Modern Vespa

I have a 2007 LML motor and a Set of P200 motor pre EFLcases. Going to move as much over as possible from LML cases.


Added this link as it's pertinent.

EFL driveshaft into early PX200 cases

Last edited by Christopher_55934 on Fri Jun 24, 2022 2:56 am; edited 1 time in total

Yes but must use every bit from the LML....ALL or NONE....clutch can be whatever you like that fits the cush drive.

Thank you, I was thinking everything, including the cosa clutch.

I did this swap in my P200 motor a while back. It's a definite improvement.

You need to use the P200 layshaft. The diameter is different on the flyside of the case between LML/PX/EFL and P200-pre-EFL.

Is an improvement in what way? I am not doubting what you are saying, I am just curious. This week I put my hardly uses LML engine with less than 300 miles on it on my Sprint veloce. The flywheel is a 3100grams but the engine is so quiet, so smooth and it idles so well.
The gearing is very short compared to the 200cc engines but I guess it could be a good thing because it feels very peppy.

If gearing is to short you could go up a tooth size. Do you have 10" tires?

In my case, the benefits were two-fold. First, I had problems with it slipping out of gear under heavy acceleration, and second I had problems with "missing" second. Swapping in the LML fixed both of those issues. I already had a 65t primary and kept the 23t clutch, so the gearing isn't too short, either.

Yes, I am on a 10" wheel. I am leaving the gearing as is, I use the scooter mainly in town and I am keeping the engine stockfish for a while.

Hopefully I can try this out over winter, have a set of p200 cases on the way.

Will a P150 crankshaft fit a p200 case? Don't care about rotary valve changes, will be reed valve.

Not familiar enough with these cases yet, could someone use a different bearing? I can't remember what is there.

Nope. The P150 crankshaft is a 105mm conn rod and the P200 needs a 110mm rod.

Forgot about that, I'll have to source a 62mm crankshaft I guess, darn. I'll have to open up cases to fit crankshaft. Hmm a 62mm, rotary valve P200, I bet it would have some torque. Heck squish would be down to sub 1mm without any machine work. I'll have to see how bad rotary valve is, I know it has a half reed ectomy, but you have to take some off rotary valve for a 62mm crankshaft.

It's the diameter of the steel cup in the engine case on the flyside that is the problem.
https://www.scootermercato.com/Scooter-Parts/Cush-Drive/111715

It's not an expensive item.

Engine, Spindle, Cush Drive, VSX - that I understand picture helped. One end is needle bearings?

The part that is the problem is the very end of the shaft. It rests in a steel cup that is pressed into the engine flyside case. On EFL engines like PX/Stella the cup is larger so the end of that shaft is larger. On P200 the cup is smaller so the shaft is smaller. The needle bearings used on them are the same on both.

The fact they use a bushing and not a bearing for the fly side of the primary always blows my mind a little. I mean, it seems to work, but it's one of those things that, whenever I think about it, I think, "This *shouldn't* work."

The spindle doesn't spin. The cushdrive (tree) spins around the spindle and has bearings on both sides, roller on clutchside and needle bearings on flyside.

Doh. Forgot about that.

Mental note: Drink coffee *before* posting