1. 2 Stroke Husqvarna Motorcycles Made In Italy - About 1989 to 2014
    WR = 2st Enduro & CR = 2st Cross

250-500cc lots of smoke, then no smoke...

Discussion in '2 Stroke' started by Loco, Sep 6, 2015.

  1. Loco Husqvarna
    A Class

    Location:
    Quebec
    Husqvarna Motorcycle:
    WR250
    Hi all, I took my bike to the trails yesterday, and while climbing a rocky hill, I fell. I started the bike half way up the hill, and paddled up to the top. I did push the engine a bit hard. After that, a lot of white smoke came from the exhaust with a different smell to it, and it lasted for a minute or so. I let the bike cool down and checked the coolant. it was a bit low (maybe 200ml). I filled up and then the smoke went away after a few more minutes of riding.
    Could this have been coolant that somehow got in to the cylinder? what could cause my engine to smoke a lot for a few minutes and then go away. I was using 1:40, but it never produces any smoke, only when it is cold.
    Any ideas would be greatly appreciated!
    Ed
  2. uranys Husqvarna
    AA Class

    Location:
    Pittsburgh, Pa
    Husqvarna Motorcycle:
    00 wr360/02 wr360/09 wr125/09 wr250
    Other Motorcycles:
    96 xr600r
    It's probably fine. Coolant should be level with the top of the cores, anything more will get blown out when it gets hot. The smoke and smell is oil burning off from your pipe and silencer packing because you got it hot.

    I'd also guess that your jetted a bit rich, but if it runs good don't change it.
  3. shawbagga Husqvarna
    Pro Class

    Location:
    Eaton, Western Australia
    Husqvarna Motorcycle:
    None
    Other Motorcycles:
    2018 Gasgas XC250
    200ml is a fair bit of coolant! did it smell sickly sweet as thats what coolant burning smells like generally? wasnt steam from overflow was it?
  4. lankydoug Husqvarna
    Pro Class

    Location:
    MO
    Husqvarna Motorcycle:
    WR
    Other Motorcycles:
    TM 300en
    Was the exhaust smoking or was there steam/smoke coming from the engine area? If smoke is coming out with the exhaust and smells like coolant it's likely from cyl head "O" rings failing. If it smells like transmission oil and your gearbox is low it's the clutch side crankshaft seal failing.

    If you fill the radiator to the top it will puke out coolant since there isn't room for the expansion when it gets hot. Filling it to just cover the cooling fins inside the radiator is the correct level.
    shawbagga likes this.
  5. Loco Husqvarna
    A Class

    Location:
    Quebec
    Husqvarna Motorcycle:
    WR250
    Thanks for all the replies, and here are some answers to the questions:
    I'm using IPONE 2t samourai, which is strawberry scented!!!, so yeah, it smells like crap, but not sweet like coolant. It did smell like if a lot of oil went into the cylinder, but don't know how. could it have been flooded while it was on the ground? I kept it running, but if the float opens up, can it all go in to the crank case and burn little by little? When I accelerated hard, it felt like if it was jetted too rich (blooowrrrrrrraammmmmmm), but it was only for a couple of minutes. It went back to zero smoke right after that, and the engine started responding as usual (brrrraaaammmmmm), not sure if you can imagine the sounds, don't know how to describe it better.
    And the smoke was coming right out of the pipe. No overflow or steam from anywhere else. No signs of overheated engine.
    Thanks again!!
    Ed
  6. oneal Husqvarna
    AA Class

    Location:
    uk
    Husqvarna Motorcycle:
    1999 wr 250 returned home.
    Other Motorcycles:
    07 TE 450 2005 TE 450 1999 CR 125
    Just a quick question are you using any transmission oil or noticed the level getting lower.
  7. Loco Husqvarna
    A Class

    Location:
    Quebec
    Husqvarna Motorcycle:
    WR250
    Oneal, I change my transmission oil every 3 times I ride, and no consumption of oil at all. I use motul transoil, and I put 800 ml and take 800 ml every time. The weird thing is that only happened for a couple of minutes and then stopped. I rode it again last sunday, and behaved like a princess!!! no smoke at all.
  8. lankydoug Husqvarna
    Pro Class

    Location:
    MO
    Husqvarna Motorcycle:
    WR
    Other Motorcycles:
    TM 300en
    You might have just got the pipe hot enough to burn out a bunch of old carbon build up. This can happen to an extreme and resemble a chimney fire that will burn until the carbon is all gone even if the bike is shut off
  9. gazmcfaza Husqvarna
    AA Class

    Location:
    uk
    Husqvarna Motorcycle:
    husky wre 125
    Other Motorcycles:
    , yamaha xt 125
    feel free to tell me I'm wrong as probably am, but on it's side, if the fuel and oil hadn't been mixed up very much, is it possible a big lumpy bit of oil could have gotten into the carb and been burnt more instead of the fuel temporarily? it would produce more smoke for a few seconds
  10. Oldscool Husqvarna
    AA Class

    Location:
    South Australia
    Husqvarna Motorcycle:
    None
    Other Motorcycles:
    RM125, SWM RS500R & Superdual
    Impossible if you've been riding, 2t oil mixes easily and quickly. I agree with the hot pipe theory.
  11. Loco Husqvarna
    A Class

    Location:
    Quebec
    Husqvarna Motorcycle:
    WR250
    Thanks for all the comments, and the theory of the hot pipe sounds probable, but it also affected the idle, and I know I mentioned a rich sound, but I meant a lean sound, when I accelerated, the motor would lag and sounded like it was starving for fuel. If it happens again, I will pay close attention to all the things that were mentioned.
  12. Oldscool Husqvarna
    AA Class

    Location:
    South Australia
    Husqvarna Motorcycle:
    None
    Other Motorcycles:
    RM125, SWM RS500R & Superdual
    The effect on performance could be due to the fresh fuel/air mix that enters the exhaust is being burnt instead of forced back into the cylinder (see expansion chamber theory).
    This is my theory anyway. Anyone care to confirm or correct.
    Loco likes this.