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@blake7even avatar
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I'm going to keep my progress posted here. I welcome any advice or suggestions as I real am at the beginning of this.

So I bought this, a 68 Sprint 150.
External inline image provided by member with no explanatory text
External inline image provided by member with no explanatory text

It's my daily hack and it lives outside....& it's sloooooww 2 port. The front end dives hard and the front brake is not confidence inspiring. But I think it looks pretty cool so I'm building a 'Sleeper'

Starting with this. An LML/Stella reed valve motor in need of seals. The top end, crank and a bunch of other stuff are already in the bin.

External inline image provided by member with no explanatory text

So first thing first. The Malossi 166 Kit. It will be mated up to a Worb5 or BGM 60mm crank with port timing around 120Tr / 172Ex or so...... i think.

Day 1.

Start sorting the piston out!

External inline image provided by member with no explanatory text
External inline image provided by member with no explanatory text

Ports roughed out.
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⚠️ Last edited by blake7even on UTC; edited 2 times
@bholinath avatar
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Rally 200, SS 180, ET3
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Try the 33% stiffer spring on the front end. It solved my problem of the forks bottoming out on my rally. And still looks stock.
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bholinath wrote:
Try the 33% stiffer spring on the front end. It solved my problem of the forks bottoming out on my rally. And still looks stock.
Might do this as an interim solution. Planning on using the SIP PKXL style fork the do for disc conversion but use a PK drum instead.

Should look to stock to all but those in the know I hope.
@ginch avatar
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Those drums are meant to be very good. Nice Sprint. What pipe are you going to use on it?
On the LML cases the transfers are a bit longer than you'll find on the cylinder so there's a little bit of work to do there to match it up.
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Ginch wrote:
Those drums are meant to be very good. Nice Sprint. What pipe are you going to use on it?
On the LML cases the transfers are a bit longer than you'll find on the cylinder so there's a little bit of work to do there to match it up.
Looking at the cases the transfers look bigger than a PX but not as big as the '5 port' I've seen pictures of. I know in the UK some of the 125 motors supplied came with strange mixes.
I'll have to take out some in the case and a little off the barrel to match it up.
Exhaust is a BGM big box I have here in the wrapper. Keep the sleeper look but works well.

BGM say I can use any port timing but I've asked for a recommendation.
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blake7even wrote:
BGM say I can use any port timing but I've asked for a recommendation.
That would be interesting to find out... that is something missing from all the dynos you see. I know they seem to be getting some pretty high numbers from the big box but there would have to be timings that work better than others. Let's know how you get on.
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Ginch wrote:
blake7even wrote:
BGM say I can use any port timing but I've asked for a recommendation.
That would be interesting to find out... that is something missing from all the dynos you see. I know they seem to be getting some pretty high numbers from the big box but there would have to be timings that work better than others. Let's know how you get on.
Got an email from Uwe at Scooter Center. Read Below.

"I've tested both variants on a nearly stock 166cc cylinder and a scorpion exhaust which' characteristic is pretty similar to the bgm bigbox when used on the 166 Malossi kit.

1.5mm head gasket (red graph)

1.5mm base gasket (blue graph)

Exhaust port is slightly widened and port height about 1mm altered to top. But also without modifying the exhaust port you'll get impressive results out of this kit in combination with the bgm exhaust.

I would suggest that you start with the 60mm crank on stock port timings to get an Impression if the engine characteristic will fit your purpose.

All changes to the exhaust port will increase the power output but will not change the characteristic in principle.

With a 1.5mm base gasket you will get (roughly) 124°/173° timings which is a good starting point.

The bigbox supports a wide power band, therefore the 124° transfer timing is not to much."
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@ginch avatar
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It's kind of what I expected from them - or SIP for that matter. Doesn't quite answer the question but sort of leaves you with more questions more often than not.

I have heard that the big box is good but to say that it's basically the same as a proper expansion chamber seems pretty odd.

So in the end he says try it as is and see. Probably not such a bad idea.
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Ginch wrote:
It's kind of what I expected from them - or SIP for that matter. Doesn't quite answer the question but sort of leaves you with more questions more often than not.

I have heard that the big box is good but to say that it's basically the same as a proper expansion chamber seems pretty odd.

So in the end he says try it as is and see. Probably not such a bad idea.
Got more from them. Very impressive on the M1x. I'm going to raise the exhaust 1mm, widen it a touch. 1.5mm base gasket and go from there. I'll post the exact timings and findings.

Quote from Scooter Center.

"Here's another diagram of a customer from us with a 166cc kit with 60mm stroke, but with reed valve, 30mm PHBH Dell'Orto and 185°/125° timings.

Blue: PM Tuning Exhaust (old design)

Red: BigBox"

External inline image provided by member with no explanatory text

"yes the box can handle also the very powerful Quattrini M1X cylinders.

In this diagram you can see it perform on a fast road engine with a 62mm crankshaft, 38mm carb on a big reed intake and ported M1X Cylinder with 128°/192°.timings and a vespatronic iginition.
Green is a "real" performance exhaust from Nordspeed."
External inline image provided by member with no explanatory text
@ginch avatar
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That does look impressive. Glad they were able to provide you with something to go on. I'll be looking forward to hearing how it turns out.

Before you buy a crank, have a read of this. Fascinating and exciting stuff although I have to admit to needing to read through several times to start to understand some of the finer points. http://www.scootercentral.net/forums/viewtopic.php?f=15&t=15818
In light of this, it could be very beneficial to use this crank - http://www.sip-scootershop.com/en/products/bellshaped+crankshaft+mazzu_45041000 It's made of the same good steel as their full circle cranks and more than a cut above the run of the mill Mazz stuff. Also it's better balanced, allows more case volume, and it's out of the way more often for better gas flow. And a similar price to the BGM. I'll be interested to see what you think after reading that thread.
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UTC quote
Ginch wrote:
That does look impressive. Glad they were able to provide you with something to go on. I'll be looking forward to hearing how it turns out.

Before you buy a crank, have a read of this. Fascinating and exciting stuff although I have to admit to needing to read through several times to start to understand some of the finer points. http://www.scootercentral.net/forums/viewtopic.php?f=15&t=15818
In light of this, it could be very beneficial to use this crank - http://www.sip-scootershop.com/en/products/bellshaped+crankshaft+mazzu_45041000 It's made of the same good steel as their full circle cranks and more than a cut above the run of the mill Mazz stuff. Also it's better balanced, allows more case volume, and it's out of the way more often for better gas flow. And a similar price to the BGM. I'll be interested to see what you think after reading that thread.
Wow. My head hurts.

Well from what I can gather I have a couple of things to think about.

The BGM crank is forged. Thats why I like it. It's also currently unavailiable so may as well be forged from unobtainium. It's also not perfect for reed induction. But it's forged.

Here's what I got from that thread, give or take.
105mm rod on 57mm stroke = Good.
105mm rod on 60mm stroke = Bad.
High case ratio = Low transfer port (short duration) = shit exhaust is ok.
Low case ratio = High transfer port (long duration) = Good exhaust is neccesary.

This what you got???

Now if I use the that Bell crank (110rod 60mm stroke) it will lower the case ratio (as there will be more volume) and the 110 rod will lengthen the duration... I think!?

I will also have to space the cylinder off by 6.5mm but the port timing should be a nats cock off what it would be with a 105 rod?

So thats all good as long as the BGM Big Box does the business. I think.....
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blake7even wrote:
Wow. My head hurts.
Check!
blake7even wrote:
Well from what I can gather I have a couple of things to think about.

The BGM crank is forged. Thats why I like it. It's also currently unavailiable so may as well be forged from unobtainium. It's also not perfect for reed induction. But it's forged.

Here's what I got from that thread, give or take.
105mm rod on 57mm stroke = Good.
105mm rod on 60mm stroke = Bad.
High case ratio = Low transfer port (short duration) = shit exhaust is ok.
Low case ratio = High transfer port (long duration) = Good exhaust is neccesary.

This what you got???
To be honest the high-low business didn't stick in my brain... and did they draw a corelation between case volume and duration?
blake7even wrote:
Now if I use the that Bell crank (110rod 60mm stroke) it will lower the case ratio (as there will be more volume) and the 110 rod will lengthen the duration... I think!?

I will also have to space the cylinder off by 6.5mm but the port timing should be a nats cock off what it would be with a 105 rod?

So thats all good as long as the BGM Big Box does the business. I think.....
I'm fairly sure that they were saying that the duration is more or less unaltered by the longer rod? Maybe I need to re-read.
I know the 6.5mm is close, but to be sure, use this - http://www.race-base.com/2t-tools/steuerzeit/


These are a couple of the points that I took from that thread. As well as Richard's big thumbs up for his setup towards the end. TA = time x area - the other factor in duration - sorry if you knew that.
allyourbasearebelongtonik wrote:
By increasing rod length you can get more transfer TA at lower duration. This would make more torque at mid-range and the motor would not be peaky.

During experimenting on a stock Stella cylinder, I found that increasing transfer duration made for a peaky motor with no guts at low rpm, and thus for a slower engine. By increasing rod length you gain more mid-range and less peaky motor, thus making it faster. In real world conditions, like Deals Gap, you really notice how slow a peaky motor is.
A peaky motor can be fun to ride but pretty soon you wish you had some extra gears.
allyourbasearebelongtonik wrote:
When a rod length is increased, all other things being equal, both transfer and exhaust Time Area increases, regardless of the fact that dwell at BDC is shortened with longer rod. ...but by increasing rod length you gain exhaust TA and this is something worth exploring.
Another benefit is that longer rods increase crankcase volume, which should be done in any case (on scooters) but especially when a larger cylinder is used (to restore favorable crankcase compression ratio).
And of course the bell crank also increases case volume (and are less prone to twisting due to matching lobes).

One thing that I had forgotten until just now was the gudgeon pin size. 15mm for the Malossi but 16mm for the crank. He got around that by using a different piston... you obviously don't want to do that as A. you just bought it and B. they're such a nice design. What about having a bush made for the rod? Ought to be fairly straightforward for someone with a lathe.
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The volume/duration thing was argued thus.

High case pressure (big volume crank, larger piston, small vespa case) forces Petrol in and the exhaust scavages little. too higher pressure the petrol mix flys unburnt into the exahaust.

Lower the case pressure and the exhaust does all the work so it had better be a good exhaust.

So the latter will work nicley with a longer duration as the exhaust is scavaging and the former will prefer a shorter duration so you dont throw fuel directing into the exhaust unburnt. I think.

I got the impression that a longer rod put less angular strain on the piston and altough the degrees of timing hadn't changed because of the dwell change the duration had. Could be wrong.

All in all I'm sold on the crank but the gudgeon pin cancels it for me. A sleave of 0.5mm thickness isn't somthing i want to be relying on.

So either I find out why nearly all longstrokes are fitted with 105mm rods if they are so bad
or I find a source for a 110mm longstroke for 15mm gudgeon pins.

Or I scrap it all and just go 57mm stroke.
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A 110mm rod moves the piston the same as any other rod of any other length. A 4,000ft long con-rod will move the piston the same as a 105mm con-rod.

The stroke isn't affected by the length of the rod.

A longer rod will result in a smoother running engine because it moves the piston further up the bore so that the torsion that occurs at the bottom doesn't happen or is lessened. The rod no longer shoves the piston into the wall of the cylinder after passing BDC.
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SFvsr wrote:
A 110mm rod moves the piston the same as any other rod of any other length. A 4,000ft long con-rod will move the piston the same as a 105mm con-rod.

The stroke isn't affected by the length of the rod.

A longer rod will result in a smoother running engine because it moves the piston further up the bore so that the torsion that occurs at the bottom doesn't happen or is lessened. The rod no longer shoves the piston into the wall of the cylinder after passing BDC.
/\ this.

What I don't understand is why only 200 cranks have the luxury of rod length choice.

Everything I can find for 125/150 has a 105mm rod.

I guess I'll have to live with it.
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Have a reputable shop build a custom crankshaft for you. SuperDuper Serious Outdoors can build you whatever you want. That shop is one of the best in the biz.
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SFvsr wrote:
Have a reputable shop build a custom crankshaft for you. SuperDuper Serious Outdoors can build you whatever you want. That shop is one of the best in the biz.
Agree. To be honest I have to reign myself in. I'm building a <20hp 166 motor & I was considering a 300-400 odd quid custom crank.

Naa.

I've ordered this.

External inline image provided by member with no explanatory text


Flowed (not bell) crank as the bell cranks are lots more money but I am sold on them. Seems to be lots of argument between flowed and Bell but they are all LPC cranks. If I were building a 25hp> 200 motor I'd go with the 100 pound more expencive bell crank.

Piston is done and i'm onto polishing the exhaust port but holding off raising it untill i can measure it all up together.

http://www.scooter-center.com/product/1620016/Crankshaft+RACING+reed+intake+60mm+stroke+lip+type+Vespa+PX125+PX150?meta=?cat=C_V_VNX2T&catmatch=CAT_KURBELWELLE_KURBELWELLE
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blake7even wrote:
To be honest I have to reign myself in. I'm building a <20hp 166 motor & I was considering a 300-400 odd quid custom crank.
So did you speak to someone and get a quote for a crank?
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Ginch wrote:
blake7even wrote:
To be honest I have to reign myself in. I'm building a <20hp 166 motor & I was considering a 300-400 odd quid custom crank.
So did you speak to someone and get a quote for a crank?
To clarify I didn't. I just saw all the >25PS cranks were £250+ an I wanted a new rod swapped into that.

Today I roughed out the ports, raised the exhaust and started to smooth it out. I also started roughing out the casings to match.

Anybody tells you the LML 5 port is a 'good' match for the Malossi isn't doing it right. The barrel needs the side ports widened 2-2.5mm on the exhaust side and the case needs raising the opposite side 3-4mm. The case also needs deepening across the middle if the transfer a mm here and there. It's actually harder than a '3 port' as you have to adjust the barrel. But you do get bigger transfers. I'll get some before/after pics as I've only adjusted one side of the case.

External inline image provided by member with no explanatory text
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Here you can see how much has to be removed from the malossi to match the '5 port' transfer shape.
Nearly done roughing out. Just waiting on some smaller burrs.

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I did say that... looks like you're doing a nice job though.

What intake/carb are you going to use?
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Ginch wrote:
I did say that... looks like you're doing a nice job though.

What intake/carb are you going to use?
I'm in two minds. I like the PKW copy [redacted] do and it's cheap but the only review I can find says without a pump you get fuel starvation when the tank is low. I'll be commuting on it as I am now to a low fuel condition is weekly.

I'm wondering if to go PHBH but not sure if the same will happen.

The other idea is to keep with the 'sleeper' theme and mod a 24/24 or 26/26 with the larger float needle and drill out the main float channel a bit. Fit it under a Pinasco 'air box' and see how that goes.

I might try that first as most of those parts are around me and if I'm not happy I can easily move up to a modern carb. Anybody want to chip in with suggestions ?

Sooooo.., the miss's went out ..,,
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Vader has 3 motors with that type of carb and doesn't run a pump, just a fast flow tap (steer clear of the sip tap).

I chose your latter route and stayed with the SI. When I do go that direction I'll get either the PWK-type Polini https://www.treatland.tv/polini-PWK-30mm-carburetor-p/polini-pwk-201.0169.htm or the BGM Pro PWK.

But I haven't heard terrible things about the [redacted] carb. And even Scooter and Service use their manifold in their kits.
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Ginch wrote:
Vader has 3 motors with that type of carb and doesn't run a pump, just a fast flow tap (steer clear of the sip tap).

I chose your latter route and stayed with the SI. When I do go that direction I'll get either the PWK-type Polini https://www.treatland.tv/polini-PWK-30mm-carburetor-p/polini-pwk-201.0169.htm or the BGM Pro PWK.

But I haven't heard terrible things about the [redacted] carb. And even Scooter and Service use their manifold in their kits.
Oh ok. Typically I have a fast SIP tap in my workshop (shed). I'll get a BGM one then. Thanks for the tip as S'RS have a LML reed specific manifold that would suit my cases lovely.

I'll probably run it in on an SI then when it's all dialled in ill fuck it up by changing the carb!
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blake7even wrote:
I'll probably run it in on an SI then when it's all dialled in ill fuck it up by changing the carb!
And the whole process starts again when you seize it! I think they call it the circle of life or something.
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Ginch wrote:
blake7even wrote:
I'll probably run it in on an SI then when it's all dialled in ill fuck it up by changing the carb!
And the whole process starts again when you seize it! I think they call it the circle of life or something.
So true! I'm a week of dremel work into the kit and I've started muttering at it 'you'd better not nip up you little shit!'
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I'm not sure what carb I want to use so for now to keep things moving I'm going to use the 24/24 SI.

I decided to blend the reed valve housing into the carb housing and remove the reed housing centre bar.

I also took it out some so now its 900Sq mm instead of 709Sq mm.
Basically what this guy did but more so, though he mensions he got further than the pics he posted.
http://www.lmlocgb.co.uk/phpBB3/viewtopic.php?f=6&t=7598&start=20
External inline image provided by member with no explanatory text
External inline image provided by member with no explanatory text

Standard cage

External inline image provided by member with no explanatory text

External inline image provided by member with no explanatory text

Modified cage/carb box/carb assy.
@ginch avatar
UTC

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
 
Veni, Vidi, Posti
@ginch avatar
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
UTC quote
Nice work!

I saw that by HandsomeJack on Stella Speed, I think he was pretty happy with the results.
A mate of mine runs an LML case w/Polini 177 and he swapped the original stainless reed for a Polini-branded fibre type reed. The opening edge became ragged in a pretty short time, within a thousand k's from memory. He went through a few and changed back to the stainless one.
I haven't heard anyone else mention this sort of problem, but Rob Hodge did say in another thread that there is a lot of stress on the reeed itself compared to say an rd350-style which is at 45 degrees to the flow. I think HandsomeJack was running Boysen reeds.
Not something to lose sleep over but perhaps something to keep an eye on with a higher performance motor.
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
Ginch wrote:
Nice work!

I saw that by HandsomeJack on Stella Speed, I think he was pretty happy with the results.
A mate of mine runs an LML case w/Polini 177 and he swapped the original stainless reed for a Polini-branded fibre type reed. The opening edge became ragged in a pretty short time, within a thousand k's from memory. He went through a few and changed back to the stainless one.
I haven't heard anyone else mention this sort of problem, but Rob Hodge did say in another thread that there is a lot of stress on the reeed itself compared to say an rd350-style which is at 45 degrees to the flow. I think HandsomeJack was running Boysen reeds.
Not something to lose sleep over but perhaps something to keep an eye on with a higher performance motor.
Thanks, It's coming together slowley. still wiating on my crank for a dry build.

As for the reeds i'll suck it and see. you can not use the original reed effectivly as it has a split in it to that seals over the bridge. that bridge is now in the bin.
I could use some stainless spring steel foil. Stock is 0.20mm so i could use 0.15mm but my issue with the stainless is they last forever then suddenly snap and take out at least your bottom end.

The carbon wears but as long as it's not <1k!!! i'm cool with swapping it at oil changes.

I'll check at my dry build but as long as the end doesn't touch the crank it should be ok. for extra points i may 'seal' the edges with epoxy.

Looking at the LML reed block there is room for design improvement to angle the reed more into the case. I may look at that another day but it would mean removing the cobonded rubber seal.

here's a Speedfight reed block that looks more angled, uses a carbon reed and almost looks like it will bolt on!


External inline image provided by member with no explanatory text
@ginch avatar
UTC

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
 
Veni, Vidi, Posti
@ginch avatar
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
UTC quote
That does look good. Worthwhile getting a gasket to compare the holes.
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
So i had the living room to myself this morning and now it is covered in metal filings!

I got my crank and 1.5mm base gasket through and the transfer cutout was different again! So I had to enlarge the top side of the transfer on the barrel after already enlarging the exhaust side. The transfers are much, much bigger than i was planning.

No need for welding though.

I smoothed and flowed the reed area and have matched up one side. I'll match up the other another day.

1 port enlarged... again and the transfer split 'knife edged'

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Reed area flowed
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View of enlarged ports and flowed case area.
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External inline image provided by member with no explanatory text
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
Finished the porting work. I'll just go over it with a flap wheel but the shape is there now. The transfers are nothing like the old vespa originals now. And the reed valve area has been smoothed and blended.

I've got a couple of jobs I can do next like fill the autolube channels in the reed block and carb box but then I need to wait until I'm paid to get my paws on the BGM clutch and uprated cush springs.

I'm keeping the 21/68 gearing and as it's LML/Stella its a Late 150 gearbox same as P200.
So it's up geared anyway and I will using it to surprise the streets of London. It's not a tourer.

I need to order an SIP speedo at the same time so I can wire it in at the same time as the 12V conversion. I'm going to fit the CHT wires and so I'll get revs and speed and CHT while looking nice and stock.

External inline image provided by member with no explanatory text
External inline image provided by member with no explanatory text

you can see from the reed inlet all the way to the transfer here.
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@socalguy avatar
UTC

bodgemaster
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7070
Location: So Cal
 
bodgemaster
@socalguy avatar
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7070
Location: So Cal
UTC quote
Loving this thread.

To keep it sleeper ... which we dig ... you might want to put an original kick start on there. No giveaways until the light changes, heh heh.
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
SoCalGuy wrote:
Loving this thread.

To keep it sleeper ... which we dig ... you might want to put an original kick start on there. No giveaways until the light changes, heh heh.
Definitely putting a 'classic' style kickstart for the PX motor on there. I thinking I'm chucking a grey tubeless wide rim on the back.

I like the look of the 'pro street' sleepers in America. They fit massive rubber to deal with the HP but they cut the inner arches in so the wheels stay inside the car.

External inline image provided by member with no explanatory text

I like the idea of a wide tyre in there but on a grey rim so it looks stock. I know I'm never going to fool a fellow scooterist but I want your average man to be stunned by this 60's hair dryer!
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
So I've finished with the dremel now and it's all matched up.
Just waiting on funds now to go on. Pressing parts are a genuine cruciform and genuine cylinder studs from Piaggio. The gears are shimmed up and I've taken the Cush gear apart to load in tougher springs.

Today's job, well, big tyre kit now as there's no going back!
External inline image provided by member with no explanatory text
External inline image provided by member with no explanatory text

Bearings all out now too.

External inline image provided by member with no explanatory text
@socalguy avatar
UTC

bodgemaster
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7070
Location: So Cal
 
bodgemaster
@socalguy avatar
63 GL, 76 Super (x2), 74 Primavera (x2), 79 P200, 06 Fly 150
Joined: UTC
Posts: 7070
Location: So Cal
UTC quote
Holy crap, you are serious. Keep it up man. This is good stuff.
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
Not mega progress as I'm waiting for the postie to bring me some metalic goodies.

Installed bearings.

Recipe:

No preheat required run your oven to 200C or Gas mark 7.
leave for 20 mins with the Bearings marinating overnight in the freezer.
Point bearing roughly in the direction of the seat and it'll fall in.
Leave hammer in the toolbox and rest.



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External inline image provided by member with no explanatory text

External inline image provided by member with no explanatory text

Cleaned up some asjuster threads.


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Nice tip, deburr the clutch arm so the cable doesn't snag and fray on burrs.
External inline image provided by member with no explanatory text
@ginch avatar
UTC

Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
 
Veni, Vidi, Posti
@ginch avatar
74 Super, 75 Super, PX project, LML off-roader and '66 Blue Badge Smallframe
Joined: UTC
Posts: 8595
Location: Victoria, Australia
UTC quote
Sure is looking good. What's the go with the clutch arm? What seats in the hollow you've made?
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
Ginch wrote:
Sure is looking good. What's the go with the clutch arm? What seats in the hollow you've made?
Thats more or less the shape it was, I just removed the casting burrs and marks so it's smooth. The idea is the cable has nothing to rub on or catch on during it's throw. Might work, might be bullshit but it took 25 seconds and it can't hurt.

Can't remember where I read it.


New 'toys' in the Post;

Vepspatronic
SIP Cosa 2 clutch
22t clutch gear
Genuine Piaggio barrel studs
P200 cush springs
BGM shock
COSA clutch nut
Genuine Piaggio cruciform
Hotrod AL stabaliser
Clauss studio bushes

That lot should get the cases back together, still need a Carbon Reed and a 5.2mm float bowl top to build onto my 24/24 that has been drilled out for flow.

oh... and the tubless wide rim & tyre.
OP
@blake7even avatar
UTC

Hooked
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
 
Hooked
@blake7even avatar
1968 Sprint 175, Lambretta Li185S
Joined: UTC
Posts: 289
Location: London
UTC quote
So I got a bit more done.

New cruciform and shaft cleaned up.

External inline image provided by member with no explanatory textimage by Blake7even, on Flickr

Gears added.

External inline image provided by member with no explanatory textimage by Blake7even, on Flickr

new bearing, springs and plates from P200.

External inline image provided by member with no explanatory textimage by Blake7even, on Flickr
External inline image provided by member with no explanatory textimage by Blake7even, on Flickr
External inline image provided by member with no explanatory textimage by Blake7even, on Flickr
External inline image provided by member with no explanatory textimage by Blake7even, on Flickr
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