Twitchy engine when cold (a bit more complicated problem) -
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post #1 of 3 (permalink) Old 04-02-2015, 09:48 AM Thread Starter
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Question Twitchy engine when cold (a bit more complicated problem)

Hey guys,

So when the bike is just started and say you are in first then you change to second (not much throttle), low revs (<7K) and then you slowly start to accelerate the engine will start "coughing" in a way. It is like the clutch engages and disengages very fast for say 1 or 2 or 3 times.

Then you back off with the throttle and then after short time it will do the same thing from say 2nd to third at say 11K rpm. In other words when you are accelerating and the bike is relatively cold it will start doing it.

This never has happened before in the 3 years I have the bike. And the outside temperature is relatively mild 16C, it isn't really cold or anything.

Moreover this started to happen even when the engine should be warm (after say 10 min). Gently cruising in 6th and then I can feel this happening once, then say 5 seconds later again.

After 30 min of relatively aggressive riding this doesn't happen, but still, I'm quite unnerved by it and completely destroys my confidence because if this happens in a curve I could crash easily.

I do have a quickshifter and I'm not sure if it has something to do with it. I've triple checked all the sensor/shifting rod, wires etc, but seems completely fine. My reasoning is that if it is a QS issue, this should happen all the time, bike being cold or warm no difference.

My suspicion are the spark plugs, as I'm not sure when they were changed (they were not in the last year and a half thats for sure). I'm going to override the QS and see if that helps though.

If you have any ideas, please feel free to share.

Thanks a lot!
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post #2 of 3 (permalink) Old 04-02-2015, 03:13 PM Thread Starter
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Ok, I've isolated the problem. I've bridged the QS so the problem didn't happen at all. I'm not sure why there is a problem with the QS, but I'll work from there.
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post #3 of 3 (permalink) Old 04-03-2015, 04:41 AM
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A fellow member experienced running problems which were eventually attributed to the QS.

Might be worth a read?

Best of luck, sorry I can't be more help but your post jogged my memory of this older problem.

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