ZX400G starting problem

[quaidpinder]

Hello everyone uncovered the bike last week and tried to start it after being stood for a couple of months , it turned over ok but didnt seem to want to fire up , after some time of trying the battery died , i could hear it trying to fire but it just wouldnt go . i recharged the battery and tried again, this time it did run with full choke but only 2 cylinders then after a couple of minutes the other 2 cylinder came into life i switched it off and left it for a few minutes and tried again but this time it just turned over and back fired like a shotgun going off !! . I am assume it would be caused by bad fuel in the carbs or faulty or fouled plugs or a knackered cdi . i have removed the carbs and plugs and intend to give them a bloody good clean . the battery is on charge so hopefully this should sort it , anyone had a simular experiances ?

[RedexRobB]

Since it ran id say the CDI is fine and that cleaning the plugs and carbs is the best thing to do. I reckon just a clean of the plugs will do it as sounds like youve only flooded it with it backfiring.

You might find the carbs gummed up were the fuel has gone stale, good bit of carb cleaner and agitation with a paint brush should see them nice n clean. Clean the plugs up with a wire brush and reset the gaps. When you come to start it might take a bit of trying where the carbs fill up but should fire eventually.

[quaidpinder]

Well tonight ive had the carbs apart n cleaned them and put them back together and its no bloody different although i did notice that the rubber diaphrams inside the carb are a sod to get back in properly they seem almost oversized , possible they have been changed for ones that are the wrong size previous ? as most of the screws are a bit mangled so they have been apart a few times before . i try to push the outer lip into the carb surround then pop the plastic cover over and do up the four screws but every time i get them in when resealing the cover it seems to pinch the bellow bloody iratating .. anyhow got i back together something like it and there is still no action from the engine so next im gonna try some new plugs and see what happens..

you can see the rubber bellows not inserted properly got to try again to put them back proper

[masterofinsanity]

get that battery fully charged and put a new set of plugs in and i'm sure it'll be sorted!

[quaidpinder]

yep you were right on the money ,charged the battery, cleaned up the plugs and she started no problem. it does however seem to be over fueling as when i give it some it splutters and struggles to rev at all but if im gentle with the throttle it revs all the way through the rev range confused ??!! maybe the carb balance will sort this ?

[lewisdale]

or possibly a air leak on the inlet rubbers?

[quaidpinder]

could be ! although i did check over these and they looked fairly clean ......?!

[lewisdale]

get some carb cleaner,get the bike started, and put youre fuel pipes into a can of petrol so you can take the tank off if you understand what i mean then spray the carb cleaner all around the rubbers, if there is a leak you should be able to notice a difference in the running of the bike as you do this

[quaidpinder]

ok thanks will give it a try and see what happens still got the bike pulled apart so it will be a 5 min job ...