Modern Vespa

Hello,

I recently took my bike in to have a new clutch installed. Besides being damaged in other ways, the bike starts but will not idle. Unless I am reving it or accelerating, the engine turns off and will stall. Also, my clutch is sticking when it shifts in every gear more or less. Suggestions as to what I can to undo the damage? Where do I start? Thanks in advance for any suggestions! The clutch assembly was purchased new from Scooter Mercato.

Hi, sounds like clutch drag and maybe the idle needs to be turned up?

I recommend you take your rig back to the shop and have them fix these items.

Same as Gick. If the issues appeared after you brought the bike in, they likely didn't test ride or start the bike once the job was done (or did and hoped you wouldn't notice or bother to bring it back). It's their issue to fix.

If it's a cosa clutch, some builds/brands have plates that are too thick and never fully disengage. That's something the mechanic should check with a clutch compressor if the clutch is installed as a whole, or if he rebuilt the clutch, he needs to measure the stack of plates before installing them (<19mm if I'm not mistaken).

Yeah, well, I am already taking the prick to court for what he did to my other bike, so that is not an option. And, to be honest, the whole experience has just been traumatic, there is just no other word. As many mechanic nightmares that people may have, I am quite certain mine takes the cake. In fact, I have been so upset about it that I have not even dealt with this issue, and it has been months already.

So, I was hoping someone could point me in the right direction? Should I remove and try to reinstall the clutch? And why is my engine doing what it is doing? Would it do that if you put the wrong battery maybe? I am pretty sure it was dropped (by the mechanic) and landed on the hub. They also damaged my cowling attachments. Anyway, enough of that. I have put in a clutch assembly on my other PX200, it's not too complex, but I just dont know what to look for, repair wise.

Any suggestions would be much much appreciated! Thank you!

When you say the clutch sticks when shifting into gear, what do you mean? Can you describe what happens step by step?

Sure. When I shift it is tight like it pulls almost? And then if I am not careful it almost jumps a little? It's hard to shift and it jumps a little bit when I do. I hope that explains it. I have been riding these bikes for 25 plus years and it is something I have never experienced before now. The clutch I had installed was the complete assembly sold by scooter mercado. I will check on how many teeth it has

Hi,

Not to be rude, but if you've been riding scooters for 25 years, you should be able to to some basic maintenance by yourself, like changing clutch etc....
(would save you alot of money on labour....)

Anyhow, you should pull out the clutch and check the fitment of the new plates in the clutch basket.
-most likely you need to check the clearence.

Or based on the description of the mechanics doing the work, make sure it is the correct plates for the basket....

Ø

Regarding the idle issue, locate the idle screw, start the engine, and try turning the screw clockwise to pick up the idle. It might be that simple.

As mentioned above, a clutch with tight (or sticky) plates will drag, as the clutch needs sufficient clearance to disengage fully. It would be useful to know which type of clutch was installed: the old-school 7-plate type used up to 1995, or the "cosa" type (8 springs) introduced after 1995. Many people still use 7-plate clutches; many others have installed cosa-type clutches in older machines, so the year of the bike won't necessarily be telling. The cosa clutches are more fussy (especially with aftermarket plates), and the dragging clutch would be a typical symptom of overly thick plates.

The jumping might indicate damaged primary gear (aka xmas tree) springs, which will happen over time. The jumping is usually accompanied by a crunching sound when going down the gears.

A great way to help investigate the issue(s) would be to post a video starting the engine and letting it idle, and pulling first gear, to see firsthand what's going on.

Hi,

No offense taken. I do my own maintenance and I installed my last clutch (assembly) before, so I am not ignorant of what needs to be done, I am just limited on the time that I know it will take me (which for me, is longer than most, as I have a steeper learning curve). I have not used a mechanic in 20 years (not officially), but I did not have the time or the space to get what I needed done, and foolishly believed I could pay a 'professional' to do it for me. Okay. Lesson learned.

Thank you for the suggestion. I will try and adjust my idle and make some space to take out my clutch, if necessary. I doubt I will be able to post a video, but the clutch was the Cosa kind 23 tooth. When you say "clearance" what do you mean by that precisely? Clearance where exactly?

I was thinking maybe the assembly that I bought... Is it possible that the plates got dry while sitting on a shelf somewhere? If I had to best guess my issue, the slight jerk or drag I am feeling would make the most sense to me. If that is the cause (dry plates), is there any way I can avoid having to take the assembly apart and soak the clutch plates?

Thanks again for any suggestions

It's possible they were dry, I wouldn't have expected that to be a major issue though if you have the correct quantity of oil. Not sure how far you have ridden it but simply riding may be enough to get oil on to the plates?

One way to know for sure if the plates are releasing is to pull out the clutch. On the bench you can compress it, either with a clutch compressor tool, or some allthread rod, washers/spacers and nuts. Making sure the spacer only contacts the inner part near the gear, you simply tighten the nuts either side. Once it's tight you should be able to turn the gear by hand fairly easily. This will tell you if it's releasing properly.

If it looks especially dry you could drop the whole thing in oil and let it soak for a couple of hours. Do this with the clutch compressed as above so the oil definitely gets in to the plates.

Thank you. I appreciate the assist. I will keep you posted.

If it's just dry clutch plates, no need to disassemble the unit. Many racers actually advise against soaking the plates first; something to do with the cork expanding apparently.

I usually just spread some oil on the plates as I assemble the clutch with out soaking anything.

In any case, if the scooter doesn't have the broken primary springs issue I brought up earlier, once the idle is set correctly, you can just take off for a ride, and the gearbox will make sure the clutch is under a constant flow of oil picked up by the primary gear.

Oh, and about the clearance: that has to do with the clearance available between the plates when pulling the clutch. The cosa clutch is way superior to the older 6 and 7 spring PX clutches of yore. But as everything is beefed up, there's little space for the plates to move free when disengaged, and with different manufacturing tolerances among suppliers, you often end up with a stack of plates too thick to allow the clutch to disengage fully. To check, you need to compress the clutch with the compressor tool, and verify that you can rotate the basket while holding the inner gear tight without too much drag.