Blue Smoke from Packing?

[m250r]

Can blue smoke coming out of the pipe be caused from the exhaust that needs to be repacked? Thanks

[lol]

i'm guessin tht hes tlkin bout the 300 in his sig....4

[m250r]

its a 4 stroke..400ex though..im thinking about buying one and the kid thinks that it needs repacking

[xX-400racer-Xx]

blue smoke definately has nothing to do with the silencer. if you have blue smoke thet more than likely means that the piston rings are bad and the motor needs a rebuild. whats happening is the rings have gotten too hot or have worn out and are letting oil past them into the combustion chamber and is getting mixed with the gas.:( .......... but make sure its blue smoke, if it is black that means that the motor is running rich which in that case the only bad thing is that you will trade slightly longer engine life for worse gas milage and going through spark plugs MUCH faster and a power decrease. in either case it has nothing to do with the silencer

[m250r]

****CORRECTION****
It blows whitish black smoke and only on the startup..can this be caused by the packing? Thanks

[mojoe2878]

it may just be some oil leaking past the valve seals. ive never seen one start smoking from bad packings, they usually just get louder and start losing a little performance.

[airheadedduner]

Blue smoke is oil, a blackish smoke is excess fuel. Yes it is fairly normal for thumpers to do that a little on startup and then clear up real quick once they get warm.

[quad_62]

if it's just a little puff of white smoke at startup, it could also be condensation in the exhaust. mine does this in cooler weather.

[exrider360]

my 300 dose it on start up then goes away a few seconds l8ter