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[Clement]

Hi All

Went for a short ride this morning and, after switching off, noticed white smoke coming out of the carburetor through the air filter; carburetor and air filter still cool to touch; lasted 4 minutes or so; hope somebody has an idea about what's causing this.

Cheers

Fredo

[papasmurf]

Check the air filter, is a there is a segment at the bottom soaked in oil, it would suggest over filling with oil.

[Bullet Whisperer]

Hi Fredo, It might just be down to the position of the crank when the engine stopped, after switching off. It might have been about to fire when switched off [no spark] and rolled back a little, opening the inlet valve again by a small amount and thus producing a thick, white fog pouring out of the intake. I have seen it on occasions and it is nothing to worry about. On kickstart bikes, you can stop it by giving a nudge on the kickstart, to put the engine on compression, where the valves will be shut. regards, Paul.

[Clement]

Hi Paul

That seems to be what it is; thanks!

Fred

[jefrs]

I think Paul has it there. The compression and power strokes will both will both, like an air gun, make the motor tend to stop with a valve open. The white mist may be more apparent on moist humid days.

[ric]

but before walking away we all ensure the engine is left with both valves closed don't we ?

[Rattlebattle]

Used to happen a lot in the old days with carbs fitted with bellmouths. Sometimes you could see a swirl of white vapour coming out of and then being sucked into the bellmouths. Used to put a sink plug in my Goldie one...

[Thack]

Ric writes: "but before walking away we all ensure the engine is left with both valves closed don't we ?"



Completely pointless. It's only due to it being a single that we can arrange for all the valves to be closed anyway - three and four cylinder bikes always have at least one valve open, and nothing terrible happens to them.



If you are going to store it in a damp shed for fifty years, there might be an argument for it. But even then it's only a "might".

[jefrs]

ric - (rofl) no, I can think of better things to do, like oiling the chain or making a cuppa After getting off the bike at my age first priority is probably having a pee