throttle stuck?

[T180985]

im pretty sure my throttle is stuck open as my zxr400 keeps revving to 10,000rpm and staying there by itself but it i push the throttle the wrong way as hard as i can it stops it doing it, this makes riding very difficult as you can imaging. how easy is this to fix? any suggestions i really need to get it sorted tonite

[RedexRobB]

That is rather odd! Is the throttle cable properly adjusted? There should a roughly 3mm play in the throttle before it starts to open the carbs up.

Could also be some dirt in the carbs.

[T180985]

had a chat with a guy at work who had a look at it for me, he said its probably the throttle return as the throttle isnt snapping back as its supposed to do. going to take a look at lunch, anyone got any idea how to adjust this?

[RedexRobB]

Well theres two seperate cables, one for opening and one for closing. The latter being the 'return' cable. The manual should show you exactly how to adjust them but the gist is there are adjusters a few inches down the throttle cable, one for opening cable and one for closing. Youll need two 8mm spanners iirc.

The way i would do it is slacken them right off so theres loads of play on the throttle, roll the throttle tube forward till it stops and adjust the opening cable till theres 3or4mm play from the stop to it starting to open the carbs. Then adjust the return cable till it just about starts to pull the throttle tube off the stop. Id also run some oil down the cables if you have time to take the switchgear apart and if you can, also work some oil into the throttle return springs on the carbs. Youll need to take the tank and airbox off to do this, but will ensure that everything that needs lubricating, has been. You should have a nice silky smooth throttle after that!

[masterofinsanity]

have you adjusted the tickover? messed with the carbs? and not set the tickover screw back properly?

[T180985]

ok its now fixed and works slightly better than when i bought the bike, not sure what was done to fix it as we did alot of different things including getting through half a can of wd40 lol there was a bit of dirt under the throttle so cleaned that up and reattached all the cables again which seems to have cleared up the problem for now bike was alot easier to take apart that i thought

oh another quick question.... whilst looking at the airbox it really didnt seem to be that great design, is it restrictive? or am i just used to seeing massive air boxs in cars. If restrictive is there much i can do another this? doesnt seem to be a huge amount of clearance underthere