TS125 rev counter problem

[rossco]

Hi, I’ve got a TS125 with an intermittent rev counter problem. It seems to work ok until the bike is warmed up and then it starts to rattle badly as if the drive gear for the tacho is not quite engaging properly. The rev counter dial then goes back to zero. It’s a bit of a pain to remove the whole tacho drive because it looks like I would need to remove the whole clutch and primary drive. I was wondering if anyone had seen this issue and had an easier solution please?
Thanks

[DAVID THOMPSON]

broken drive cable ???

[rossco]

Thanks but I wish it was that simple. Cable and drive on top of crankcase are fine. The drive inside the crankcase appears to be a worm gear driven by a round cog sitting behind the clutch basket that moves in and out to engage. It looks and sounds like, when hot, this cog moves out and stops aligning with the worm gear. Probably not too hard to fix if it didn’t involve taking off the whole clutch and primary drive. Any shortcuts would be really welcome.

[Gerryman Ts125]

Your problem is more complicated than mine. I had a strange reading rev counter. I checked the drive on the main cases, it worked great
Then the cable, it was turning fine too. But once I took off the tach and shook it. The metal little end of bit of both bulbs fell out the hole they fitted into. The glass part were smaller and one or both of them, stopped it working. Hope you find a cure for your errant one