:

exhaust: 34.92184069 mm
transfer: 47.03174872 mm

The transfer times are much better at 126 by default (in either the digital or analog measurement) meaning all I need to do is grind exhaust to 32.8mm get a sporty 186.

For some reason I am really confused by arc and chord. What math am I doing with the resultant numbers and what does it provide insight for?

Most accurate measurements to date:

stroke: 59.86mm
exhaust: 34.92mm or 35.15mm (doesn't really matter which one as they are either 177 or 178 time which will get ground up to 186 anyways).
transfer: 47.03-47.04mm (both are 126 at zero deck anyways).
arc: 36.96440054 mm
chord: 32.52 mm (don't think this is totally accurate).

Measuring the chord by stretching tape over it and marking edges seems very inaccurate. It is a good fast way to do it, but very hard to be precise. I tried it like 5 different times and its hard to be accurate with how taught you stretch the tape across, or how clean you mark edges especially when you don't have a fine point marking tool. There has to be a better tool to do that measurement? Maybe dial gauges for measuring bore? Something like this?
https://www.harborfreight.com/6-piece-telescoping-gauge-set-5649.html

mal166ports_01.jpg

mal166ports_02.jpg
back side which just got oil transferred on from pressure seemed easier and more precise to read.

mal166_timings_20191022.jpg

Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Wed Oct 23, 2019 5:16 am quote
Would try to keep the transfers down to 125 if you can. 186 will be ok as long as the carb is big enough.

Arc width of exhaust can safely go to 42mm with 1mm rings. Quite a lot of grinding to do there. Would get all that done before its bored.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 23, 2019 5:22 am quote
Jack221 wrote:
Would try to keep the transfers down to 125 if you can. 186 will be ok as long as the carb is big enough.

Arc width of exhaust can safely go to 42mm with 1mm rings. Quite a lot of grinding to do there. Would get all that done before its bored.
+0.1mm added to the pbt would get to 185/125. Please tell me it's as simple as adding a 0.1mm head gasket?! This would then become 1.24mm squish.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Thu Oct 24, 2019 10:42 am quote
I bought a set of harbor freight telescoping gauges and micrometers to remeasure the chord of the exhaust and take measurements of the bore size and both old and new piston diameters.

https://www.harborfreight.com/Micrometer-Set-3-Pc-64202.html

https://www.harborfreight.com/6-piece-telescoping-gauge-set-5649.html

I hope I am correct in that using a telescoping gauge inside the exhaust port to measure maximum width at the cylinder wall gives the chord measurement in the same but more accurate way to the tape trick suggested earlier.

My new chord measurement for the exhaust port is 35mm even which seems more correct compared to the 32.5mm ballpark using tape. This new number is closer to the accurate Arc measurement which I assumed the chord would not be so drastically different from.

My measurements for the current bore diameter as well as both pistons are as follows:

Using Digital caliper...
Bore: 60.95mm
Stock piston: 60.75mm
First over piston: 61.2mm

Using micrometer and gauge...
Bore: 60.96mm
Stock piston: 60.77
First over piston: 61.12mm
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Location: california
Thu Oct 24, 2019 1:41 pm quote
Swiss - after a number of rounds of measuring using the various methods, I tried this.
- measure ring thickness.
- slide ring in to cyl to top of port as shown - I used piston to push it level - and press it back to exact after I passed the top of the port.
- measure down - making sure not to bump ring hard enough to move it.

To set the ring exactly at the height, with no chamfer having any effect, I used a flashlight and a magnifying glass (actually - I had readers on, AND used a magnifying glass).

I found it allows me remarkable precision and repeatability.
Might try it just for fun if you have interest to experiment.

-CM

IMG_1957.JPG

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Thu Oct 24, 2019 5:58 pm quote
Oh boy. Big box came today! Christmas in October. Also nearly finished with another side project that took me away from the engine rebuild.. last coat of lacquer on my computer table after sanding the worn out 10 yr old lacquer and stain job. 3 new layers of stain and 3 layers of lacquer over the past two weeks. Just gotta sand the surface down tomorrow and polish it shiny and that table taking up my whole garage will finally be out to make space for the engine rebuild!

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All the remaining main bits for rebuild. Plus a lot of random hardware I stuff my order with to make shipping from Germany worthwhile

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and this project sidetracked me for 3 weeks. finally finish setting up computer equipment in new apartment and make space in garage to continue engine rebuild!

Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Thu Oct 24, 2019 10:54 pm quote
Forget about measuring chord and just measure arc. Max arc to aim for is 42mm. This includes any chamfer (that shouldn't be there) on the sides.
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Thu Oct 24, 2019 10:55 pm quote
wow Swiss1939 looks like you've been a good boy what is the shock? Table looks great!
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Fri Oct 25, 2019 5:19 am quote
Jack221 wrote:
Forget about measuring chord and just measure arc. Max arc to aim for is 42mm. This includes any chamfer (that shouldn't be there) on the sides.
No Problem, Jack. Was content in my previous arc measurement and your 42mm target for grinding. Only messing with the chord measurements cause I didn't have space yet to start grinding with table in the way. Was curious about the difference in measurement techniques.
hibbert wrote:
wow Swiss1939 looks like you've been a good boy what is the shock? Table looks great!
Shock is SIP Performance 2.0
https://sip-scootershop.com/en/products/shock+absorber+sip+performance+_76001rtb

I've had them in my notepad for a year waiting to purchase cause they are expensive. And finally got the rear. Still need a front shock to replace the bitubo currently on there. And for some reason, everything I have had on my list to purchase for a year is all going out of stock and discontinued all at the same time. Extremely frustrating. The front shock in same color Titanium black 76001FBB is out of production and no longer in stock. So I gotta have a mismatch shock scheme going on! Although I might try this BGM for the front for a near match (with some silver in there for some reason). https://www.scooter-center.com/en/front-shock-absorber-bgm-pro-sc/f16-competition-240mm-vespa-px80-px125-px150-px200-t5-125cc-bgm7781?number=BGM7781
The titanium from sip on front and rear would have went perfectly on the maroon p200 project, but this may be the closest I can get for now unless SIP makes a v3.0 in same color. I am throwing these on the stella for now to test them out since the stella will be running long before the p200.

The Malossi 166 MK III is discontinued right before I seized this one. It would have been cheaper to buy a whole new kit instead of the first over piston and re-bore, but damn Malossi for discontinuing it for some reason. And finally, I've been waiting to buy the BGM Super strong clutch with CR80 plates for 22/68 tooth gearing for 5 months and that is out of stock/discontinued until the updated v2.0 is produced. I try to buy parts on my list here and there so I'm not doing one big sticker shock, but my luck apparently leads to out of stock/discontinued on everything.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Fri Oct 25, 2019 10:11 pm quote
Also just noticed that the short 4th drt gear I got was not for this engine, but for the p200e on old lusso gear box. Mixed it into my shopping list for this engine a month ago and when I went around to buy everything I forgot and thought it was for this new lusso gear box. Oh well. It will be there for other project!
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Sun Oct 27, 2019 4:08 pm quote
Lots of work done today finally! About 2-2.5 hrs of grinding max. First time, very careful.

Matched the case and gasket to cylinder (still need to match the cylinder to the case and gasket).

I followed the method that Lee @thatscooterthing does to match the cases to the cylinder. I covered the base gasket in sharpie around the port edges as well as around the port openings on the case and installed the 1.5mm base gasket needed for zero deck with sharpie face down toward inside of engine then installed the cylinder without torque onto each side of case separately. I then used a dentist metal pick to scratch the outline of the cylinder port opening into the sharpie marks on the case and the gasket. This gives me a rough outline for a one way match cylinder to gasket and case. I then dremeled a profile on the case port openings starting with the inner port areas nearest the crank then working back towards the gasket surface to profile the port opening and surface on both sides of case to match that first rough outline.

Once I roughed that out and was satisfied, I then dremeled the gasket to match the cylinder, many revisions comparing gasket to the cylinder and checking with the dentist pick until there was no lip from the cylinder being wider than the gasket. This then needs to be re-matched to the case to profile the face of the port openings where they meet the cylinder and gasket. A few more rounds of grinding the case port openings to profile the face and then I was confident the case would match the cylinder and gasket perfectly.

The only thing left to do is to take the gasket profile (which is the combination of both the case and the cylinder profiles) and match the cylinder to that. This I have not done yet because I want to confirm that I can widen the large base ports on the cylinder walls that feed from the crank without affected the port timings/etc. This is because the large cylinder port openings that feed from the carb are not as wide as the case, causing flow to be interrupted. Once I do this profiling of the cylinder, both at the gasket face to match the gasket, and along the large side wall openings, then all 3 surfaces will be well matched for optimum airflow.

The other question I was wondering is if it is safe and better to profile the curved area where the carb feeds into the crank on the case and smooth out all those corners/edges? I feel like I've seen FMP and thatscooterthing do that but just wanted to confirm this will not have any adverse affect on the crank or the timing.

This process of case matching/profiling with a dremel is where I am in my element, compared to jetting which still feels like i'm a rookie lost in the woods. Dremeling and shaping metal is in line with my art background as I did a lot of sculptural work in undergrad.

EDIT: just measured the cylinder large side port width to see if widening it to match the case will be too large for the piston rings max exhaust arc of 42mm Jack suggested. Those large side ports are 32.5mm wide each on both sides of the cylinder wall. Im wondering if widening both of them another 3-6mm would matter as its still under the max arc, but because they are both at the same position in the barrel, does that affect the piston rings in any way?

IMG_20191027_162509.jpg
just starting the profile on the clutch side of case. Original case profile on left still.

IMG_20191027_165024.jpg
more of the port profiling, starting in the rear closest to crank and working towards the gasket face.

IMG_20191027_163933.jpg
once I profiled the rear of the case port, the cylinder mounted shows it is a smooth transition on this side of the large cylinder wall port, and at the rear closest to the crank.

IMG_20191027_163924.jpg
on this side of the same cylinder wall port, you can see the cylinder wall is not wide enough to match the case. this is where I need to widen the large cylinder ports and want to make sure its not going to be a critical mistake to do so.

IMG_20191027_164045.jpg
the top transfer port took the slightest bit of dremel on one side to get a really seamless
match.

IMG_20191027_170017.jpg
this is the outside of the cylinder wall with markings for where the cylinder overlaps the case opening. this is what needs to be removed to match the cylinder on both ports.

IMG_20191027_170029.jpg
and the other side port. marked with both the cylinder wall area that needs to be widened, and the gasket face area that needs to compliment that profile.

IMG_20191027_171540.jpg
this curved area below the reed valve, its cool to grind a more improved profile all around the sharp edges without screwing anything up?

IMG_20191027_171500.jpg
rough profile on the flywheel side port.

IMG_20191027_173030.jpg
after profiling both sides of the case. you can see where the gasket was not wide enough for the original opening of the case ports. sharpie and outline that to grind the gasket to match the case.

IMG_20191027_180139.jpg
now that the gasket is roughed out for both, I still needed to remove any lips on the gasket to the cylinder. You can also see where the cylinder side ports need to be profiled to match the gasket surface.

IMG_20191027_180237.jpg
and same on the other side.

IMG_20191027_180640.jpg
overall view of the same stage.

IMG_20191027_181607.jpg
refining the profile of the gasket to cylinder, by marking just the areas that are still lips overlapping the cylinder. hit those spots with dremel to match the two surfaces.

IMG_20191027_182626.jpg
now that the gasket has been fully profiled to the case first and now the cylinder. you can see the fine tuning required to further match the case to cylinder. lots of back and forth matching everything to each other.

IMG_20191027_182841.jpg
outline of where the finished profile of the gasket shows where the case face needs to be widened to perfectly match the cylinder.

IMG_20191027_182849.jpg
and the same on the other side. you can see there is still a bit of widening the case faces to match cylinder in a few spots.

IMG_20191027_185023.jpg
and now the cases are finely matched in one direction from cylinder to case.

IMG_20191027_185033.jpg
as you can see from this closeup. gasket and case walls line up cleanly.

IMG_20191027_185041.jpg
same on the other side. Yes there is one small spot in the top corner that could be worked a little. I will deal with that with sandpaper and polish as I don't want to go too far.



Last edited by swiss1939 on Sun Oct 27, 2019 8:20 pm; edited 3 times in total
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Sun Oct 27, 2019 4:08 pm quote
one last image related to previous post cause i reached the 20 image limit per post.

There was plenty of wall thickness on the cases for the profiling required with these Malossi 166mkIII cylinders! I did not even bother with jb weld layer of protection on the opposite sides to where I was grinding.

IMG_20191027_185326.jpg
and the final view of the case matching complete. still need to smooth and polish those surfaces.. as well as finish matching the cylinder to this where overlaps were shown previously.

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Sun Oct 27, 2019 5:00 pm quote
Something completely unrelated to grinding and profiling. I was also taking a closer look at the DRT short 4th gear I bought on SIP because I noticed the other night it said old lusso on the item page, but the descriptor also says px compatibility. This got me wondering if this gear is really only for the old lusso drive shafts or if it is somehow compatible with both the old and new gearboxes.

https://sip-scootershop.com/en/products/gear+cog+36+teeth+4th+gear+_40432910

The gear came with some instructions and an extra circlip that I was not sure why it was included. Instructions from DRT are in Italian, if any Italians on here could help describing what the instructions say? After taking closer look at the gear, measuring the inner gear thickness on both the old lusso 4th gear I have and the new stella 4th gear I have.. and looking at the graphics on the drt instructions, I "think" this gear might by compatible with both gearboxes. What I noticed is the new gearbox gears have a thicker inner gear tooth with one side indented and the other side flush with the outer edge of the gear. The old gears have a thinner inner gear tooth with one side matching the indentation of the new gears, and the other side that is flush on new gears, has a smaller indentation on the old gears. This DRT gear's inner tooth thickness is basically in-between the thickness of the old gear and new gear inner teeth. After comparing all 3 gears and measuring the thicknesses of those inner teeth, that got me wondering why the DRT gears inner tooth is thicker than the old lusso gear if it is supposed to be for the old lusso gearbox. So i pulled the included circlip out and started looking at that. What I immediately noticed is that when that circlip was placed on the DRT gear in the proper spot, it effectively removed that small indentation and made that side of the gear perfectly flush with the included circlip. Doing that and seeing it flush with the gear surface gave me a thought.. maybe these DRT gears are compatible with both.. without the included circlip, it would be installed on an old lusso gearbox.. and with the included circlip it would be installed on a new gearbox as it no longer has two sides with indents but matches one side flush where the circlip and spacer would go on the original new gearbox.

Anyone have thoughts about if this assumption is correct? Or is there some other aspect of the old lusso gears that would prevent them from working in a new gearbox that I am not accounting for? I'm thinking if you mount the drt gear on the new gearbox axle with the drt included circlip to make that gear side flush, then install the normal circlip and/or spacer that would normally be installed on the new gearbox axle against the flush side of the 4th gear.

new gearbox 4th gear inner tooth, spacer and circlip total thickness is: 8.53mm

DRT 4th gear with included circlip and the LML circlip total thickness is 8.62mm

IMG_20191027_141641.jpg
DRT short 4th gear.

IMG_20191027_141656.jpg
DRT gear has a small indented side where the new gearbox inner teeth are flush with the gear wall.

IMG_20191027_141705.jpg
the other side of the DRT has the normal width indentation that both old and new gearbox gears have.

IMG_20191027_141715.jpg
and the DRT gears inner tooth. This thing is thicker than the old lusso gears, but not as thick as thew new gearbox gears.

IMG_20191027_141728.jpg
P200E 4th gear. normal indentation side all 3 gears share.

IMG_20191027_141740.jpg
P200E 4th. Other side has indentation that the new gearbox gears do not have. the DRT gear shares this side indentation.

IMG_20191027_141817.jpg
LML 4th gear. this inner tooth is flush with the gear wall, on this side. Unlike both the P200E and DRT gears.

IMG_20191027_141827.jpg
LML 4th gear. same normal indentation side shared with all 3 gears.

IMG_20191027_141955.jpg
P200E 4th gear inner tooth thickness.

IMG_20191027_142040.jpg
LML 4th gear inner tooth thickness.

IMG_20191027_142129.jpg
DRT short 4th gear inner tooth thickness. in-between the old and new gearbox gears.

IMG_20191027_145013.jpg
the circlip included with the DRT gear.

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the circlip installed on the DRT gear smaller indentation side becomes flush with the outer edge of that gear. just like the LML gear in new gearbox style.

IMG_20191027_145039.jpg
one of the included instructions from DRT. This was the only thing in english.

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the other instruction paper included with DRT gear. In Italian.

IMG_20191027_145103.jpg
same instruction paper in Italian. the other side. this side seems to suggest the spacer is used for cross compatibility between gearbox styles. But I am not sure. Any Italians take a stab at it?

IMG_20191027_145517.jpg
the included DRT spacer thickness.

IMG_20191027_145727.jpg
spacer and inner tooth thickness of DRT gear.

IMG_20191027_150801.jpg
thickness of spacer and circlips normally installed on the new gearbox from my LML/stella.

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Sun Oct 27, 2019 5:14 pm quote
I don't know a thing about the gears but dood the porting looks great!
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Mon Oct 28, 2019 3:08 am quote
Porting does look good. Wouldn't open the skirt out too much, as it won't do anything much without the piston opened out too and this will make it rattle more. not worth the risk in my opinion.

Might get away with an extra spacer on that gear cog but the circlip is not meant to fill that gap. It's just a stronger clip. You'll be able to re-sell it or something.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Mon Oct 28, 2019 7:27 am quote
Jack221 wrote:
Porting does look good. Wouldn't open the skirt out too much, as it won't do anything much without the piston opened out too and this will make it rattle more. not worth the risk in my opinion.

Might get away with an extra spacer on that gear cog but the circlip is not meant to fill that gap. It's just a stronger clip. You'll be able to re-sell it or something.
hibbert wrote:
I don't know a thing about the gears but dood the porting looks great!
Thanks hibbert and Jack!

so its as good as it gets with that piston/cylinder wall overlapping the case ports a few mm I guess. If its not worth the improvement. I'll stick with the cylinder gasket face port profiling and leave the skirts alone.

My new found precise measurement tool in photoshop with translating the pixel to mm dimension is being put to good use. I've mapped out the exhaust port arc widening and raising the opening to the desired 42mm width and 2.35mm up for correct 125 transfer time. Here is the shape I think I need to hit with my grinding. Any opinions if this is a good target or should I try to open more up with straighter vertical lines on the sides of the exhaust port instead of a more trapezoid shape?

I'll print and cut this shape out to lay over the cylinder to mark out an outline for grinding to.

mal166ports_02_portingtemplate.jpg
new exhaust profiling target shape.

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Mon Oct 28, 2019 10:23 am quote
done with progress for the day on this, until I get some feedback on exhaust profiling. Don't want to start that without some confirmation I'm heading in the right direction. I believe I read in Jennings book that trap shape is a nice compromise between power and ring safety. FMP also seems to shape his exhausts as a trapezoid.


I profiled the cylinder transfer ports along the gasket face as well as o tuned the carb box and reed plate. Removed the cross bar on the LML reed plate as I use boyesen reeds which have their own crossbar built into the multistage reed.

also sanded 1000 grit on all the porting and about to grab some more metal polish to clean everything up nice!

So really all that is left now on the rebuild to get the engine finished is:

1.) exhaust grinding
2.) cylinder boring/honing
3.) rebuild primary drive with new springs
4.) not necessary but since I have everything apart, I am gonna get the cases vapor blasted.

and to finish the whole scoot there are a few other things I would like to get done before putting engine back in:

1.) replace fuel tap with sip fast flow with resevoir light.
2.) replace fuel line with crush proof line
3.) replace all control cables
4.) feed resevoir light wiring as well as cht and egt sensor wiring through frame
5.) tap a hole in neck into the glove box for gauges and resevoir light.
6.) on top of glovebox install westach dual cht/egt gauge and an old p200 headset control light for fuel resevoir gauge from fast flow tap.
7.) replace rear shock with sip performance shock (might have sourced the matching front shock from someone on here!).

IMG_20191028_124913.jpg
overview of cylinder gasket face profiling

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left side matches gasket now as best as possible without grinding the skirts to match.

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same for the right.

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view of the left without gasket.

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same for the right

IMG_20191028_130952.jpg
removed the crossbar on the stock LML reed plate. not needed and hinders airflow.

IMG_20191028_130959.jpg
cleaning up the old point of contact for cross bar.

IMG_20191028_131941.jpg
outline of overlap needing removal from the reed plate to match carb box

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and the same for the carb box to match the reed plate

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finished matching both box and reed plate to each other.

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another view of the smooth transition

IMG_20191028_134852.jpg
and the new carb box base profile

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new reed plate top profile

IMG_20191028_161141.jpg
smoothed out a sharp edge from casting. 600 grit and some metal polish.

IMG_20191028_161153.jpg
600 grit by hand and metal polish

IMG_20191028_161208.jpg
600 grit by hand and metal polish

Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Mon Oct 28, 2019 11:49 pm quote
The cylinder dosen't seem to line up with the gasket so well. Is that not finished?

Exhaust port shape is generally good but should be flatter at the top and a little rounder at the bottom. The rings cross the port at both ends. Trapezoidal shape is a good compromise for something that is to be a bit quicker than the average tourer.

Otherwise all going fine.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Tue Oct 29, 2019 5:28 am quote
Jack221 wrote:
The cylinder dosen't seem to line up with the gasket so well. Is that not finished?

Exhaust port shape is generally good but should be flatter at the top and a little rounder at the bottom. The rings cross the port at both ends. Trapezoidal shape is a good compromise for something that is to be a bit quicker than the average tourer.

Otherwise all going fine.
It is finished. It doesn't line up because the cylinder skirt blocks the case/gasket width at that spot and you suggested that widening the skirt and piston to match would not be beneficial enough to invite more rattle. If I were to properly match the cylinder to the gasket at that spot on both sides, I would need to cut the skirt wider. I guess I can try to blend in that corner just on the face enough to create a guide for airflow to get into the port, without cutting the skirt to match. But the skirt will still be blocking airflow except at the point where airflow enters the transfer ports on the gasket face along that edge on both sides.

Here is an updated exhaust port profile that I will try to match with grinding.

mal166ports_02_portingtemplate.jpg
flatter top and rounder bottom. both sides should have about the same curvature from side wall to horizontal.

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Tue Oct 29, 2019 4:29 pm quote
Further searching on SIP for short 4th gear appropriate for my stella EFL gearbox finally came up with a Piaggio original T5 4th that I believe is compatible. Much cheaper than the DRT, but probably not as hardened.

https://sip-scootershop.com/en/products/gear+cog+36+teeth+4th+gear+_22322900

But, as Jack suggested at some point, probably don't need a short 4th on this engine once it is rebuilt.

The P200 project which I am targeting more torque might get some use out of the short 4th DRT gear since it is meant for that gearbox.
Addicted
Joined: 26 Jan 2019
Posts: 689
Location: california
Tue Oct 29, 2019 9:45 pm quote
Swiss - just caught up.
Can see your grinding skills are getting pretty mad.
Case matching looks great.
Will have to go watch That Scooter Thing's how to - just for interest.
Think what Jack was referencing was the bottom edge of the exhaust port - currently flat.
Your rings are going to cross that plane - just like the top - so curved is better.
Bad sketch using thumb on phone below.

Also - You have some pretty thin margins between studs and cylinder holes - as well as at some points around perimeter of the base gasket.

I got some good advice from GT6 in that area - to use "three bond" on the gasket - and he is building some kind of aluminum blimps down under.
Stuff works.

I didn't import any of that brand - but quick search on line showed that its the same as "Honda Bond", or Yama bond or Suzuki what ever. I know SoCal uses Moto Seal. They are all intended for just this purpose. It is great insurance against unexpected air leak... Recommend.

mal166ports_02_portingtemplate_19939.jpg
See ugly blue line on your nice il. file.

Hooked
1984 PX(177)EFL
Joined: 14 Apr 2017
Posts: 201
Location: Cornwall UK
Wed Oct 30, 2019 1:04 am quote
Hi swiss; I thought better to reply to your pm here, so others can chip in. You might have covered it overnight anyway, but it would be rude of me not to reply:

I can see that the description of the DRT gear 40432910 says “px old/px lusso” and that the table (Sip p494) also lists 40432910 as the correct part number for short 4th gear (36) under the px old and px lusso column.

You say your gear came with a spacer, which you think may be to make the gear compatible with both; that does appear to be what DRT are intending, but I assume you've seen Sip p493, which shows the difference between the centre section of old px as 4.85mm, and that of px lusso as 6.43mm; a difference of 1.58mm (not the 1.3mm in your link, though your thorough measurements above might supersede that). So it isn't just the overall dimension of the stack of loose gears, it's the actual location of that 6.43mm centre section, where the crux lands (as dictated by the correct selector box), which I wouldn't be happy to have compensated for with a spacer, even if that's what DRT intend.

Given the choice of €100 for DRT 40432910 that might be OK, and €50 for Piaggio 22322900 that I know is correct, I'd be going for the latter. I understand you already have the 40432910 gear, which is listed as compatible with lusso(EFL) and getting parts from Germany to USA is a drag, but without Sip/DRT confirmation I wouldn't be hoping I'd understood; I'd be making sure.

I have no experience with DRT gears; far too expensive for my budget, or with anything specific to LML gearboxes if they're different at all; they're all EFL, right? I've covered what I know about the difference and compatibility of old px/lusso(EFL) in reply to your pm last night and here this morning, so you've got all I know on it. I'll post some links and images of the tables I'm referring to at the bottom; it might encourage others to share their knowledge, but I think you've moved on from this now anyway.

You could try Sip/DRT technical for clarification.
You could try Sip forum for advice/experience of others.
You could use an online translator and type in some of the Italian instructions.

https://sip-scootershop.com/en/products/gear+cog+36+teeth+4th+gear+_40432910

https://sip-scootershop.com/en/products/gear+cog+36+teeth+4th+gear+_22322900

https://www.sip-scootershop.com/files/catalogue/index.html#/493

https://www.sip-scootershop.com/files/catalogue/index.html#/495

Image1.jpg

Image2.jpg

Image3.jpg

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 3:04 am quote
Thanks sime for responding here. Your info is helpful and you see correct that I did read through those pages from sip catalog on gearing differences. You are also correct in that I've moved on. I am not planning on using that gear on my efl gearbox but am on my old p200 gearbox.

But, since the sip descriptor said they were compatible, I could not let it go without understanding how. My suggestion that a 1.3mm spacer might be the way to do it came from my actual measurements as that is the total difference between drt gear with included drt circlip from the LML gear with LML included spacer and circlip. My understanding is that if those total thicknesses are the same then they sit it the same exact spot in the gearing stack.

This was just an exercise to try to wrap my head around the concept of how this gearing works, old vs new. And yes, if I try a short fourth on the efl gearbox, the cheaper piaggio short fourth is the way to go in my opinion as well!
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 3:33 am quote
charlieman22 wrote:
Think what Jack was referencing was the bottom edge of the exhaust port - currently flat.
Your rings are going to cross that plane - just like the top - so curved is better.

Also - You have some pretty thin margins between studs and cylinder holes - as well as at some points around perimeter of the base gasket.

I got some good advice from GT6 in that area - to use "three bond" on the gasket - and he is building some kind of aluminum blimps down under.
Stuff works..
Hey charlieman22, thanks! Grinding isn't too bad if you take it slow and deliberate. Also reinforce your Dremel hand with your other hand to create a tripod of sorts. This works great when the tool is being used on the flat surfaces of the cases and the spin direction of the Dremel head is going against the direction of cutting movement of your hand. The Dremel head spin direction acts against your hand movement to help steady it. Where I noticed this breaks down and becomes more difficult requiring greater care and finer touch of both your Dremel pressure and off hand stabilization is when you are cutting inside the cylinder transfer ports along the gasket face. This is because the surface is not flat but like you are cutting into the sharp edge of a knife, and especially on tight angles requiring you to cut with the spin of the head. That creates a similar reaction to kick back on a table saw and pressing harder with your off hand to stabilize makes it worse. That's where I did get one slight gasket face scratch on the cylinder from kickback as the tool jumped out. I learned very quickly the safest way to approach that was soft shallow cuts while trying to be deliberate in your movement direction. What makes it worse is you are at risk of contacting the bore surface if things kick back.

Back to your suggestions... I have been wondering the proper gasket sealant to use on the base gasket and cylinder head to prevent air leaks. Whether it was grease, or something like the red permatex gasket sealant I have. Thanks for that tip, I'll try to find some of that other stuff to use. Terrified of getting another air leak which would lead to more wasted money. I've wasted enough at this point!

As far as the exhaust profiling, I did not even consider the bottom edge of the port as being too flat when Jack was mentioning that. My thought was that bottom edge should stay the way it was from factory as I thought changing that might alter the port timings somehow. If that's what he meant then yes I'll definitely round that bottom edge slightly and bring some of that curvature back into both top and bottom edges on my template you altered. I know that the top edge of exhaust defines the port duration, but have not thought about how the bottom edge or total height of exhaust opening relates to port duration, etc. Now you got me wondering about that!
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Joined: 26 Jan 2019
Posts: 689
Location: california
Wed Oct 30, 2019 7:37 am quote
Swiss,
In simple terms, the bottom fo the port doesn't effect timing.
If you look at the other recent threads - like my BLUE Bajaj fitting 60mm Crankshaft (Page 3) you will see how people judge where to lower the exhaust port to.
Just install the base gasket and cyl - put piston at bottom of stroke - and use a sharpie or other means to mark top of piston. Safe to take the ex. port to that level as I understand it. Use this extra distance for free enlargement without altering timing - and better shape.

Reader's digest version of what Jack has elsewhere advised:
You have a fairly aggressive width on the ex. port. By keeping some curvature top and bottom, you take some strain off the rings as they pass these two planes above and below.
Keeping the very center 25 mm or so of the opening (visual estimate on my part) flat seams to be ok when trying to reach maximize ex. outlet opening - though a nice arc is a slightly safer play on your rings with not much compromise on opening. Jack can confirm this.
Quote:
I have been wondering the proper gasket sealant to use on the base gasket and cylinder head to prevent air leaks. Whether it was grease, or something like the red permatex gasket sealant I have.
Strongly recommend Moto Seal or Honda Bond type - not red permatex -for base. You won't be sorry.
Editor's note:I used this on my cyl upgrade after the tip I mentioned from GT6 and second thumbs up from SoCal. I had the chance to see how it held up when I took the bike apart after about 800+ miles. I way overdid it - it was ugly - and some squished in to my transfer ports - whose surfaces were polished and not prepped for bonding with any cleaner prior to assembly of my motor. I was kinda astounded - the Honda Bond was fixed and unaffected by use. Had to scrape it off even though it has been subject to heat gas and oil. It is the real deal.
Addicted
Joined: 26 Jan 2019
Posts: 689
Location: california
Wed Oct 30, 2019 7:40 am quote
Swiss,
On 4th gear question.
If you want to avoid shipping fees - you might find that you can order through Scooter Mercato. I believe he makes a weekly order - so the overseas shipping is likely not a factor. Perhaps at least worth checking if you are going to order a new gear and want to avoid shipping fees = to the gear cost.
-CM
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 4:00 pm quote
charlieman22 wrote:
Swiss,
On 4th gear question.
If you want to avoid shipping fees - you might find that you can order through Scooter Mercato. I believe he makes a weekly order - so the overseas shipping is likely not a factor. Perhaps at least worth checking if you are going to order a new gear and want to avoid shipping fees = to the gear cost.
-CM
Ahh just went through that page on your thread and it all makes sense. Missed that whole discussion as it was during my sabbatical from this site over the last few months. Been glancing at The recent posts on that thread since checking in again and have been lost cause topics were beyond technical stuff I've not had brain power to start thinking about yet, until I get to it on my build. To be honest, some of the other build threads have my eyes glossing over lately from technical stuff I haven't considered yet. I'm sure it will all make more sense once I start tackling those topics and see it in physical form. Wish I had checked the bottom level of piston before I just removed the bearing to grind. Makes mounting the crank and piston more work than I want to right now. Luckily I did measure the stroke accurately and know the pbt at tdc. So I can just measure down from pbt with caliper and place the rings in cylinder to get the top line of piston at bdc without mounting crank and piston.


I'm definitely going to try that sealant you suggest. I plan on using scooter Mercato for sip orders when small items needed but prefer to do large orders myself. Still haven't decided if I want to do short 4th on this yet. Jack says don't bother. But I have some hills in my neighborhood, and windy trip over the Verrazano bridge which is a relatively steep incline traveling at that speed on the shift point between 3rd-4th for commute which make me wonder if I will regret not installing it once I'm commuting regularly.
Ossessionato
1980 P200E, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 3990
Location: San Diego, CA
Wed Oct 30, 2019 5:10 pm quote
Do the short 4th, you will not regret it. It just makes the 3-4 gap right instead of huge. I always use Scooter Mercato or Scooter-speed for SIP orders, no customs to deal with and they will make things right if something goes wrong. And finally yes, Motoseal is amazing.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 6:38 pm quote
Got home from work late tonight and just couldn't leave the scooter alone after thinking about multiple of these questions all day at work.

1.) plenty of space to round out the bottom of the exhaust port. I don't think I see the need for grinding it all the way down, not sure how that would benefit, but I do see the benefit in smooth transitions to prevent ring snags. Photos below of rings in cylinder at the height of piston when @ BDC. I also realized as I was placing the ring in bore for this physical check, that I didn't even need to do it in the real world. I can use the port tracing I already did and mark out the piston top @ BDC in photoshop on the document I'm already using to plan the exhaust port profile.

2.) old vs EFL gearing still bugging me why the DRT old wouldn't be compatible if just the 4th gear is mixed with stock EFL gears. Even though I know people said it isn't compatible, I needed to understand it visually for myself, to truly understand the concepts. I spent an hour trying every iteration of assembling both my EFL (LML) drive gears and my P200 "old" gears stock and with DRT short 4th on both. Took pictures. I think I now understand that this most likely wouldn't work as everyone has suggested. not because the gear doesn't fit and mesh well with the primary drive, but because of the difference in depth the shift cross has to travel to enter into 4th gear vs every other gear.

LML 4th gear has an approximate 1.72mm gap between the outer edge of the gear where each gear slides up against each other, and the closest edge of the inner tooth to 3rd gear. The P200 stock 4th has approximately a 2.69mm gap. The DRT short 4th has a 2.58mm gap. I think what this means is that all gears on the EFL drive shaft have approximately a 1.72mm gap from outer edge to inner tooth.. not counting the other side of the previous gear's spacing (which should be consistent for all gears in the stack). And for the "old" gear stack, all gears have approximately a 2.6+/-mm spacing between outer edge of the gear to inner tooth. So the selector box when the stacks are correctly populated with the appropriate gearing for the drive shaft have a consistent distance to move the cruciform to shift into each gear. Using the DRT short 4th on the new EFL drive shaft within all other gears that are stock EFL gears means that the distance from 3rd to shift into 4th will be 0.86mm further than what it should be for that selector box. In my limited knowledge I do not think that it is possible to shim the selector box in such a way that will alter the cruciform travel distance for only 1 gear to adjust for that different gap. This is why those gears do not work in an EFL gearbox as a loose gear among stock gears. Photos below of all my iterations and measurements.

As an aside, I noticed the DRT short 4th is a thicker gear overall than both the EFL and "old" gears. this is why the gap between 4th and 3rd when looking at the drive shaft put together is narrower than the rest of the gears, which may or may not be unrelated to the differing distances I am talking about in relation to edge to tooth gap on each gear.

3.)
sdjohn wrote:
Do the short 4th, you will not regret it. It just makes the 3-4 gap right instead of huge. I always use Scooter Mercato or Scooter-speed for SIP orders, no customs to deal with and they will make things right if something goes wrong. And finally yes, Motoseal is amazing.
One vote for short 4th, one vote against. I am leaning towards doing it because I don't want to split cases again after just doing this rebuild. I'm not terribly concerned about a ~3mph loss in top speed, especially given that Jack has guided me towards a very fast timing and I will have excess speed in 4th for whatever commuting/driving I plan on doing. Are there any cons to doing a short 4th? I must also mention that I've already upgeared my gearbox slightly over stock by going from 21 tooth clutch to 22 tooth. 22/68 now over the stock 21/68. I think maybe this is why short fourth might not be necessary.

IMG_20191030_205102.jpg
plenty of space to round out the bottom of exhaust.

IMG_20191030_205112.jpg

IMG_20191030_211542.jpg
LML "EFL" drive shaft with short 4th from DRT.

IMG_20191030_211618.jpg
LML driveshaft w/DRT short 4th with LML primary

IMG_20191030_212058.jpg
LML drive shaft with stock gears.

IMG_20191030_212123.jpg
LML drive shaft w/ stock gears and LML primary

IMG_20191030_213206.jpg
P200E "old" drive shaft with stock gears

IMG_20191030_213238.jpg
"old" drive shaft w/ stock gears and "old" primary

IMG_20191030_213424.jpg
"old" drive shaft with DRT short 4th.

IMG_20191030_213506.jpg
"old" drive shaft w/ DRT short 4th and "old" primary

IMG_20191030_214622.jpg
LML 4th gear measurement of that gap from gear edge to closest inner tooth edge.

IMG_20191030_214715.jpg
"old" 4th gear measurement of that gap from gear edge to closest inner tooth edge.

IMG_20191030_214550.jpg
DRT short 4th gear measurement of that gap from gear edge to closest inner tooth edge.

Ossessionato
1980 P200E, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 3990
Location: San Diego, CA
Wed Oct 30, 2019 6:46 pm quote
Yes, the “top speed loss” is irrelevant compared to the hill improvement if you have a lot of hills. Since 55 is the top speed limit on the roads I use, the top speed means nothing to me.
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 7:43 pm quote
edit: updated exhaust profile below.. after most recent comments from Jack below.

Last edited by swiss1939 on Wed Oct 30, 2019 7:56 pm; edited 3 times in total
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Wed Oct 30, 2019 7:44 pm quote
Lot of grinding to do. The blue line that CM drew is what I meant. The bottom of the exhaust should be flush with the piston at BDC or slightly under. Leaving the port smaller does go but the mid range will lose some torque if there is a lip.

With the extra width, height and BDC, that port is going to look pretty big when you are done. Watch for the stud holes and be sure to open up the whole port and not just the edge.

If you were pulling the LML 4th gear ok before, it will be pull even better after this rebuild. No issue with going for a short 4th but if not needed will just end up using more fuel on the commute. Will rev plenty high enough to go fast with lower gearing, maybe even faster. If there are issues the 21 clutch cog could go back in. Plenty of options.

Last edited by Jack221 on Wed Oct 30, 2019 8:06 pm; edited 1 time in total
Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 7:54 pm quote
Jack221 wrote:
Lot of grinding to do. The blue line that CM drew is what I meant. The bottom of the exhaust should be flush with the piston at BDC or slightly under. Leaving the port smaller does go but the mid range will lose some torque if there is a lip.

With the extra width, height and BDC, that port is going to look pretty big when you are done. Watch for the stud holes and be sure to open up the whole port and not just the edge.

If you were pulling the LML 4th gear ok before, it will be pull even better after this rebuild. No issue with going for a short 4th but if not needed will just end up using more fuel on the commute. Will rev plenty high enough to go fast with lower gearing, maybe even faster. If there are issues the 21 clutch cog could go back in. Plenty of options.
Ok that is great info.. lower exhaust port = more torque mid range. I like that answer. I also like the answer of better fuel economy with regular 4th gear!

updated exhaust profile after most recent feedback about lowering port opening in addition to raising opening. Now there really is a lot of grinding to do. I think I may be a little more cautious about lowering it and leave a bit more gap than in this included image... until I rebore it and get the correct piston installed to make sure exactly where that line is I can get close to.

I'll have to take a closer look at where the studs are in relation to my grinding to make sure I don't f' this one up again!

mal166ports_02_portingtemplate.jpg

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 8:01 pm quote
Jack221 wrote:
The bottom of the exhaust should be flush with the piston at BDC or slightly under.
I think you are saying it is ok to go this far? as long as its not too aggressively lower than piston. I will turn it to 11 once I get the new piston and crank on after re-bore. Then it will be accurate... and "louder"!

mal166ports_02_portingtemplate_exhaust_lowerlimit.jpg
safe to go slightly below piston top?



Last edited by swiss1939 on Wed Oct 30, 2019 8:10 pm; edited 1 time in total
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1557
Location: London UK
Wed Oct 30, 2019 8:08 pm quote
The bottom can be a little flatter. Yours should be less wobbly. Ok to go slightly too far.

mal166ports_02_portingtemplate_71000.jpg

Molto Verboso
1980 P200E project, 2005 Stella Mal 177 MKIII in pieces
Joined: 20 Jul 2018
Posts: 1128
Location: Staten Island, NY
Wed Oct 30, 2019 8:13 pm quote
ok! I'll transfer that flat section onto my digital template to print out and cut out as a paper template for grinding. Might hold off until Monday/tuesday or next sat/sunday when I have two days off in a row and a few days to build up courage to remove that much material from this cylinder!
Addicted
Joined: 26 Jan 2019
Posts: 689
Location: california
Wed Oct 30, 2019 8:14 pm quote
Swiss,
Here is an article that may be helpful: https://scooterlab.uk/vespa-px-gear-selector-boxes-part-1-workshop/

At issue is not the xmas tree and drive shaft gears alignment.
Its where the selector box places the shift cross.
A few millimeters apparently makes a big difference.

Thats why Sime noted that simply shimming the total drive shaft stack to take out slack - would get rid of play - but not necessarily align that gear with the cross.

For what its worth - which is very little - I like the short 4th. won't matter what gear your in - you will have get up and go in your right hand. To Jack's point - if you undershoot and really want lower RPM, you can always just alter the clutch primary = don't have to split to adjust.
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