Modern Vespa

Hello,

I have a vespa primavera 125 (2015). I bought it with 6k on the speedometer. I have done 3k and decided to do the service including the drive belt change on my own because I was losing top speed recently. I followed the typical procedure many videos show online such as the great video (I did not dis-assemble the clutch). I discovered the CVT installed was not the original, but it is not far off in structure from the original. The main difference is that the clutch bell does not have its spacer (the sits between it and the transmission case) attached to it rather separate.

I had a few issues in order:

1. The first time I re-assembled everything I put the clutch bell spacer before the clutch bell (between the CENTRIFUGAL CLUTCH GROUP and the clutch bell rather than after the clutch bell by mistake. I re-fitted everything and heard a click when I was tightening the outer nut on the drive pulley. This caused the wheel to be locked.

2. I re-opened everything and put the spacer in the right place and re-fitted everything as supposed to be. I hear a very clear loud friction noise by just moving the rear wheel myself coming from inside the transmission as if two metal parts are grinding against each other. This was not there before I did the service. I suspected the clutch but the shoes are not torn and the clutch bell seems fine. I suspected it is between the clutch bell and the case but I believe the spacer between them should prevent them touching. I took off the transmission case and moved the wheel, the noise disappears, but once I put back the case the noise comes back. The higher the speed goes the louder the noise becomes.

Does anyone have an idea what this issue might be?

Thank You!

Currently suspecting that the click I heard caused the clutch group nut has loosened as in here so will see if it is the case.

It did not turn out to be this. The nut is not loosened on mine so still troubleshooting what the issue is

You might have damaged a bearing in the clutch assembly.

Or the bearing on the case/cover?

Thanks, GTdespatchcourier and berto! This actually sounds very plausible, even though it did not come to mind first. My gut feeling is the bearing on the cover (and it is easier to do ) so I will try replacing this one first.

crankcase bearing change fixed it. Thanks!

Awesome that it's fixed!

Out of curiosity, do you mind clarifying which bearing you meant by "crankcase bearing"? The one on the crankcase cover?

Yes, the one on the crankcase cover: number 3 in the top photo, the one you suggested, berto

I am not sure I'd dare to start disassembling the parts in the second photo yet. However, now that this mission is done, I might become more courages in the future in case needed

Good stuff!

When you said "crankcase bearing", I was worried you had to go deeper in.

Thanks for clarifying, and I'm glad you are rolling again!