Read The Manual

Thanks to the availability of the workshop manual for my bike on the site here I was saved a bit of to-ing and fro-ing with my local dealer. The temp gauge (it's a K3) had started behaving oddly - reading >60C when switching on, on a cold morning. Also occasional trouble starting from cold. Not too hard to figure out that as the ECT sensor supplies both the data for the temp gauge and enables the ECM to enrich the mixture when the engine is cold, that said sensor or its wiring may be faulty.

So when the bike is having a ride-in ride-out pre-service check this problem is investgated. After about 20 minutes the service manger tells me 'we've run it till the temerature is 110 and the fan comes on so the sensor is OK'.

So I tells him, I says 'look the fan circuit and the ECT sensor are nothing to do with each other'. Bloke looks quizzical, goes of for a further conference with chief mechanic and after a short consultation they agree that further investigation might be good. Bike is now serviced and a new sensor on order, should be sorted next week.

The lesson? Read the manual and try to understand as much as you can about how your bike works. Even good mechanics are not omniscient and can make elementary errors sometimes. If I hadn't taken an interest in finding out how it all works I am sure the problem would have been diagnosed eventually, but it would have taken maybe a week or two rather than less than an hour.

RTFM comrades. You know it makes sense.