Smoking Sherco, Can anyone help? tried the obvious, cleaned the plug and air filter,blown the carb out with compressed air but still getting light smoke on tickover and then it is like something out of the old james bond movies when climbing hills, plumes of smoke. the bikes a 2000 sherco 2.9,all replys gratefully recived.

what mixture you running your bike on oil wise this may be the problem or if you dont rev the bike at high rpm very often it might be an idea to give it a good blasting out at some point and rev it really hard if that doesnt clean it then its probably your mixture so you might need less oil or even the mixture on the carb

what mixture you running your bike on oil wise this may be the problem or if you dont rev the bike at high rpm very often it might be an idea to give it a good blasting out at some point and rev it really hard if that doesnt clean it then its probably your mixture so you might need less oil or even the mixture on the carb

mix is about 75 mls to 5 litres shell optimax, had a pretty good thrashing on sunday (well it did for me) plus i have got the mix screw 3-1/2 turns out.

The engine can only burn the amount of oil that you put in it,not like a four stroke which can burn to much oil if the rings have gone.Are you sure youve got the correct oil and is the mix is correct??,also check pilot jet size and needle clip position.

It is somewhat normal to have some smoke after a hard run of high enging loads or high rpm as it burns off the excess oil that accumulates in the exhaust after putting around!

High octane "race gas" only multiplies the problem as it does not ignite as readily and more fuel residues tend to accumulate.

The current recommendations and usage by the folks in the US are:

80:1 mix of high quality full synthetic lube such as Maxima K2

93 octane pump gas(highest available here) runs fine in the later models

The bikes run fine, little smoke and little to none (hard) carbon residue buildup in combustion chamber or exhaust(which plugs the baffles).

Some of the simi-synthetic lubes may work, it all depends upon the blends, but I can tell you that I have used the Yamalube 2-R (highly acclaimed by Yamaha) in the same ratios and with no problems.

I can find no reason to run ratios as high as 50:1 with modern oils, in a trials bike that spends most of the time putting around, it only leads to waste and smoke!

It goes to show you that a novice rider could easily go to 90,100:1 ratio with a good oil and have no problems and less mess! And an easy removal ov two bolts will let you take a look to see how much carbon residue is building up in the header pipe, mine is clean!

Plugging up your engine and exhaust is just as bad as ruining it from lack of proper lube!

M2C

If the smoke is white and puffy (transmission oil) instead of blue gray (mix oil), check the crankshaft seals.

If your bike has always drooled you need to change the low speed jetting.

Putting less oil in the fuel will make the problem worse, 80:1 is a good start. The best course is to pick a ratio and fuel, then stick with it and jet the bike to that fuel.

Most synthetics now availible are of excellent quality. I like the yamalubeR for its low ash in my mx bikes. But I run K2 or H1R in my trials bikes. I can't decide which I like best.