400-4 engine racing

[TOMMO.W]

Hi,
First ride out this year and the bike ran fine until 10 miles or so, then it felt as if the engine would not go back to tickover.
I am guessing that carbs are sticking perhaps due to getting hot.

Any suggestions of how to correct this?

Cheers Tom

[Johnwebley]

How high is it revving?

Does the 400 have push/pull cables?

It might have loosened up enabling the motor to spin more freely,

Or it could be an air leak in the induction area

Sent from my SM-A750FN using Tapatalk

[Nurse Julie]

How high is it revving?

Does the 400 have push/pull cables?

It might have loosened up enabling the motor to spin more freely,

Or it could be an air leak in the induction area

Sent from my SM-A750FN using Tapatalk

Yes John, push pull cables.
Could be throttle cable adjustment nut at the carb end has come loose or the cable may have slipped out of the main channel on the big butterfly thingy on the top of the carb and has the carbs wedged open. Heat not usually a factor. It's probably just a mechanical part slippage or failure. That's if the revs stay up high and don't fluctuate. If the revs fluctuate up and down, regardless of throttle position, it's more than likely an air leak.

[TOMMO.W]

Thanks for your suggestions. I bought the bike a short time ago so I am thinking that I will take the tank off and check carbs etc for any thing that doesnt seem correct.

Thanks Tom

[Lobo]

… if no luck check the advance / retard mechanism not sticking.