Oil and smoke problem on XL600LM
 

Hello,

I recently changed the valve seals on the bike and a stainles stail exhaust. So i adjusted the air/fuel mixture on the carbs a bit. But did 650 k‘s friday and when i opened the trottle it gave black smoke at the exhaust. And it needed about 450 ml of oil for these 650 k‘s. Which is a bit too much as i thought.
Does anyone have an idea what the problem could be? Any help is welcome!
On Saturday I worked on the bike with a mekanic here in Bangkok, as he‘s also a friend. He tels me that the black smoke is because of too much fuel. So i moved the clip from the carb‘s one groove up so the needle comes more down and less fuel comes through. When i started the bike,there was still black smoke. He told me cause of the black carbon that‘s still in the exhaust(which could be true i guess).
He says the oil consumption is normal in these hot conditions. Although i have my doubts about that part. As i never used so much oil before.
Can anyone tell me which symptones there would be if the pistonrings where gone? I checked the airfilter-case and there was no excesive oil in there,so that should be an ok symptone i thought.Some people suggested to check the oil level in the carter as well. If there's too much oil,they say it could indicate a problem with the oilpump. But can‘t try it out at the moment as i‘m still in the city. I ‘ll check that part if i take of from here further to the south again.
I also took out the sparkplug and it was a bit gray but wasn't oily at all.Wich is again a good sign concerning the pistonrings,no?
Thank you!

Cheers,Bossit!!

Maybe is time to rebore your cylinder cause it become ovalized too much and rings cannot seal ?

AnteK

you could try doing s compression test on the cyclinder to see if its low. implying cylinder wear.

you need a special guage to go into the plug hole to do it.

you need to know what it should be as well!

The black smoke definitely sounds like mixture rather than oil (normally a more whitish smoke). However, after takling the valve guides I would have thought the problem is more likely to come from that area, seeing as you don't seem to have had this problem before the guides were disturbed. Are you sure you were suplied the correct parts?

Stig

Hello,

By this time i took the bike apart and found out i need new pistonrings,etc...
The big question is which option do i take?
1. Rebore the cilinder and use an oversize piston with rings and new gaskets
2. Put a whole new sleeve with the original diameter and use the old piston with new rings
Another thing is :do i put a new cam chain or do i leave it.
Do i need to change the black plastic guides as well?
If ai have to change all this it's gonna be a pretty expensive bill a guess?
Anyone, who can give me some agood advice?
It's pretty urgent !

Thank you,
Cheers, Bossit


[This message has been edited by Bossit (edited 10 April 2005).]