yamaha fzr400 running problem ?

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yamaha fzr400 running problem ?

hi guys fairly new to visordown but im need of your help, I recently brought a yamaha fzr400 1wg model as a bit of a project to restore but ive been having a problem with it recently, the problem is now and then it will die on me ? so i pull over put it in neuteral hit the starter button and then it will start sraight up again ? HELP .

Your description is a little brief. Perhpas a bit more info may help to form a possible diagnosis. However assuming it dies out rather than abrubtly cuts out it would be a fuel problem first port of call would be the fuel tank breather. Second would be the fuel system including the pump. I have kept my diagnosis effort brief inkeeping with the original question.  

Id say that it dies out rather quickly usualy when de-accelerating and also then it sometimes does it when accelerating and then will only start up once ive pulled over and stopped and selected neauteral.

Just a thought. Does your engine cut out if the side stand is down. Could be a loose relay or side stand spring tripping it out when you de-accelerate. Otherwise I'd agree withMac-Cecht and be tempted to look for a fuel problem.

No, because it doesnt have one lol someone at work asked me that as well

Well, just 'cos it doesn't have one doesn't mean that some of the wiring ain't dodgy..Still, what we need to know first is whether it feels like an ignition problem or fuelling.If it's ignition, then you'll be riding along and it'll either just die, or it'll start mis-firing so that it judders and jerks badly, then dies.If it's fuel starvation then it'll suddenly sound a bit flat and farty, lose power and cut out. If it was any other fuelling problem it *probably* wouldn't be intermittent.How often does it do it? You say it's usually on deceleration, sometimes on acceleration. Ever on constant throttle? Ever on the brakes?

On a few occasions it has backfired and then died out but mostly it will go flat and farty like you say Tappy, it has happened on constant throttle and under heavy braking also.

Does sound like a fuelling problem then - back-firing could be over-fuelling (float valves sticking shut) or under-fuellin (float valves weren't shutting off properly) both due to dirt but would be a bit odd to see this on all 4 carbs at the same time such that the bike cuts out. If it's been siting around for a while then my guess is rust in the petrol tank clogging up the fuel filters, pump and float valves.Take the fuel lines off the tank to look for traces of rust. Try fitting an in-line fuel filter - it won't cure the problem but will help show if there's rust coming out of the tank.Or take the master tap off the tank (often tricky) and check the filters in there.Or take the tank off, and empty it out into a couple of petrol cans thru' a filter and see if there's rust / debris in there. If you reckon there's rust in there then you can use various systems to prevent it eating right through or continuing to clog your fuel system. Go to www.frost.co.uk and look for the motorcycle tank repair kit (used this on an old XJ900 tank recently and it seems much better than the Petseal I used years ago).If it is a rust problem then clean the filters, fit an inline filter, and you'll also need to clean out the carbs etc.. 

hi i have the exact same problem with my 1wg i have to keep replacing plugs over fueling i had a gsxr 400 before that did the exact same thing on acceleration it would jerk as if there is no fuel and then it would cut out after a while where i had to allow the bike to stand for a few minutes i replaced the filters and had my carbs synced rode like a dream afterwards.

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