Wont start run when warm?!?

[splinter696]

Hi All...

Just brought a 1990 zxr400, i cant wait to get her on the road (DAS starts next monday... yay!) But i seem to be having a few problems.

When i brought it, it had been sitting in a dark, dingy, spider-filled shed for about three years, managed to get her to limp home after jumping her off my van, it would cut out under about 3500 rpm, but ran sweet over 4k.

I assumed that this was due to dirty pilot jets, so stripped the carbs and gave them a clean, the pilots were not too bad, but the main jets had a little toad in. I have literaly just put the carbs back on, and fired her up, I let her idol for 15 mins, and although she was hunting slightly, she stayed ticking over. After 15 mins, she cut out, and hasnt ran for more than a couple of seconds since...

... i dont know what else to try!

The fuel pump, doesnt seem to click when you switch the ignition on, but as it runs fine over 4k, i assume it works.

Also, my main jets are 102, what is the standard mixture for these?

Any ideas/thoughts woyuld be greatfuly recieved...

[techie]

Ok probably the next thing to check is the fuel filter for bloackages or rust in the tank getting in and blocking off the jets again. Fuel pump ONLY runs when the engine is turning over. Disconnect the feed to the carbs and direct it into a catch container and try to start the bike. Fuel should come out at a good rate. You may have even got an air lock in the fuel line, purging it by the method described to check the pump will work for that too!.

Main jet sizes are usually 95 to 105.

[zimm]

sounds like its running rich, my H1 was 4 turns out on the mixture when i got it and wouldnt start on the button at all once warmed up.. would start if bumped, but wouldnt idle.

[ratbag56]

hav u checked the valve clearances this causes poor starting when cold? mite be that?