Rough idle and jerking under 4k rpm

sannick

New Member
Hello

I bought a FZ1N from 2008 a little over a year ago now and its bin riding like a dream until now. Part of the deal for me to buy the bike was that the rotor would be changed to the new on ( witch i was told is actually a redesigned old genI are old R1 rotor can't remember what the guy said ).

mods
Akra slip on
bigger sprocket in the rear and a speedohealer
All around new led lights
oil temp gauge
( thanks previous owner )
and heated grips from oxford

The 1st time i had the problem i was at a red light and my idle rpm started dipping from about 1100 to 800. As light turned green i left but leaving was like the bike was in 2nd or 3rd and you release the clutch fully without giving it much gas ( jerky and no power ) once above 4k or 5k everything was normal. Next red light same thing.

A few days later ( and some research ) i pulled my ignition coils and measured them and all where in spec and the same primary and secondary. So i put them back and same problem. A few days later i pulled them again ( maybe i missed something ) measured again all still the same so i put them back. And the rough idle and jerkyness was no more.

A month are so later ( about 600km) the problem was back. I started the bike let it idle for 20 mins to be sure the problem was there ( and it was ), let it cool down to where i could touch it pulled the ignition coils measured them ( all the same in spec ) i even heated them to where i could barely touch them and the all stayed the same. Put them back, started the bike, let it idle for 30 mins and no more problem.

So i found out that it only occurs only but not always when the oil is warm ( about 60c ) if the bike is at 103c and the oil is still at 20c or 40c there is no problem.
When i pull the coils and put them back the problem is gonna for a while. And the coils look fine as do the connectors.
1st the idle starts dropping from 1100 to 800 and when you leave the bike running the idle goes more and more to the 800rpm to where it occasionally jumps to 1100rpm.
The check engine light isn't on and there is no code not even in di mode.

Anyone any ideas?

Here is a clip of it where its having its bad temper
 
Hello,
My battery is only 9 months old ( because the last one was still the original from 2008 and was done ) and just to make sure i just measured it. It had 12,74V.
Its a VMF AGM battery A CTZ14-S it has 11.2Ah.
 
Well I do only have a first gen so I don't know much about the second gen but I think it might be the injectors then I was also asking about the battery because I don't think the alternator kicks in till 4k
 
In di mode you can test them 1 by 1 and the injectors all sounded the same to me. And i'm not sure but if a injectors are a spark plug bad isn't it hard to start when its cold?
A few days ago i did put some injector cleaner in in the tank ( problem wasn't there and didn't happen after )because i was thinking the same thing.

Ps i think you are right about the alternator i does start fully charging around about 4k
 
Did you ever solve this? Mine is acting the same currently
Ive had this problem twice now. Try putting new plugs in it before you go the coil route(do test the coils tho). My problem was plugs. I guess they are serious about that 8k mile interval. Mine started acting up at 26k on the plugs. I was an idiot to think they last that long on a high compression engine. To be clear I also replaced all the coils because I was in there anyway and I had the money. But they were all testing correct. Let us know how it goes.
 
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