Author Topic: smokey #4 pot.  (Read 2467 times)

petercb750

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smokey #4 pot.
« on: November 26, 2005, 10:28:53 PM »
My recently rebuilt (not by me) K2 motor gets very smokey from #4 exhaust when hot. Doesn't smell totally oily, but more like a rich mixture smell but with a fine blue smoke. My thoughts were if it is mixture smoke it would be black?
Fine on start up, and warm up, but after a couple of miles it smokes like hell (under power and at idle). Checked all plugs (put a new set in to test), and #4 very carboned and a bit wet (after about 1 mile!), #3 a bit the same but not as bad, and the other 2 ok.
Have had suggestions from valve guides to rings, as well as carbie set up. Any thoughts?

Offline SteveD CB500K0

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Re:smokey #4 pot.
« Reply #1 on: November 27, 2005, 06:16:55 PM »
In general,

White smoke is moisture (when cold)
Black smoke is running rich
Blue smoke is oil

If you are burning oil it's either coming past the rings or past the valve guides.

I'd run a compression test, if #4 is low put a bit of oil down the plug hole and try again. If compression is now good, then you have a stuck (or broken) ring.
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jimshea

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Re:smokey #4 pot.
« Reply #2 on: November 28, 2005, 10:32:31 AM »
Peter,
Are you located in the UK? Steve and I are in the south, near Bracknell/Reading.
Cheers,
Jim.

petercb750

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Re:smokey #4 pot.
« Reply #3 on: November 28, 2005, 09:03:50 PM »
Jim/Steve - I'm in Tasmania! Since the posting I have decided to take it in for complete carbie balance, tune, compression test etc, and try to eliminate other possible causes before going the full monte - but it might be a case of wishful thinking!! I wish I'd listened to my dad as a kid and done a trade - like motor mechanics!! :-)
Do you think the lack of smoke when cold is just an indication of the oil being thicker and therefore not getting past ring/guide?? Or possibly carbie not flooding (I turn the fuel off in garage) until run for a bit?? I have been told that flooding could lead to some oily smoke, and as I said it does smell very rich with just a hint of oil/blue and idles rough.
On a brighter note, I've also just purchased a nice little 400/4 that originated in UK for the wife to use - great little bike!
Thanks for your interest and responses - will let you know the outcome.
Have attached pic of the toys in the spare room downstairs. Very spoilt!
Cheers
Peter.
PS weather better here than where you are at present!!

 

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