Thumper Club Forum

Technical => Bike Problems/Questions => Topic started by: xbally on March 06, 2021, 02:22:03 PM

Title: NOISY RS250 TACHO GEAR
Post by: xbally on March 06, 2021, 02:22:03 PM

Not come across this before .The tachometer drive gear on my RS 250 is extremely noisy -to the extent I thought there was a serious engine problem but upon checking it's definitely coming from the tach head. Just wondered if anyone has any idea of what it might be before I investigate further?

Title: Re: NOISY RS250 TACHO GEAR
Post by: tevie54 on March 09, 2021, 12:12:35 PM

Are you talking about the little cam gear drive on the side of the head? There is a bearing inside but apart from that there's not a lot to go wrong in there.

Title: Re: NOISY RS250 TACHO GEAR
Post by: xbally on March 09, 2021, 01:04:29 PM

The noise seems to emanate from the tacho instrument head rather than the engine as far as I can tell.

Title: Re: NOISY RS250 TACHO GEAR
Post by: tevie54 on March 09, 2021, 02:43:55 PM

Well the good thing about RS's is the clocks do come apart so you can strip them down and have a good look. I've just taken some XL250 clocks apart but they're glued together so you have to use a dremel to separate the two halves to get to the speedo mechanism.

Title: Re: NOISY RS250 TACHO GEAR
Post by: xbally on March 09, 2021, 03:47:01 PM

Yes I have a spare set but they have no pointers on the dial and I'm wondering if I can swap the ones off my existing clocks on to these.

Title: Re: NOISY RS250 TACHO GEAR
Post by: tevie54 on March 10, 2021, 10:11:56 AM

You should be able to but they are quite delicate, I think the needles are glued to the shafts so you have to prise them off carefully