bad plug? or something else?
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- Settled in member
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bad plug? or something else?
So my bike's been running Ok lately... but today after a short ride my bike started to miss-fire but erratically. Like it was running outta fuel, only it wasn't... sounds like it's running on 3 cylinders and can smell the fuel when idling... also backfired a bit while idling.
So, I'm thinking it's probably a bad plug? But will a bad plug miss-fire erratically though?(like idle fine then splutter splutter, cough, coke, splutter splutter
) Or could it be something else? I'm guessing it's electrical of some sort and not a dirty carb which is what I thought before the smell of fuel and backfire while idling...
Any suggestions?
So, I'm thinking it's probably a bad plug? But will a bad plug miss-fire erratically though?(like idle fine then splutter splutter, cough, coke, splutter splutter

Any suggestions?
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Re: bad plug? or something else?
im sure someone will correct me if im wrong, but it sounds like plugs, if you start the bike then touch the exhaust pipes one by one, if one is cold then thats the plug with the problem, i had the same problem last year and it was the r/h rear plug at fault started ok but ran like a bag of #####, i know its expesive per plug but get all 4 changed and it should be fine.
- skinnydog0_0
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Re: bad plug? or something else?

I had a similar issue with mu nc30 years ago. It was a dirty air filter, when did you last change yours? have you done anything to the exhaust/carbs since you have had this happen?
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Re: bad plug? or something else?
I've changed my air filter about 15k last...I usually just blow the air filter out with compressed air... I'm pretty sure it's just a plug. I'll dig out some old but 'good' plugs to test it before I buy new ones...skinnydog0_0 wrote:on the plugs or;
I had a similar issue with mu nc30 years ago. It was a dirty air filter, when did you last change yours? have you done anything to the exhaust/carbs since you have had this happen?
- superlite
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Re: bad plug? or something else?
I'm tipping fried reg/rect or old fuel tap vacuum hose.
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Re: bad plug? or something else?
Nope Reg/Rec is fine (i have a R6 reg/Rec), fuel tap Vacuum hose will usually cause a problem under load or when revving high because the walls cave in if it's bad...superlite wrote:I'm tipping fried reg/rect or old fuel tap vacuum hose.
The problem was just a bad plug.... so it seems sorted now...
