Modern Vespa

Any idears why my kickstart slips sporadically? Could it be the new clutch or is that not a factor? Too much compression from the 102cc kit?

Another issue, I can't get a good seal between the carb, a bellow, and this collar thingy that locks into the tube going to the crank. I'm guessing I have the bellow installed improperly. Is that bellow supposed to surround the entire collar?

Thanks in advance. This frigging scooter is going to be the end of me if it doesn't start this weekend.

+1

On the clutch

Grumpy

What do you mean? +1?

Well, I'm back to no spark. How can I have a good blue spark, put it back together, kick start it, check the spark again and have no spark. New points, coil, felt, wires, etc. Points still have continuity when open. They didn't when I reinstalled it. I am at the point where I can't stand this thing.

One thing at a time or you'll tear your hair out.

Overtight clutch cable can cause slippage of kickstart relative to the top end and a faltering turn-over as a consequence. Try loosening the clutch cable a wee bit and see if you can get the kickstart to reliably and firmly turn the engine over when kicked.

If the kickstart gear is slipping, it may be worn, but I find a couple of taps with my toe at the kickstart helps jiggle things into alignment for a good engagement when I put power behind the kick

Try a different condenser. I just got burnt by a bad new condenser. Since I knew it was new I thought it was a fuel problem. It would start...run for a bit....die and not restart. I changed out the points and condenser again and everything is fine.

On the good side...I have the cleanest carb in the world right now!

I know this isn't the problem, but just a friendly reminder in the kickstart thread to keep that bolt on the kick lever tight. When it's loose the kickstart can slip on the spline, and it will strip all the teeth off the inside of the lever, and the lever will be useless and there will be no amount of torquing the bolt that can fix it.

I've also noticed that some scooter shops are supplying bolts for the kickstart lever that isn't really correct. The bolt needs to have a "shoulder" that comes down into the half-moon notch in the quadrant arm for it to tighten correctly. A bolt that is all threaded is inherently weaker.

Thank you all so much. I finally got the motor running today. The pinasco 102cc kit sounds great. Turns out the points were off and the timing was way off.

Kickstart is still slipping. The bolt was wrong and had to notch it. Grade 8 so we should be fine. It was a pain....

Now on to wiring the switch. Switch numbers aren't Exact.

Then hopefully the clutch will break loose when I finally bump it in gear.

Almost there....

You mean the little bolt that pinches the lever onto the kickstart spline?

Go ahead and order yourself another kickstart lever then. Trust me on this one. They are made of aluminum, once it slips once and strips off those little teeth it's just a matter of kicks before it will round off inside and you'll be stuck bumpstarting.

You can torque that bolt to a million, but if those teeth have shaved off on the inside of the lever you're just a matter of kicks before you're stranded, or bumping it like a racer...

Go ahead....ask me how I know

Yup, order another one as a spare, and make sure it has a carriage bolt, not a bolt with threads all the way to the head.

This is one occasion when LML are better than Piaggio - they make a nice steel kick start lever, much better than the softer alloy OEM ones.

Hmm....I think I'd rather have the kickstart lever strip before the kickstart quadrant shaft. If the shaft strips, you're splitting the cases. If the lever strips, just throw another one on. It's designed to be softer than the shaft for that very reason.

My guess is that the LML lever is softer than the quadrant too, hopefully so.

There's soft and there's soft. When kickback can strip a brand new oem (read made in India) kick start lever freshly torqued to spec, I'll risk a stripped quadrant.

The kickstart is slipping inside. It's not missing a gear - well, it misses occasionally and I can feel the tooth slip off. But this slippage is an engaged smooth slippage. No grinding, or jerking. Just a smooth resistance like something is spinning around a shaft - ie, I think the shaft is slipping around the shift gear. I just don't know...

And I can't understand if it's related to the fact that I installed a brand new clutch.

Loosen clutch cable all the way..

Also are you 100% on the key seating home? Did you torque the clutch nut to spec? Both pretty common errors in smallie clutches.

Other then those things check the arm/level below ther motor with the cable slackened(hopefully screwing the barrel adjuster in will do this).. The arm should have a tiny bit of movement, maybe 1/8-1/4" before the (brass)plunger hits the clutch. Kinda hard to explain since it's a feel thing, but since you replaced it yourself you should get what I'm saying..

beyond those you may need to go back in..


Good to hear you got it going though, your almost there, and just in time for riding season

See my post above - it sounds like your clutch cable is too tight, such that the plates are never firmly planted against one another. This can cause the kickstart to feel like it's slipping "through thick butter". If you're WAY too tight it won't even feel like that and it will just plunge to the ground when you kick it. But it sounds like yours is just tight enough that against the compression in the top end the plates will slip.

It's easy to rule out - loosen the solderless nipple completely so you know the cable isn't pulling on the clutch arm at all. I'm guess the "slipping" feeling will go away.

yeah, what Plum said.

Okay guys, I'll loosen it all the way tonight and report back.

ProfPlum, I'm not sure what you mean by the " key seating home." I also, didn't realize there was a torque setting for the clutch nut. Crap!

Xantufrog, That's a perfect description - pushing through butter. So the clutch plates are engaged?

This problem has to be related to the clutch not being able to shift the gears (I haven't driven it with the new clutch, just tried to shift gears when I installed the cables). This happens on minibikes sometimes. Usually, if I can get it going and get it in first or second, the clutches break free. But I'm thinking now I need to pull the clutch and retorque it.

Okay, I'll let y'all know.

ProfPlum - did you see the '78 p200e in b-more? Just sent a message asking about it. If it's still available, I'm going to make an offer unless you want it.

Actually this would be a symptom of the clutch plates NOT being engaged. At least not fully. At rest, when you aren't squeezing the clutch lever, your clutch should be engaged, linking the top end with the gearbox. When you pull the lever in, the clutch disengages, taking power from the top end off of the gearbox for smoother shifting. If you have the clutch cable too tight, however, then even when you aren't squeezing the clutch lever, it is as if you were (at least a little). This means the clutch may slip against the compression of the top end when you try to turn the scooter over.

Gentlemen, start your engines! Clutch cable was too tight. That problem is resolved. Rode the scooter for the first time tonight. Very fast for a "50" - actually a 102cc. Drove it with no clutch. Will reassemble clutch cable tomorrow night and see if it breaks loose. This thing is running great.

Now, on to the electrical issues.... Dang bulbs are blowing with increased rpm speed. Might be a result of trying one bulb at a time. I get about 7V at the junction when revved up. About 2.3v at the bulb at idol. Since there isn't a voltage regulator, I'm assuming that the bulb resistence is used to lower the voltage. Also, I might need to bump up the bulb watts. to 10 (rear) and 25 (front), or install a voltage regulator in each line.

Thank you all very much for your help. That's awesome... I'm flying high tonight. Can't wait for the weekend to finish up the tuning... Now to order more bulbs. I'm thinking of installing some inline fuses.

Curtis

Getting close

now thats a nice and clean bike u got there

Curtiscohen, I hope its ok that I borrow your thread.

I am putting together a 50S V5SA1T 1976 and have some engine problems.
Its been a long project, 12 years since I took it apart:)

I am not sure how much I took the engine apart, I might have taken the sylinder off and some of the side covers, but no complete rebuild.

Not much have happened the last 12 years, but a lot have happened the last two weeks, and today I finally put the engine back on the frame.

Now to the problem.

- Tried to start. But the kick started got stuck after 10-20 attempts.
- Shifted gears, tried to roll it, and after a while I got it working again.
- Now it does not start and the kick starter is slipping every second or third time. Is excalty like the case above (like hard butter). No noise, and no problems between the kick starter and the axle it is mounted on.

But in my case the I have not yet mounted the clutch or gear wires (I can change gears without using the clutch).

First of all I have to get the clutch working again, what to do?

Second, why did it get stuck? Should I check the sylinder and piston?

Hope some of you Vespa experts have some wise tips.

I will be replacing the kickstart lever as the teeth have gone on my original one. What torque settings is correct for that bolt. Cannot find it anywhere. Rally 200. Thanks