Modern Vespa

My PX (modified) goes like a rocketship until I get into 3rd at about 65, and it stops accelerating at the same rate, it runs fine, but stops pulling.

Thoughts?

Is this where I can ask my Durkopp, Heinkel, IWL, Cezeta, and Valmobile questions too?

Sure! Though we won't guarantee that anyone will answer you, or even know WTF you're talking about...

Like anyone ever understands any of my other posts?

Good point.

Have you thought about swapping out your 3rd and 4th gears to ones of a ratio that better fit where your topend / pipe make peak power? I know you're asking this facetiously ... and are probably already aware of the oddscoot yahoo group. ( do you actually have one of all those scoots? )

Didn't know there were options, with gearing - hmmm time to do more reading.

I watch the yahoo group - they're a little serious for me (imagine that.) Nice helpful people though.

Of course!

What year is your PX200 ? If it doesn't have an EFL gearbox it in, consider going to that one ...it's got a much nicer gear ratio with less of a flat-spot between 3rd and 4th.

Some people take the 4th gear from a T5 and replace their 4th gear with that.

Just look at all the choices in the P-series gearing calculator. You have a lot of options .... not as many as a lambretta ... but a lot.

http://www.scooterhelp.com/tuning/vespa.gear.calc.html

I was also going to suggest that your gearing sucks. 65 in second???

I'll have to look at the engine number to confirm what it started out as - if there are options; admitting my lack of info/knowledge at the moment.

It's 65 in 3rd; in 2nd, well that's crazy talk.

Oh yeah, I'm on 'Under the penalty of death,' scooter/motorcycle restriction at the moment.

I'm thinking about offering to get a mistress, to see if that would be an acceptable substitute; so I can get get back to collecting scooters. Cheaper too (from what I've heard.)

What i hear you saying ... ( and it's a common complaint for people with kitted P200's ) is that you rev out 3rd gear and get as far as you can ... and then switch to 4th and there's NO acceleration - it's almost like you're cruising along at the same speed.

Am i right?

You are right. I've also just read that engine braking is bad?

I'm going to mount the new video camera to it, go for a ride and post it on YouTube in a couple hours. It will be freaking awesome....

I downshift all the time to slow down. There's certainly no GOOD that can come of it.. but i don't know that it specifically HURTS your engine. I'll have to talk to John about why he thinks that's the case.

+1, almost. Can extend brake life = GOOD.

Been doing it for some 44 years now, 41 of them on the same VNB.

IMHO, Eric, I think this comes from the warning in the premix engine owner manuals against extended downhill riding with the engine in gear and the throttle closed, which can, indeed, result in under lubrication. Taken to an extreme, this warning is overinterpreted to mean no engine braking at all, which is not what the manual says.

Al