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General => Introductions => Topic started by: Ruban on Wednesday, 13 May 2026, 03:30 PM

Title: To much fuel?
Post by: Ruban on Wednesday, 13 May 2026, 03:30 PM
hi will see if i can explain in my bad english. i have a K7, 4000km.

it has started to run rough and smokes black smoke, it feels like it is getting too much fuel. i tried changing the map sensor but no difference anyone with the same problem?

 thanks in advance
Title: Re: To much fuel?
Post by: KiwiCol on Wednesday, 13 May 2026, 05:59 PM
Hi Ruban welcome to the forum, sorry you're having issues with your 14, the guys will be along shortly & may be able to assist you.   

I think a bit more detail / history on the bike & the issue would help in diagnosis.   Good luck.
Title: Re: To much fuel?
Post by: Mick_J on Wednesday, 13 May 2026, 06:26 PM
Welcome to the forum Ruban.  :onya: Does it start up easily and run fine until warm them stall and not tick over smoothly when you restart it?
Title: Re: To much fuel?
Post by: Eric GSX1400K3 on Wednesday, 13 May 2026, 09:54 PM
Welcome mate, 

A blocked low and high pressure fuel filter can also contribute to rough running, same as incorrectly balanced throttle bodies, tp and stp sensors, perished vacuum lines and dirty injectors. 

Also check the air filter and replace if dirty and check spark plugs.

Usually an introductory message at the right spot will help you get further responses, and perhaps some more detail about your bike and the issues you're having.
Title: Re: To much fuel?
Post by: Cikik on Thursday, 14 May 2026, 02:52 AM
Doesn't a faulty clutch switch result in rough/poor running??
Title: Re: To much fuel?
Post by: Hooli on Thursday, 14 May 2026, 07:02 AM
Only time I had black smoke was a blocked high pressure filter.

My assumption is the lower fuel pressure it caused resulted in a very poor spray pattern from the injectors and poor, incomplete combustion.
Title: Re: To much fuel?
Post by: Eric GSX1400K3 on Thursday, 14 May 2026, 10:42 AM
Yup, you need proper pressure behind the injector for a good spray pattern, a blocked hp filter limits the rail pressure too much.
Title: Re: To much fuel?
Post by: Ruban on Sunday, 17 May 2026, 05:45 PM
Thanks a lot !

I have been driven 1000 km this year without any problem , last trip the bike start go uneven. Ok to drive home but no power .
Next morning uneven idle and really black sparks and black smoke. Checked the filter , no issue

Not easy ;(
Title: Re: To much fuel?
Post by: Hooli on Sunday, 17 May 2026, 06:10 PM
Are all plugs equally black? Or does it look like only some cylinders affected?
As the HT leads do rot in the plug caps. Trimming 5mm off and screwing them back in can fix that.
Title: Re: To much fuel?
Post by: Eric GSX1400K3 on Monday, 18 May 2026, 11:43 AM
As said, check the in-tank  high pressure filter as well as the 'teabag' low pressure filter.

Detailed descriptions on here
Title: Re: To much fuel?
Post by: Ruban on Monday, 18 May 2026, 03:09 PM
* All plugs are black
* filter is checked and ok
Title: Re: To much fuel?
Post by: grog on Monday, 18 May 2026, 03:24 PM
Check oil temp switch resistance.@20c should be around 60K ohms. @80c-6K.
Title: Re: To much fuel?
Post by: KiwiCol on Monday, 18 May 2026, 03:36 PM
Good call Grog, if it thinks it's still cold it'll run on the starting mixture.
Title: Re: To much fuel?
Post by: Eric GSX1400K3 on Monday, 18 May 2026, 03:57 PM
As per post #4, a faulty clutch switch will run te bike in a default "get me home" fuel mapping.  Swit h is up at the clutch perch and audible click heard when you pull the clutch in.
Title: Re: To much fuel?
Post by: Hooli on Monday, 18 May 2026, 05:34 PM
Aye good suggestion Grog, I should have thought of that as I've maintained two bikes that have had the oil temp sensor go bad.
Title: Re: To much fuel?
Post by: VladTepes on Tuesday, 28 July 2026, 08:09 PM
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