Still no joy with the resistor.

Would it be anything to do with the 3tj clocks that i've patched into the cat loom? The tacho does work, registers the rpm as i rev the bike but still keeps cycling to 8k every few seconds.

How aboout this as an idea, could i take the feed from an HT lead instead of the ecu?

Wasn't there two things different in the loom ???
I thought the other was the throttle position sensor on the carbs .... ?

Err.......

Hmmm......

I do have the tps all connected up and as far as i know its working ok. I remember seing somewhere that if the tps is faulty the tach sweeps to 3 or 3.5k

I'm tempted to ditch the 3tj tacho and go for an aftermarket jobbie, either a traditional style tacho like the elliot/spa/scitsu etc... or something funky like the vapor gauges.

check the bulb on the dash,if it's blown it will give the same symptoms.

nick wrote:...or something funky like the vapor gauges.

Don't get a Vapor, they're useless for anything other than a speedo. The tacho is really unstable (on my TRX and the 400 I had a while back). An analogue tacho is loads better than a digital one

Some of the Bimota clocks break very easily and of course can't be replaced, they use Koso clocks

Went for a scitsu in the end, reasonable price and dead easy to fit