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I have a 1991 FZR600, after I start my engine, the idle would drop to about 900 then the idle seem to go up and down like the RPM meter is shaking. The engine seems to swing the idle speed up and down, then after a few minutes it will eventually stall. What RPM is the engine suppose to idle at anyways?

When I try to drive after few minutes, the bike feels like the gas line is "choked". I pull the gas lever, the engine dont seem to respond, then the RPM will eventually drop slowly all the down to ZERO.

What can I try to do to the bike that can make the problem go away????

PLEASE HELP ME! HELP WOULD BE HIGHLY APPREICATED!!! THANK YOU

Im not getting any replys, please reply!

My bike is messed up and getting really mad, and would appreicate some help.

THANK YOU VERY MUCH!

usual formula = check if your carbs are clean. 900 is a little low for a sportbike. The recommended Idle for even my xs400 is 1000-1200 rpm. Sounds like a carb problem. spray a little starter fluid through the carb intakes and see if that cleans things up a bit. If not you will need to take them apart and clean out the gunk.

Before that check to see if your gas line is OK. Detach the feed line from the carbs, and see if gas flows freely in the prime (PRI) position, and then when you crank your starter, gas should flow again in the on/reserve position.

IHMJack wrote: When I try to drive after few minutes, the bike feels like the gas line is "choked". I pull the gas lever, the engine dont seem to respond, then the RPM will eventually drop slowly all the down to ZERO.

fluctuating Idle usually means a rich condition. If by "Fuel Lever" you mean the choke, then the bike probably is rich, if it dies -When the bike is COLD- If the bike is dying when you pull the choke -When the bike is HOT- that's probably normal.

kar_the_terrible wrote:usual formula = check if your carbs are clean. 900 is a little low for a sportbike. The recommended Idle for even my xs400 is 1000-1200 rpm. Sounds like a carb problem. spray a little starter fluid through the carb intakes and see if that cleans things up a bit. If not you will need to take them apart and clean out the gunk.

Before that check to see if your gas line is OK. Detach the feed line from the carbs, and see if gas flows freely in the prime (PRI) position, and then when you crank your starter, gas should flow again in the on/reserve position.

Before my friend sold me the bike they told me they clean the carb already I hope they did a good job at it.

TechBMW wrote:

IHMJack wrote: When I try to drive after few minutes, the bike feels like the gas line is "choked". I pull the gas lever, the engine dont seem to respond, then the RPM will eventually drop slowly all the down to ZERO.

fluctuating Idle usually means a rich condition. If by "Fuel Lever" you mean the choke, then the bike probably is rich, if it dies -When the bike is COLD- If the bike is dying when you pull the choke -When the bike is HOT- that's probably normal.

So how in the world do you fix the "RICH" problem?

I had the same problem

ended up being a fuel line problem, the old hoses were brittle and develope a crack = no vacuum. replaced the hoses and voila. $3 fix.

I will try to work on the bike again when I have time.

Sounds like your Idle jet or Low speed jet is dirty.

You really didn't say how the throttle response was.

Does it bog or pop when you whack it during the low RPMs?

I would never trust when some one says they cleaned the carbs when the bike acts as if it has a fuel problem.

I have more customers that bring their bike in that say "its not the carbs I cleaned them already"

Sure enough I tear in to the carbs and the jets have dirt or some other crap in them.

Not to mention I my self have broken carbs down that looked as though they where half way decent and just gave them a quick spray of cleaner.

To only be banging my head later when I can't get them to Sync right.

1-Remove the carbs
2-Tear them apart
3-soak all parts in a cleaner of choice
4-Blow compressed air through all parts both ways.
5-reassemble the carbs and set to factory specs.
6-Tune or synchronize the carbs

Doing it right once makes for a lot less headaches latter.

Good Luck!

Mike

You guys have anymore advice for me? I still cant get the bike to run correctly

Help would be appreicated