fazer 600 1998 running problems

[marty3000]

Hi I have a brain teaser, my Fazer starts fine, runs fine for a few miles then starts to play up. Especially in and around town with stop start traffic. If on the open road and I keep the revs up high no problems. At low speeds and low revs problems start. When I open the throttle to overtake the bike dies and then surges forward with excess power because I have to open throttle that extra bit to overtake.  Then at high revs bike runs fine, for while then the cycle starts again....???

I have also noticed that my full gauge has a life of its own, riding along now and again my gauge will go to full (when I have between 1/4 and 1/2 a tank of fuel), and problems as above appear worse than usual. The needle on the gauge will read what it wants when it wants and then return to 'normal' reading.The above symptoms get a little better but do not improve completely???

Any suggestions greatly appreciated.

[Dead Eye]

Sounds to me like an air / fuel mixture problem? Or maybe even an intermittent cylinder?

First couple of things to check is the air filter and spark plugs. Go for a bit of a ride, come back and leave the bike running for a few mins. Then remove the spark plugs (be careful, the engine will be hot) and check if they are clean or sooty. This will tell you if the bike is overfuelling.

Whilst the engine is hot, use a bit of water and squirt it on each of the downpipes. Obviously dont touch because again they are very hot - if the water doesnt sizzle then one of the cylinders isnt firing properly.

Do you have any idea roughly what sort of MPG you get?

This is just a couple of basic bits and pieces ive picked up, no doubt someone will be along shortly with other ideas

Also, if its running rough at low revs it could just need the carbs balanced. Do those quick checks first as they arent going to cost you anything apart from a bit of fuel

[marty3000]

Thanks Dead Eye will try your suggestions and see what happens

[CRH]

sounds like fuel starvation? chk your fuel filter? also make sure your choke is coming off!

[CRH]

if what you says right? runs fine first off when cold?? then it could be the choke sticking on !! strangling the motor when wamed up?? chk it at carb end? clive.

[red98]

yes as above....carbs,filter and also check the tank ,cleaning and flushing  might help you could also check the fuel guage float at the same time it might be sticking and affecting the guage 

[Gnasher]

Check the tank breather tube (under the tank) isn't partly kinked/twisted very common this on the pre 00 models.