Speedo drive issue

[Spuddyd]

Hi Guys

I’m about to pick my new baby up on Saturday, a 1996 UK bike. The owner has stated that there is an issue with the speedo/drive and for what I can make out, it’s a common issue.

Can someone throw some light on what the issue might be?

I plan on swapping the clocks out for a digital set-up at some point but would rather not have to do that straight off the bat.

That leads me to my next question. Would you go Acewell or Koso?

[Tarwetijger]

The drive unit (gear unit assy as Yamaha calls it) seized up (11 in the pic) or the tabs of the retainer could be bent (5).

[Bucko]

Hello, I had a problem where the speedo needle would flicker intermittently before it died completely, turned out it the drive plate lugs were worn/ bent. I bent them back and it worked fine for a while then failed again so I bought a new one for around £10 I think, that's fixed it.

[Spuddyd]

Update:
Found the tabs on the drive plate and checked the gear drive to find it a “bit stiff”. Cleaned it out and regressed it, put a new drive plate in and it worked , for about 10 miles............
Pulled the front wheel only to find the tabs bent again. Checked the gear drive to find it works going forward but is seized when you try and rotate it backwards!!
New gear drive and a second drive plate fitted and we are good to go.

MOT passed and now onto the carbs as she is running SO rich, the exhaust cans are jet black inside but that’s a whole new thread.