Poor idle..engine missing - new plugs too???

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fz14jp

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I have this little problem. My FZ1 was running rough, slight surging-like feel but after warm up at least idled somewhat OK. I then changed plugs (four new CR9E's)...there were 4 CR9EK's in the bike???? installed by previous owner. Anyway, now it won't idle hardly at all, surges up and down between 1000 and 1500 rpm at idle...very poor throttle response, almost dies if I don't ride the clutch to get going...seems to be a little better when I get to higher RPM's, but still runs like it is on 3 cylinders...not 4. The previous plugs looked like they may possibly be oil fouled....dark oily ring around the base of the plugs but electrodes looked fairly clean. I rechecked the wiring and they are all to the proper plug. Gapping rechecked and at 0.0028in (per spec's). I'm inclined to believe its either cylinder 2 or 3 (inside one(s) that is not firing properly since I pulled the wiring on 1 and 4 and the bike basically died at idle. Anyone ever have something like this occur with their FZ1? Should I readjust carbs?...if so, what's the best and easiest way to reset for proper mixture? Do wiring sets go on these models or coils? I'm not an electrician so I need some guidance from those in the know. Any help or suggestions is greatly appreciated. I love this bike and want to get it back out on the road ASAP!!!! Thanks for all the help everybody.
 
Those are the correct spark plugs for the bike.

Unless someone has been messing with the carbs there is no need to adjust the mixture screws. They have caps over them anyway that you have to remove in order to adjust the mixture screws.

Could be an air leak. Have you taken off the carbs? Make sure the clamps at the carb boots are all tightened and that none of them are split or something like that.

The coils could go, which would make the bike run on three cylinders. This would be most noticeable at idle. If you have access to a service manual there should be a procedure for checking the coils. Sorry I can't be of more help.
 
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Get an infra-red temperature gun and check the temperature of the exhaust headers. That should tell you which cylinder is mis-firing. Since the last thing you did was to change the plugs, I'd then check the connections for the plug. If it's still not idling smoothly with all cylinders firing, try sync'ing the carbs. That can make a big difference in idle and low speed smoothness.
 
Engine missing, new plugs??

Thanks guys. I'll recheck the connections to the plugs. By the way, the bike has only 3K miles on it and its a 2001!! Probably been sitting a lot which may also indicate a carb-related issue???? Anyway, I'll recheck everything and get back to you. I DO love this bike!!! Incredible!!!
 
fz14jp said:
Thanks guys. I'll recheck the connections to the plugs. By the way, the bike has only 3K miles on it and its a 2001!! Probably been sitting a lot which may also indicate a carb-related issue???? Anyway, I'll recheck everything and get back to you. I DO love this bike!!! Incredible!!!
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In light of this information it's probably not the coils or spark plugs. If the bike has sat for a long time then some of the jets and circuits in the carbs could be clogged. Have you opened up the carbs to clean them or at least verify that they are not dirty?
 
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