Starts fine, cuts out once revved

[bibby]

Just bought a zxr400 l9 it starts great and rides but if you pull the throttle back quickly it cuts out, balanced the carbs and its still happening? Any ideas? Going to balance carbs again tomorrow thanks again

[CaNsA]

Air/fuel mixture might be off.
Sounds like flooding to me mate.

[bibby]

How do i adjust that mate

[Tirpitz]

Save your time rebalancing the carbs. If you'd fecked that up it would be a pig to start. You say it starts well so you've done it right first time. When you start it from cold does it tick over without choke well above 1000rpm? Mostly from cold it will lump about around the 1000rpm mark on the point of stalling. You need to hold the throttle slightly open to move up to a smoother tickover. So if yours is ticking over faster from cold it suggests it is running rich, as CaNsA suggests. Sorting that out requires carb expertise as someone might have mucked with the standard jetting.

Check the choke cable adjustment too to ensure the choke is not stuck on. That would cause rich running. If you're going to get access to the carbs again check the choke mechanism on the carbs to ensure it isn't sticking the choke on.

[bibby]

Just rebalanced carbs again running alot beter, what should it be tickin over when its warm? Made up how its running atm now still a tiny bit of stutter when the throttle is turnedbut nothing like last time

[RedexRobB]

Are you balancing the engine when its warm? its needs to be fully warmed up when you do it.

[bibby]

Yep, let it run for a while before i balanced it, what should it rev at as im used to cars lol

[RedexRobB]

Tickover should be fine, which by the book is 1200rpm(?), but I know some people balance them with the engine sat at 3k, then readjust to 1200.

[bibby]

Thanks mate ill keep this in mind

[bibby]

re balanced them once again as when i started the bike up it wouldnt rev past 4k? so re balanced the carbs and still wont run above 4k? sounds to rich? what else could this issue be? should i just put it into a garage to get it sorted?

[CaNsA]

yeppers.

[bibby]

are the butterflys ament to be closed on idle?

[RedexRobB]

Near as closed but they aren't, otherwise the bike would stop.