oil breather thingy smoking

[dreadmanbastard]

hey,

can anyone tell me whats going on here.

behind the cylinders and the cam chain tensioner is a silver round flat topped 'pot' with a hole in the top which i belive is the oil breather (no idea what it does). correct if im wrong.
there is a putting of air releasing from it at tick over and a fair amount of smoke. this sounds bad. isit? smoke is always bad. its not thick or in great plumes but enough to see. (and smell)

im worried

[Pigford]

That thing is the crankcase breather/oil seperator.

They do tend to smoke a bit..... A pipe should be connected from the take off to the under side of the air box.

A lot of smoke indicated crankcase pressure build up. This is often down to worn piston rings But some smoke/vapour is expected even on a perfect engine.

Inside is a baffle plate with 2 x curved plastic pipes. This arrangement is often removed to reduce crankcase pressure as they don't work that well.

[dreadmanbastard]

right ok, ill keep an eye on it. i had the engine rebored to 1070 with wiseco pistons, recondition crank etc about a year and a bit ago, and havent done loads of miles, so it shouldn't be the rings.

you say they are often taken out. is taht something that would be worth doing? is it straight forward?

cheers.

[Pigford]

If there is a problem with the engine (which I'm not implying ) this won't cure it.... but....

The breather arrangement is a bit restrictive..... All you need to do is unscrew the bolt remove the cover & the baffle is held in place by 2 x screws. Undo them & chuck the baffle (c/w pipes) in the bin

Try it - nothing to loose.

If the bike hasn't been run for a while, it could just be excess moisture being burnt off..... Next ride out, make sure you do a good 50 mile run to clear the bike out.

[kano]

is it defiantly smoke?
could be water in the oil evaporating?
i have a 10 inch rubber tube with a little filter on mine.



racers i believe ran the tube into a catch can didn't they pig?

[Magnum1]

I run mine out under the seat. Sometimes when I'm at the lights, smoke comes out and goes in car windows. The drivers dont look very happy and tend to put their windows up. Makes me feel very guilty. Maybe I should write to the MCN problems page?

Rod

[Steve R]

Just got a filter on top of mine little K and N one, having read this will remove that baffle plate you are on about Mark, Save some more weight!!!

[floydsz1]

Kano's correct in that when we raced them we ran the pipe into a catch tank. Had to empty it now and again as it slowly filled with oil/water/crap etc.Even with modern bikes its the same. Normaly on a road bike it is fed back into the airbox and through the carbs and is burnt with the exhaust gas.