Cosa Clutch

Hi All

Upgraded my LML 125 last year with a Pinasco 180 and 26mm SI with help from Curare and Adrian N. Now the scoot gets up to a top speed of about 60mph (100 km/h) quite quickly. The speedo actually shows closer to 65mph but I know the speedo is generous as I clocked the bike against a police digital speed checker near my house. I’m sure there’s a more technical name for these things but they serve a useful purpose!

1300 miles on the bike now and I’m thinking of upgearing with a change of clutch by installing a 22 tooth cog Cosa clutch. Question is, will this go straight in or will I need to change the other cog on the christmas tree for something smaller. I could be wrong here but I think the original setup is 21/67-68 so want to achieve 22/67-68

Also, will any other modifications be required e.g. will the clutch cover from a 200 be required?

Tried to find the answer by going back through postings without luck.

Cheers, AK

Thanks, Curare. I’ll order one if these from SIP. I remember you recommending the 21/65 gearing for this kit before. 22/68 will save me splitting the cases. I don’t mind a bit of dremelling. Was thinking of ordering a Mazz race crank with the clutch but will install this later when I’ve clocked up a few thousand miles.


you should be able to fit a cosa clutch with no futher modification on a LML, but I say you should since I have worked just with two of them so if there are some small differences I cannot remember.
In any case even if you have to do some modification as it is necessary with some older crancases, these modifications are of minor entity and can be done with a dremmel in few min. even if you are not an expert dremmel user.

With a 22/68 you will have the same ratio that if you were using a 21/65.
This ratio is the longest ratio to use you with your Pinasco. Of course it will take you longer to get to 100kmh.