ZZR running bad
 

Mate of mine has a "p" reg ZZR600, every time he goes to ride it, gets 10 miles or so down the road n it starts misfiring......any ideas?

Cheers
Dan

Re: ZZR running bad
 

Got any more info? Does it seem like fuel or ignition? Are there any other features to the running of the bike that might be relevant?

Re: ZZR running bad
 

Bike was sat for 2 years, but then has been in use for past 8 months ish. Had carbs cleaned out when the restriction was put it and was running fine after that but then recently developed the misfire issue.
Bike has had a recent service, but i believe it may have been doing that before the service.

My thoughts where that may need a dyno set up due to its restriction? fuel air mix is wrong? Its restricted by washers so could that cause the issue?

Re: ZZR running bad
 

Unlikely to be restriction if it truly doesn't start running funny until ten miles are passed, it should be quite warm before that point so any mixture problems should be apparent earlier. Restriction with intake washers simply limits throttle area, so under the throttle level that the restriction describes no problems should be found.
Is it possible to determine whether only one or both cylinders are affected? And, if only one, which one?

Re: ZZR running bad
 

Sorry i ride FI so dont have any real knowledge of choke on bikes, but im guessing if that was still out it wouldnt have an affect on its running after its warmed?

Am unsure which of the cylinders are affected, but when have a chance can leave it running and try simulate riding to try and find the issue?

Re: ZZR running bad
 

Has he checked all of the idiot switches? my SV used to do that every now and again, and it turned out to be the side stand switch. Other one to check would be the clutch switch. It's unlikely but worth bypassing them just to check. They are weak points on 90's Kawasakis - I have a ZZR and a ZX7, both of which have suffered from problems due to crap switches.

My other thought would be a loose wire or corroded connector - both could cause an intermittent misfire.

Re: ZZR running bad
 

i'd have thought a stuck choke plunger would manifest itself earlier in the ride, but depends. If it starts to stink like unburnt fuel as it warms up then that could be a cause. will tend to idol too high though, unless someone has adjusted the idol to compensate already.

Re: ZZR running bad
 

Cheers for the ideas, will have a look over it n check it out.