Modern Vespa

Just got back from a Thursday to Sunday camping trip in the desert with my friends. One of which is the owner of a 63 VBB that I recently added a Vape kit to. Spent all weekend riding around Borrego Springs/ Salton Sea area. This morning, we went out on a breakfast ride and hit some gnarly headwinds. Im not sure if its the headwinds that did it, or some shit gas, but I holed the piston on my trusty 74 Rally.

Motor is a stock cylinder, Pinasco Flytech ignition and a Sip Road 2.0. Jetting is in the mid 120's IIRC. Its been two years since I touched that motor and its been dead reliable. I was full throttle high revs, high load but low speed. Anyone ever heard of that combination causing a holing scenario? Or do you think its shit gas from the desert gas stations?


Beautiful 70* days everyday. Little chilly in the evenings

Indiana. My sisters dog

63 VBB. 2 port 177 kit, 24/24, Vape, Sip Road 2.0 and the rest is stock 8"

Settled on a 160, be3, 135. Wide open for two miles and temps never got above 360*

Nowheresville

Waiting for the Mrs. to come grab me

My two

At least you were on the way home!

This is exactly what happens when the timing is way too strong. If variable timing, it's at least 4 degrees over at the rpm where it holed the piston.

GS 66.5mm piston. Adjust timing, full rejet. If splitting the engine to clean it out, add a 60mm crank to that list. Will go cross country touring with that lot and WOT all the way.

Jack- yes it’s variable timing. Do you mean it’s 4* too advanced for that rpm or 4* retarded. I think Pinasco idles around 24/25 and then retards to 17??? It’s been a while.

Hey MJ....that scooter has been running strong like you said for two years, it would have ran for 5 years, but when was the last time you ran the scooter like you said. That scooter was not used to that kind of punishment especially with the timing being to advanced. If there is a time that the timing needs to be right
on you found it. I can’t think of anything else that would cause that situation other than timing and the engine running lean, or both.

Have not heard from you in a while. Hopefully we can catch up in slo (rom)
Hope all is well scott

Too far advanced. Setting up by the book is where all the trouble starts. Where ever your stator is set move it 4 (approx) mm clockwise.
Going to split it to clean, or hope for the best?

Aye advanced. I’ll do it right and split it. Pics soon

Haven’t forgotten you Scott. Just havent been in your neck of the woods lately. Last time I flogged this one that hard was probably a year ago. Rest of it has been stuff around town/ down to San Diego. I’ll pull the head soon and get back with pics.

Cleaner than I would have wanted it to be. 160, BE3, 128 SIP (125 equivalent

damn! but that is a beautiful scoot nonetheless! Also looks like some great rides out there.

NOOOOOOOO! That's bites. But hey, at least you're in the 60/8 club

Jetting over stock so, hole like that can only be timing.

Going to change the crank? It should be ok, aluminum should clean itself out of the big end bearing but if you change crank, a 60mm is really good in a stock cylinder. GS piston is better in every way over the meteor. If you're going to do the work it might as well be 10mph faster.

[quote="Jack221"] I'm going to remember and do this when I open up my P200

Didn't SIP post something up a year or so ago that they didn't recommend installing their variable Vape kit on a stock cylinder? Whether it was user install with the kit or if the kit doesn't play well with a stock cylinder, one thing is for sure, there has been a fair amount of scooters with stock cylinders with variable Vape and holed pistons. So there is a correlation there for sure.