Revving kinda weird.

[esquire]

Whenever I rev my ZZR250 it seems to kind of slide down the revs (goes down gradually) instead of just dropping like it used to/should.

Can anyone suggest why this could be? I was thinking maybe the throttle sticking but I'm not sure.

[CitizenD]

Kwakas have inbuilt cruise control at both ends of the throttle cable. They stick all the time. A good place to start.

[Jonchilds]

If the throttle isn't sticking, it's probably a vacuum leak somewhere, or crap in your carbs preventing them from closing properly.

Sticking throttle is the most likely as the throttle cables NEVER get serviced, and slides in the carbs can get crap in them.

[CitizenD]

Jon's right. $8 can of carby clean and a $20 pack of bourbon and you're sweet.

[Tenchi]

If the throttle isn't sticking, it's probably a vacuum leak somewhere, or crap in your carbs preventing them from closing properly.

Sticking throttle is the most likely as the throttle cables NEVER get serviced, and slides in the carbs can get crap in them.

Mine was sticky, Derek took it off, gave it a bit of a clean, put it back on... top notch now. The revs were sliding down whenever I just let it go, but if I forced it back using my hand the revs would drop as you would expect them to.

Carby cleaner is cheap enough to give it a shot every now and then anyway.

EDIT: If you decide to take it off and put it back on again after cleaning, give it some corrosion protectant (WD-40) and run an oily finger along the inside ftw.

[esquire]

Mine was sticky, Derek took it off, gave it a bit of a clean, put it back on... top notch now. The revs were sliding down whenever I just let it go, but if I forced it back using my hand the revs would drop as you would expect them to.

Carby cleaner is cheap enough to give it a shot every now and then anyway.

EDIT: If you decide to take it off and put it back on again after cleaning, give it some corrosion protectant (WD-40) and run an oily finger along the inside ftw.

That's exactly what's happening with mine. Only forcing it back just speeds up the rev drop but doesn't put it all the way back to normal.

So clean the throttle cable + carby cleaner the go you reckon?

[Stephan]

That's exactly what's happening with mine. Only forcing it back just speeds up the rev drop but doesn't put it all the way back to normal.

So clean the throttle cable + carby cleaner the go you reckon?

Yes, it is...

[Dejavu]

Vacuum leaks are a common problem on the ZZR250.
The rubber inlets get old, cracked and also shrink so replace all 4 and should be sweet

[Jonchilds]

The only other thing it could be is that the idle isn't set entirely correct (when well and truly warm).

If the idle is set fine at cold, it will be too high on a carby'd bike when warm.