I was told by a few people at today's trackday that there was blue-ish smoke coming out from my exhaust can on downshifts and closed throttle.
so yea i'm engine breaking on downshifts, so when I have the RPMs high and close the throttle, the revs drop and the smoke comes out.
I have not idea what this could be... can someone help me as where to start??? next trackdays are in less than a month!
background is:
bike was crashed last september.
sat in a garage until about a week ago, not started, not winterized.
I got everything going, took a bit of running it and I put some seafoam in the tank, but appeared to be running pretty well today on the track.
RPMs are a little slow to return to idle when revved, but nothing I thought as a major concern.
2004 K&N pods, jardine exhaust, jetted accordingly.
blue smoke usually means your burning oil. either from worm piston rings, scored cylinder walls or a leaking valve seal. If its a white-blue smoke than thats either a incomplete combustion or injection system problems( maybe not the last one)
Quote from: mach1 on July 16, 2008, 03:44:14 PM
blue smoke usually means your burning oil. either from worm piston rings, scored cylinder walls or a leaking valve seal.
Mach1 is right on, but I wouldn't be too worried unless its and excessive amount of smoke. GS's are notorious smokers at high rpms and closed throttle conditions. In fact I just rebuilt my motor this winter and still if I am above 9K and close the throttle all the way I get a little puff(or so I am told). I honed the cylinders,new rings, re-used the pistons, but everything was within specs. The head was redone with new valve-seals and all, yet it still smokes a bit. Infact half of the GS that race smoke at high rpm and closed throttle so I am not sure if it is just a piston-wall tolerance issue or what.
As can be seen below.
(http://www.momentumphoto.net/events/cra/08jul/220/images/CRA08_BIR07_C806.jpg)
the instructor riding behind me came by afterwards and said he could smell it. some people have said valve guide seals. know anything about this??
Oh yea valve seals made of sheite ... yup. Not that that is the only POS in this bike though.
Rings, valve guides themselves, etc etc ...
Cool.
Buddha.
how difficult is it to replace it all? I've never even checked the valves myself lol.
hah, i have the exact same problem on my 04, 16,XXXmiles, oil changed regularly, no engine mods
did one trackday weekend and it was fine. this past weekend, i was smoking on downshifts and someone told me about it. I guess i won't do anything since it doesn't appear to be affecting power.
I would not worry about it. Run it as is. It is just a track day, not a race. If you are still concerned, wait until winter then rebuild the top end.
In 48K my 89 never smoked ... ever. Used plenty of oil, just not by smoking it.
But, track bike - just watch it and keep it up with fresh - you run 0wt right ... may use 0wt and not if you had 20/50.
Cool.
Buddha.
if it's valve stem seals, it'll be really bad on startup, and then not do it very much at all the rest of the time
Quote from: The Buddha on August 05, 2008, 08:12:58 PM
In 48K my 89 never smoked ... ever. Used plenty of oil, just not by smoking it.
But, track bike - just watch it and keep it up with fresh - you run 0wt right ... may use 0wt and not if you had 20/50.
Cool.
Buddha.
where did the oil go then oh semi- wise one :dunno_white:
Plenty of theories, I have had liquid oil get out of the exhaust like a fine spray coupled with water, carbon and gasoline upon revving up.
Rev up with you hand behind there and you'll get black fine misting spray.
Cool.
Buddha.