rev counter

[jackson98]

does anyone know why the rev counter rises and falls while the bike is running without revving the bike

[raesewell]

We will need a lot more information to give you a considered response. Knowing which bike as a first step would help.

[Guest Richzx6r]

From that description it sounds like hunting

[fastbob]

Rises and falls how much ? If it's a gentle fluctuation you should be able to relate it to what you can hear . As previously mentioned this is called Hunting and it occurs when the carburettor is not quite at optimum tune . If the rev counter is shooting up to indicate high revs without any noticeable change in engine note then who knows . As previously mentioned , it might be a good idea to tell us what bike this is .

[raesewell]

Without knowing what bike we are talking about we don't know if it's carburettor or injection.

[fastbob]

does anyone know why the rev counter rises and falls while the bike is running without revving the bike

 

Is this even a question about your actual bike or are you merely curious ?

[raesewell]

It looks like we can put this down as a post and run Unless they are at work.

[jackson98]

its a yamaha YZF 600 Thundercat aero supersport and has been sat for a few years

[Mr Fro]

its a yamaha YZF 600 Thundercat aero supersport and has been sat for a few years

 

Any chance of a vid mate?

[raesewell]

If it's been standing a while it could be stale petrol.

[Guest Richzx6r]

My dad has a thundercat have you or previous owner changed the exhaust system/end can by any chance if so it will need fettling with regards to fuel mixture

[jackson98]

My dad has a thundercat have you or previous owner changed the exhaust system/end can by any chance if so it will need fettling with regards to fuel mixture

 

ill look into it, thank you

[Guest Swagman]

You say it has been stood a long time, then I would suggest you have the carbs cleaned sounds like idle jets are clogged, ultrasonic would be best.