Smoke????

[mulisha_85]

I have a yz 85 and i change the oil regularly and mix the gas right and clean it.... but it smokes really bad and i think its because i need a new top end, but not sure, how much do you think i will spend on a new top end? And also i haven't gotten a new top end for like 6 months:( :( :(

[savage destruct]

Your do...since you have such a little bike and most likely have been riding it hard...and it will only cost you like 30 dollars for rings and remember you need to change your gaskets so if you go with dennniskirk.com you will only spend about 45 dollars....When you change your top end, clean your powervalve and piston....decarbonize it.....check reeds and such for power wise and check for the smoke....the rings should do it but if that doesn't help try mixing with a little less oil, not much or you could seize you piston...whats your mixture?

Hope i helped alittle!:D

[gristle]

does it still run good then it doesnt need rebuilt it prolly needs jetted a little leaner it should stop smoking you could move the clip up one or two positions on the needle or get a leaner main jet
________
WELLBUTRIN SIDE EFFECT (http://www.classactionsettlements.org/lawsuit/wellbutrin/)

[ont.freerider]

i heard slider talkin about blown crank seals, it sucks the tranny oil through the seal and to the piston, then it burns it and smokes like stank! but i think that would be some serious smoke cause burning tranny fluid will be some seriously thick smoke

i doubt its your top end dude. id be lookin at the jets first myself. that first. wait for slider to explain the crank seal thing better, ive never had any experiences with that so i couldnt tell ya. good luck. and rememeber man, rich is better than lean.

[slider]

It was really bad. I toasted two jerseys due to oil spots all over the backside. No mosquitoes around the riding place so I waited a couple weeks b4 changing them. lol.

Anyhow, this subject keeps coming up and seems to always bring the question - what oil and what ratio? I don't know if a top end job would solve or reduce the smoke but one thing I do remember from a mag a long time ago is: If you see smoke out the silencer, you have good lubrication.

The more oil to gas ratio you run, the better the bike will run. But, when you get more than 20:1, you will foul plugs. A 250 can make 1 full horsepower or more with 20:1, even more at 16:1. Problem is the bike usually fouls a plug b4 the dyno run is finished.

So, some smoke = OK.

Oh, I live in Arizona so there are never any mosqitoes.

[SCAR8]

Originally posted by ont.freerider
i heard slider talkin about blown crank seals, it sucks the tranny oil through the seal and to the piston, then it burns it and smokes like stank! but i think that would be some serious smoke cause burning tranny fluid will be some seriously thick smoke

yep that could be it .my bike is bad about blowing crankseals its a yz 80 also but you can tell cause the smoke smells all funny and stuff . if that dont work just make it run leaner or if it is black smoke and bogs you might need to repack your pipe hope that was some help!!

[Cory_3xMx]

honestly, i would have it looked at by a pro...

if you keep riding it, it could tend to cease, and thats a big banana to peel...

[ont.freerider]

actually its less likely to cease if there is lots of smoke, smoke means lubrication. my CR250 smokes a fair bit, i dont mind at all. makes me feel good that i see smoke, then i know my bike is runnin good.

[slider]

Yea, it bothers me to see RC's bike smoke when in the air. But, his bike makes lots of power.

[LWilson250]

A well jetted bike will make more power at any oil/fuel ratio then a poorly jetted bike.

I run my KX250 at 40:1 with BellRay H1R and it's just fine, most oil now-a-days can be run at a really lean ratio and protect well.

I still wouldn't run anything less then 40:1. In a larger engine you can run less oil, 125's and 80's should run 32:1 or 30:1 just to be safe.

Lee W.

[localboy]

maybe you should check the compression, then you'll know if its the top end or not. i don't know how much compression an 80 should have so you should ask at a dealer or something.

[SCAR8]

i run my 80 50:1 and it runs great any less it runs like sheeeeeeeeeeiiiiiiiit!