Mis-firing/ Stuttering at 6k rpm

[MrG650]

Hi guys.

After riding back home on weds nite and after a brief blast up to 120,i rolled off the power ,down into 4th for a 50mph speedcam, into 3rd and opened her up.As soon as i got to 6000rpm she started spluttering away,mis-firing and generally not being too chuffed with me in any gear.

Into the garage we went, out came the plugs.Didnt seem to be any sign of moisture but i gave them a good dry out anyway.Hairdryer down the chambers the lot. Took her out. . . no difference,back in, swapped the plugs round,still the same.

Heeeeeeeeeeelp!!!

[Spanner Man]

Good morning.

It would be well worth draining the carburettors, just in case some water has found it's way in.
Failing that it could be something in the ignition system that's breaking down when it gets to a certain load, check all connections on the coils etc.


Cheers

[MrG650]

Cheers,will try that. Update on the symptoms..

Its the back cylinder that is causing the problem.I disconnected the front spark plug and fired it up.Full throttle and it only revs to 6k rpm.Front cylinder is fine.

[cheungy]

May be off the subject, but can't seem to find where to post a new thread.. so have highjacked this one.

My SV650s K5 has been offroad in a garage for past 7 months.. when I took it out and ran it on the old fuel it ran fine for around 20km.. since then its starts to jerk and splutter at low revs...once upto speed and revs are over 6k.. its seems to run fine... Especially hard to take off, as when you engaged to clutch, it seems to find it hard to pull away.. so I have to be extra heavy on the throttle.

Since this started, I have filled up with new fuel, changed plugs, oil/filter, cleaned airfilter, and tried to run some redex injector cleaner (couldn't find any seafoam in Halfords). All have helped slightly, but bike is still running rough... Also did TPS Adjustment. although the line started moving up at 1700revs, so I didn't bothered making any adjustment, as didn't think this was too bad.. Also no dealer codes came up when I put it into dealer mode.

I'll given the bike a good thrashing now for about 100km, and things haven't really improved..

Does this point to blockages with fuel injectors? As when i went to dealer they said that this is what they thought was wrong with it, and they said that the dealers are the only ones who can rebalance the injectors. If it isn't definitely injectors, i would rather take it to my local garage...

Is there anything else anyone can think of that I can check? I have just got back into the country and am flat broke, so could do without having to put the bike into the garage.. although I am no mechanic genius...

Be greatful for any advice. Many thanks!!!

[tom-k6]

i had this problem a while back, it kept misfiring and cloncking out on me. turns out my immobilisor was fitted by a babboon with a screwdriver and some gaffer tape, and it was turning off my fuel pump mid-flow, and causing a really dodgy connection with it. i tried to re-wire it all but i got angry.....very angry and i now have a new shiny immobilisor/alarm fitted. fitted properly aswell, just a thought incase you guys have a datatool duo immobilisor.

[cheungy]

Heh, its not conking out, just the throttling isn't smooth and the bike stutters at low revs.. Haven't got a immoboliser.., so that shouldn't be the problem. but thanks for the post..