Vintage vespa with sidecar
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Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
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Location: california
Fri Jul 24, 2020 9:45 am quote
Voodoo - much appreciated. Its a ton of fun to ride - and I'm indebted to this crowd. Hatching a plan to do some work up in Oregon - making my way there by working my way up the coast with the Orange Unicorn loaded in the back of the truck.

Pheas' - Ha! Well, I did have 10 liters of fuel, a spare wheel, a bag of tools, and a six pack of beer - just in case...

Jack - the additional ping marks all occurred using an EQ rod - and your basic premise is right - I was compensating for the first 1/3-1/2 throttle. That's why I got some EK rods to experiment with.

For sure I am on new ground here with the Smart Carb. Those guys don't have the depth of experience with Vespa motors that they have with two stroke dirt bikes. In their defense tho - I knew that going in and offered to help provide some feedback and data. Making myself a worlds foremost expert in Smart Carb for Vespa jetting. 🙂.

The steeper taper rods allow me to be richer WOT and leaner small throttle now. I've been mapping the piston top after ea. major ride with new rods. The 60+ mile ride before and after are below. The EK rod appears not to have added any new marks - and let it be said - I was not kind to it when we ran in the hills.
Quote:
I think you're changing the plan and going to run the MHR bolt on next. It will be interesting how this compares with the bolt on BGM. But both a bit of a yawn compared to the tuned versions.
And now you know why I hadn't ported/lifted the BGM...
Took a bit longer than expected to get the 57mm MHR kit.
Think it's better this way for a number of reasons.
- Out of the box comparison.
- Longer time on the BGM to get a better sense of it
- No rush on the work - I can be riding the Malossi while I tune the BGM

Question - can I polish out the marks on the piston top so it start's fresh as I tune? Worth it?

IMG_6611.JPG
July 11th - had not received the EK's yet - had leaner tipped EQ rod. in than I am running now in an EK.

IMG_6720.JPG
July 22 - EK rod allowing leaner bottom and richer WOT. Shot after the SoCal/MJ ride. No new ping marks - tho it was run hard and long.

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Fri Jul 24, 2020 10:15 am quote
The EK rod is running better but still not great. Still maybe too rich and too lean but less than before. You have a sound recording of the whole rev range on this EK?

Think you should quickly do the BGM. Will save taking the piston off twice. Will only take a few hours. Then once run for a while change to Malossi and never look back.
The MHR tuned is going to be really something.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Fri Jul 24, 2020 10:34 am quote
Quote:
The EK rod is running better but still not great. Still maybe too rich and too lean but less than before.
What are you reading that I'm missing?
(Plenty of room to go richer or leaner at both ends. Give me your $.02 on what you think it needs)
Quote:
You have a sound recording of the whole rev range on this EK?
Tried to capture. Was kinda crappy sound.
Will see if I can improve - and post.
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Fri Jul 24, 2020 1:20 pm quote
If that needle was any good there would be no silver showing by now. You've mentioned 4 stroking at mid rpm. Which explains the silver. If you fix the mid the top will be even weaker. Means you need a needle even more pointy than the EK. Maybe just the next one up. Or next two ready for the MHR.

This is normal. Two strokes that really go need to have pointy needles. And if there is not pointy enough, thats what dual taper needles and/or power jet carbs are for.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Fri Jul 24, 2020 1:59 pm quote
Hmmm.
Suspect some things lost in translation.
But there also may be a difference of opinion on what is optimal/ how the levers effect that target.

On the lost in translation front:
I try and post the relevant facts - but plenty left on the cutting room floor.
That may leave some opaque areas - tho you are pretty good at reading from afar.

I did 50+ miles on an EK jet - and the piston colored out near the edge.
Pinky nail of wash left at the ports.
There was no new ping marks - and that was with WOT 4th gear long pulls up hills and a Sidecar loaded with tools/gas/ and a spare.
But when I got back - I moved to a leaner jet to see how that was ~ 10-15 miles of riding and some WOT speed runs.
It is probably a little lean with that one.

On target and levers:
As I understand it - you don't want it black to the edge - but rather washed about a pinky nail worth.
More fuel (richer) will wash more - so black to the edge would make me too lean - and a thumb nail or more too rich.

Your point on two strokes that really go using pointier needles - makes total sense to me. The EK give me that - but I have lots of tools at my disposal if they don't reach rich enough. A little lapping of the end of the needle and some careful measures can allow me to make the WOT position match an even richer needle - without putting a power jet in. But honestly - I don't think I need to go there. With no pinging - and a pinky nail of wash - and no 4 stroking down low - I think the one I ran with SoCal/MJ ride was spot on.

The reason I tried leaner on return was because its easy and I can't leave well enough alone. Speaking of which - even the needle I ran with SoCal/MJ was hand lapped down at the WOT position to match an EQ needle tip width I liked.

-CM
Addicted
bare metal cafe racer
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Fri Jul 24, 2020 5:31 pm quote
charlieman22 wrote:
Pheas' - Ha! Well, I did have 10 liters of fuel, a spare wheel, a bag of tools, and a six pack of beer - just in case...
But no stuffed dog??? Reckon the only thing that would turn more heads than the orange unicorn would be the addition of a furry friend.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
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Fri Jul 24, 2020 5:34 pm quote
CM do you have a final dyno with this needle - to cap this phase of development? That would be good to see the comparison later on.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Fri Jul 24, 2020 6:44 pm quote
Quote:
CM do you have a final dyno with this needle - to cap this phase of development? That would be good to see the comparison later on.
Fixing a snapped shift tube this afternoon.
Tomorrow I will do a final set of runs.
Can post both for best needle and sound.

Jack - was on the run earlier but typed that out quickly.
Keep in mind - the needles are fixed - unless I sand them down...- but I have adjustment over the idle end with the clicker screw.
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Fri Jul 24, 2020 10:52 pm quote
Black to the edge is good. Once you get this far and a bit more, gold spots will appear near the transfers.
The thing that suggests jetting issues is silver. Don't want to see bare aluminum. If it hasn't seized up, this always means too rich at the bottom and too weak at the top.

As bolt on 187 this is still at very low port timings when compared with motorbikes, so not going to need any power jet or complex needles. Just a straight jetting job.

Get the cylinder off and tune it. Will save a lot of time jetting. With the low blowdown it's going to be sensitive.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Fri Jul 24, 2020 11:35 pm quote
Quote:
The thing that suggests jetting issues is silver. Don't want to see bare aluminum. If it hasn't seized up, this always means too rich at the bottom and too weak at the top.
That's an interesting insight
I've plug chopped a 29 rod already.
It was an EQ series - but the number reflects the tip - which is felt at WOT - and that's all you see with a WOT plug chop anyway.
(The letter reflects the taper to that tip - which is felt at the bottom.)

That 29 looked a hair lean based on the chop.
Figured a 28 would likely be the ideal.
So I ran the 28 with SoCal & MJ on that ride.
But I did it with an EK rod - meaning it was leaner down low.
Ran like a beast.

That said - I just popped it in and did virtually no tuning.
With a leaning twist of the nob though - suspect I could turn the silver on the piston to golden brown.
There was plenty of adjustment left.

Will it feel any better than it does?
Hard to believe it could - but maybe!
Only one way to find out.

Hope I can get a decent recording of the sound.
That alone is worth the price of admission.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Sat Jul 25, 2020 10:48 pm quote
So my broken gear shift tube turned in to a day long project - so no window for a ride really - which is not to say that I didn't drive it to the pub at the end of the day and sip a quick cold beer on their patio.

The MHR arrived and I had a chance to unbox.
It's a skeleton of a cylinder - with only little bridges between the ports - and one right down the center of the exhaust port.
Looks like there is not a lot of room for grinding:
a. because they already did it
b. because the stud holes are already close to the exhaust port(s).

That said - the bridge between the two exhaust ports looks like they ground all the nikasil off? Have a look. Disappointingly, this one might be going back.

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The most exciting moment. New in the box

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Oooo. Ginormo ports everywhere

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Quick sketch to s(e)ize things up

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Record scratch sound. Seriously - how does something like that leave a factory. chamfers are also haphazard. would have done better to receive unmolested and molest it myself.

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
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Location: London UK
Sun Jul 26, 2020 12:08 am quote
There's actually quite a lot of room for grinding. Doesn't take much to get the power up and you'll only be in the exhaust port, so won't take long either. It will be risky but sure you're up to a challenge.

The exhaust bridge doesn't look good from here but might be some technique for thicker nicasil. It being the high wear point. Is it flat? If it is run it. If when you take it off to tune it and it's looking bad then send it back. You'll have done the deed on the BGM by then and that could go back on.

The Malossi chamfering always looks like the apprentice did it. Runs fine and at least it's deep. Piston will need chamfering.

How's it measure compared with the numbers we had before?
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7706
Location: Victoria, Australia
Sun Jul 26, 2020 2:27 am quote
I'm thinking that it's like that on purpose.

Imagine - what is the hottest part of that cylinder? Yes. So when it expands, where does it expand to? Does nicasil survive the kind of expansion? Possibly not.
How far does the ring need to come out before snagging, and is that more than what that recessed bridge allows? Imo, probably is.

This Parmakit W Force cylinder also has a different colour bridge, looks like no nicasil on that either. I didn't look any further, but I reckon a two-stroke engineer would probably know this already.

Clipboard01.jpg

Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
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Location: california
Sun Jul 26, 2020 8:08 am quote
Quote:
This Parmakit W Force cylinder also has a different colour bridge
Good find! Looks like it's a thing. Have to say - looking at it again - not sure how someone could do that by accident - unless the whole cylinder had that texture before they plated - and they simply didn't plate the center divider.

Did an image search and found this - its a 70CC but appears to have the same texture. Zoom in on image below.
Quote:
Is it flat? If it is run it. If when you take it off to tune it and it's looking bad then send it back. You'll have done the deed on the BGM by then and that could go back on.

The Malossi chamfering always looks like the apprentice did it. Runs fine and at least it's deep. Piston will need chamfering.
Chuckled - good description.
The design of the cylinder is cool.
It is soooo open.
Ill get some measures today.
I didn't bother to put them on the first tracing due to accuracy.

Noted this from prior post:
Quote:
Get the cylinder off and tune it. Will save a lot of time jetting. With the low blowdown it's going to be sensitive.
Can you clarify your comment on blowdown sensitivity? Didn't follow.

m318440_zylinderkit_malossi_mhr_minarelli_lieg_ac_web_800x.jpg

Hooked
79p200e 66smallstate 85pk50xl 84p125ets 63GL150
Joined: 24 Nov 2016
Posts: 168
Location: Flatness, Tx
Sun Jul 26, 2020 8:31 am quote
Ginch has it.
Bridged exhaust ports are notorious for seizing right at the bridge.
NSR pistons below show holes in piston right at the bridge for lubrication from underside to help alleviate seizure at the bridge.
Remedies are to grind the bridge back (relieve the bridge), or add lube at the bridge. I wouldn't drill holes in your piston as the big clearance where your bridge was ground down would possibly leak exhaust back into lower crankcase through the holes.

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Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
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Location: california
Sun Jul 26, 2020 8:44 am quote
Thanks PD.
Funny - was just reading through your GL thread.
What a great find!

I have always been curious about the piston holes.
On some, it looks like they are divots - similar to a golf ball - rather than holes.
Perhaps this is to cary some extra lubrication - without leaking?
On that piston you posted - do the holes go al the way through?
Hooked
79p200e 66smallstate 85pk50xl 84p125ets 63GL150
Joined: 24 Nov 2016
Posts: 168
Location: Flatness, Tx
Sun Jul 26, 2020 8:52 am quote
Hey CM. Thanks.
Your leaner is so unique and cool!


Holes go all the way through.
Here is a link to Wiseco and what they recommend when buying new pistons from them.

https://blog.wiseco.com/two-stroke-how-to-relieving-the-exhaust-bridge-and-drilling-lubrication-holes
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Sun Jul 26, 2020 1:32 pm quote
charlieman22 wrote:
Noted this from prior post:
Quote:
Get the cylinder off and tune it. Will save a lot of time jetting. With the low blowdown it's going to be sensitive.
Can you clarify your comment on blowdown sensitivity? Didn't follow.
Low blowdown reaches saturation quicker making the fuel curve more curvy. Makes it difficult to get all jetting points in perfect. Especially above half throttle. Will be able to get reasonable eventually but you'll see after it's tuned, will be very different and jetted in an afternoon.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Sun Jul 26, 2020 10:23 pm quote
Poidog - that one is in my saved file.
Excellent stuff.
Thanks!

Jack:
Quote:
Low blowdown reaches saturation quicker making the fuel curve more curvy. Makes it difficult to get all jetting points in perfect. Especially above half throttle
.
Interesting - so the Malossi should fix that anyway.

I think the silver you see on my piston is from low end of throttle. Maybe as much as 1/3.
Scoot is running really well as is
I have experimented with different "needles" at WOT, done plug chops, and Dyno runs. The slightly leaner tip 29 (WOT) is the fastest of the lot producing the most absolute peak by about 1/2 HP.
There are diminishing returns as I get leaner.
A hair richer tip produces about the same - perhaps a touch less HP at peak - but likely the most robust.
Have a look below at final results on stock BGM.
We can optimize the last 2% of the throttle once the new cylinders are on.

Managed to record a couple speed runs as well.
Max speed matches the max HP from the chart -I get about 56 with the leaner 29, 54 with the slightly richer 28.5.
Decent rendition of what it sounds like.

EK29:
https://youtu.be/0cQmeMhruxU
EK 28.5 - (slightly richer):
https://youtu.be/eLv4q8QGLBs

Malossi numbers and some calls will post tomorrow.
Cheers.
CM

Screen Shot 2020-07-26 at 10.15.35 PM.png

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Plug after 50+ miles today. Highway in 90 heat/ 4th gear hill climbs/ mountain roads - steep. The works. No additional ping marks.

IMG_6811.PNG
arriving at the ocean - gorgeous day for a ride

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Sun Jul 26, 2020 10:47 pm quote
Watching the BGM, first thoughts are it seems a lot slower than the Polini. Looking forward to see how the bolt on Malossi does. Sure it will be better than 15 bhp, how much though?

One extra thing confusing the jetting is that 100 octane mix. Should start using regular pump gas. This is the best thing to jet with as it's always the same (a bit crap). With the set up on this gas you can run any gas from anywhere and it will never blow up. 95 RON E5 is all I ever use in all mine (bikes too). You should use your 90 MON, as it's the equivalent over there.

Get decent measurements from the Malossi before it's run. Once you feel the MHR run, I think we may never get to see the BGM again but we always have Sime's tuned one, when engine #3 eventually gets its day in the sun.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
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Location: california
Mon Jul 27, 2020 1:31 pm quote
Quote:
Watching the BGM, first thoughts are it seems a lot slower than the Polini.
Yes and no.
Keep in mind these are measured with WOT only - not a range of throttle positions.
What stands out are two things.
1. The Polini had more power at peak - but not by a lot.
2. Now look at the over-rev range. 8K RPM. The Polini had 2HP more. That's a lot.


8K RPM = 54MPH on my bike.
So what you are seeing is really exacerbated at 8K RPM.
I suspect that is pretty well all in the timing.
Polini was 123/177/27
BGM is 123/173/25
It just doesn't have the timing at the top to produce power there so no matter how big the exhaust port in width - it is limited by port timing for power at high RPM.

screen_shot_2020_04_20_at_41515_pm_10083-2.png
Polini chart - 123/177/27

Screen Shot 2020-07-26 at 10.15.35 PM.png
BGM chart - 123/173/25

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
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Location: London UK
Mon Jul 27, 2020 1:47 pm quote
The Polini pretty much has 2bhp more at any rpm and peaks 500 rpm later. At 10 bhp against 12, that's 20% more. If these were off the shelf kits, people would only buy the Polini. With the BGM tuned like Sime's the tables would turn completely. I am sure the tuned BGM would go over 20bhp with no mid losses. If you imagine the 5000rpm point continuing to 8000, that will be something like the power. The Malossi tuned will definitely be over 25bhp.
Time to continue experimenting. Which next step will it be?
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
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Location: california
Mon Jul 27, 2020 3:00 pm quote
Malossi MHR timings with 57mm kit on a 60mm crank
Here we go:
Internets say the 57mm kit on a 57 mm crank produces the following timing:
119.2/178.2/29.5 with a stated PBT of .2
If I extrapolate from that - using an online calc - it would mean the measures on the cylinder should be 33.09 from deck to ex. port top and 46.04 deck to transfer port top.

Made some careful measures without looking at the above first - and got 33.37 and 45.85 respectively. Pretty close
So working with my measures, and a .2PBT (.7 squish), lowest possible timings would be 133/184.6/25.8.
For reference -the 60mm Malossi kit bolt on is 122.5/178.5/28.
Why are we taking them so high with the 57?
Concerned about peakiness and pull down low - even if it has a reasonable width of power band.

IMG_6817.jpg

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Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
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Posts: 2226
Location: London UK
Mon Jul 27, 2020 9:41 pm quote
Nice measurements. Last time we discussed this there was going to be a head gasket on the Malossi. Going from the actual numbers with a 0.2 base gasket, the PBT would be -1.5mm, so the head gasket could be 1.5mm to put PBT by back at zero. Or whatever makes your squish happy.

This would be the best comparison with the BGM. Once the direct comparison declares the Malossi as awesone. I would like to see it tried at 0.7mm base and 1.0mm head gasket, then onto some Dremel work based on the results.

Did you buy packers? Or going to be making them yourself?

Edit: Oil holes. These are really only needed on forged pistons. Yours isn't. If too big or not accurate they actually cause the seize.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
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Mon Jul 27, 2020 10:03 pm quote
Covid time has you sleeping in past sunrise.
Find that highly inconvenient.
Numbers did seem weirdly astronomical to me.
Was sure 131 was not the TR starting point!
What the hell is Jack thinking - has he got the Covid?
But now realizing I am mixing apples and grapes.
Shorter 57 cylinder will give me significant negative PBT.
Head gaskets don't change timing.
Need to scroll it on my garage wall - confuses me every time.
I can lift it .2 for example - and still have control over squish with head gasket thickness.

Looks to me like the head has a .5 squish band based on the literature and measure.
They recommend .7 squish (just keeps getting smaller)
Do we wanna go with that?
Would mean a .2 PBT would be the ideal (thats why I had that in above calcs)
Have a whack of head gaskets in stock - and various thickness sheets of copper should I need to fab something myself.
Quote:
Or whatever makes your squish happy.
In contention for my next signature.

Edit went back to calculator - now reflect the -1.3 PBT that I will get with the 57mm kit with a 60mm crank adding 1.5mm (half the additional 3mm).
The 57 kit starts at .2PBT, thus the additional 1.5MM takes it to 1.3mm above the top of the cylinder.
Timing with what ever base gasket they assumed would be 125.5/179/26.75
Not sure what base gasket they assumed.
Kit comes with .1,.15, & .27

Also - noted some bosses on the head near the stud holes. Anyone with experience in dealing with this relative to the head gasket - welcome your insights!

images-6.jpeg
133/185/26 timings in action

IMG_6820.JPG

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
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Location: London UK
Mon Jul 27, 2020 11:36 pm quote
Covid time is great. Can do what you like when you like. Who wants to go to work anyway. I doubt you are when going to bed so late.

Port timings are going to be bigger on the Malossi and the angles are too. Will be ok on that box exhaust but the Malossi on higher porting would really come alive with a targeted (made for certain port timing) expansion. S&S do some really quiet silencers.

Edit: The different base gaskets in the kit reflect how each engine will need a different gasket to achieve 0.2PBT.

Cut the head gasket to fit. There should be alignment pegs to negotiate too.

133/180/24 is not a dragster. Put the exhaust over 200 and it might be.

Could be running by Tomorrow, if you don't sleep in too long.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
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Tue Jul 28, 2020 12:01 am quote
You forgot to mention reeds.
🙂
Just posted an edit above with the timing calcs corrected.
Its a notch up from the BGM - as you note.
Based on my experience so far - that will be an excellent upgrade to the already well liked.
Can't wait to try it out.
Just have to run an errand this week first.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7706
Location: Victoria, Australia
Tue Jul 28, 2020 1:45 am quote
So does the 25hp carrot rely on an expansion chamber? If so that's changing the rules after the competition has started.
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Tue Jul 28, 2020 3:45 am quote
charlieman22 wrote:
You forgot to mention reeds.
🙂
Just posted an edit above with the timing calcs corrected.
Its a notch up from the BGM - as you note.
Based on my experience so far - that will be an excellent upgrade to the already well liked.
Can't wait to try it out.
Just have to run an errand this week first.
Go with the -1.3PBT for the bolt on Malossi. Squish at 0.7mm is good. Near maximum but good. Be accurate.
As bolt on this should do over 20bhp on these timings.
Ginch wrote:
So does the 25hp carrot rely on an expansion chamber? If so that's changing the rules after the competition has started.
Tuned the Malossi should do 25bhp on the box exhaust with 25mm smart carb. If reed, 35mm carb and a targeted expansion could even be 30bhp. Might even still pull the sidecar with a passenger if we're careful. However, with CM still doing non scooter stuff it could be next Christmas by this test.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
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Tue Jul 28, 2020 7:50 am quote
Quote:
Ginch wrote:
So does the 25hp carrot rely on an expansion chamber? If so that's changing the rules after the competition has started.
Tuned the Malossi should do 25bhp on the box exhaust with 25mm smart carb.
Quote:
with CM still doing non scooter stuff it could be next Christmas by this test.
Comparing the BGM to the Sport would have been the more natural play - but in the end might have been more a splitting hairs discussion over 1HP here or there.
Interesting - but not sure the juice woulda been worth the squeeze.
Suspect they are both good cylinders in their own right.

I use this scoot for touring not drag racing.
Sounds mundane - but in a single outing I might go 50-75 miles and mix 6 lane highway runs with curvy long mountain climbs.
Fast is fun but torque is essential - and I don't wanna run outa gas.
(Wish all y'all could all join for a ride!)

Now that I've really gotten to know the BGM - I can see that a bit of tuning and port elevation is going to optimize for my use.
The MHR could be even more of a challenge to tune in.
Max peak power is nice - but I'd trade 20HP with great pull over 25HP of scream machine - any day.

Im really interested to see how the "sportier" MHR fits my style.
Thus the move to compare stock BGM to "Stock" MHR - before we start molesting the cylinders.

Gonna be fun.

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Typical ride

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Target curve.jpg
Ideal looks something like this

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Tue Jul 28, 2020 11:04 am quote
charlieman22 wrote:
I use this scoot for touring not drag racing.
Sounds mundane - but in a single outing I might go 50-75 miles and mix 6 lane highway runs with curvy long mountain climbs.
Fast is fun but torque is essential - and I don't wanna run outa gas.
(Wish all y'all could all join for a ride!)
This is not going to be a racer but the 30bhp reed version might be getting that way. At 25bhp peak power will e higher but if done right the bottom end should all still be there, as the 25bhp curve will envelope the 20bhp curve. Going faster and emptying the tank will be a choice. There are touring expansions, many of them, this is what I was implying.
If the bolt on test works the tuned one will too. We will see soon
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Tue Jul 28, 2020 12:58 pm quote
Quote:
At 25bhp peak power will e higher but if done right the bottom end should all still be there, as the 25bhp curve will envelope the 20bhp curve.
We manage to get north of 20 and envelope the existing curve - I will be well impressed.
Got some tools for measuring - hope to supply enough info to allow you to twist the nobs successfully.

Now - about that errand...
http://modernvespa.com/forum/post2420210#2420210
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Thu Jul 30, 2020 9:06 pm quote
California Dreamin'
Well - that may be the film playing in my mind when I am on my death bed.
I'm not sure I would do it again alone - that is a trip best made with company - but that was one spectacular ride.

50 miles of rugged coast line along Hwy CA1 between Carmel and Big Sur.
In classic form, I completely underestimated the ride.
Long winding climbs and descents with hairpins mixed in and buffeting wind gusts.
If you wanna have a laugh - some moments are here:
https://youtu.be/jwzZRMJ6ycE

On the way out - it was like flying. On the way back - in to a head wind - I tucked the chin of my helmet on to the headset, drew my elbows in tight to my body, and leaned on the BGM relentlessly the whole way home.
That thing has my respect - it is one hell of a cylinder.
Editors note: - have to remember to show you guys and gal what I got while I was here running errands.
🙂

That was a memorable day from Covid time.
-CM

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Loaded up and ready

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A beauty shot at the beach before I started off. Seemed so peaceful and calm at this point

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Another along the route

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Had to shut my eyes for 10 min before I drove back - so flopped in the sidecar

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got back to the perfect dinner

Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2226
Location: London UK
Thu Jul 30, 2020 10:58 pm quote
Looks like a great ride. Quite an adventure and one to remember. Stayed running the whole time is always good. Crown check is hopefully uneventful after that.

That BGM sounds like it's working hard, should have been tuned ages ago. Seems to be in the overrun quite often. Tuning would make it not need so much effort.

I wonder what you picked up that is of interest to us. New scooter, maybe a 200 motor. Crate of wine. Probably a surprise.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Fri Jul 31, 2020 6:49 pm quote
I did a poor job filming really - was mostly focused on the ride - but got a bit of vid that I shared.
From this date forward - no one can say anything bad about the BGM cylinder.
That thing is a horse and I will defend its honor.
4th gear, up hill, throttle pinned, in to a head wind - that covered any damage I might have been doing cause I couldn't hear.
Will be interesting to look at that piston crown - if it still has one.

Now - about that errand I was running...

So a funny thing happened last week.
Found a completely knackered 57 Allstate handlebar scoot for sale - cheap.
The price accurately reflects the condition...
Trust me...

That said - have harbored an electric scoot concept for some time.
Love the styling of the handlebar models - and wouldn't want to trash an original/ restorable one - so felt I had to pull the trigger for this hulk of rusted steel.
At some point - this will be a new thread.
Below - in all it's glory.
Now in my garage.

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bagged

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She's seen better days

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Came with cowls and motor

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believe it or not - this is its "good side"

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"Beauty" shot

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Gracious. Lynn - I'm gonna need some help on welding in a floor board

Molto Verboso
1963 VBB2T
Joined: 07 Nov 2012
Posts: 1919

Fri Jul 31, 2020 9:17 pm quote
Oh wow another project. Love the relaxation pics.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7706
Location: Victoria, Australia
Fri Jul 31, 2020 9:26 pm quote
Looks like a fun ride CM! Pity nobody came along to try to keep up with you...

Nice project base. Looks generally straight too.
Style Maven
74 50s x3 78 P200 84 Cosa PK50XL2 58 AllState 68 Sprint 80 50special '66(?) Super125
Joined: 22 Nov 2010
Posts: 7799
Location: seattle/athens
Sat Aug 01, 2020 6:02 am quote
Oh man, I can't wait! So, have you narrowed down your sourcing for motor and batteries yet? Top speed goal?

You got the hard to find gas tank and cowls and front end all there and on a pretty good frame, but for ugly hole in the bottom. But as long as the tunnel is cancer free, you can fix that well and take advantage of the access.



Will you add a sound system playing revvy 2T motors at the touch of a button?
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1520
Location: california
Sat Aug 01, 2020 7:19 am quote
Quote:
Pity nobody came along to try to keep up with you... Nice project base. Looks generally straight too.
Ha! yes it was a shame. That ride best made with two or a group.
My wife and kids were less charitable with their comments when they saw me unload the new project...
Quote:
Oh wow another project. Love the relaxation pics.
. was so wiped out from the ride at halfway - chose to nap for 10 with hat over eyes!
Quote:
have you narrowed down your sourcing for motor and batteries yet?
It will be a QS motor and Kelly controller - but I haven't decided yet if it will be a hub motor or a mid drive motor mounted to the swing arm. likely a 72v system
Quote:
Top speed goal?
To make up for the lack of 2T je ne sais quoi that I will miss terribly - I plan to make this thing run 60+ and be Tesla fast getting there.
Quote:
But as long as the tunnel is cancer free, you can fix that well and take advantage of the access.
Good eye. Tunnel appears to be very solid still - but plan to bead blast everything and see what I really have. The plan is to put an internal frame inside the tunnel that incorporates mounting points for the swing arm - before I weld on a new floor board.
Quote:
Will you add a sound system playing revvy 2T motors at the touch of a button?
Best idea of them all!
bodgemaster
1963 GL, 1976 Super (x 2), 1974 Primavera (x 2), 2006 Fly 150
Joined: 26 Sep 2013
Posts: 5333
Location: So Cal
Sat Aug 01, 2020 8:15 am quote
New project in da house

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