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

250-500cc Blew up my 2012 WR300

Discussion in '2 Stroke' started by Motovet45, Aug 8, 2013.

  1. Motovet45 Husqvarna
    AA Class

    Location:
    California City, Ca
    Husqvarna Motorcycle:
    WR 300
    2 laps in on my new HTM "black edition" head she blew the helicoils right out of the cylinder along with all the head bolts! Apparently she wanted race fuel and I only fed her premium, oops!!! image.jpg
    Motovet45, Aug 8, 2013
    #1

  2. juicypips Husqvarna
    Pro Class

    Location:
    gloucestershire
    Husqvarna Motorcycle:
    wr 360. 2002
    Other Motorcycles:
    Gas Gas TxT 300, Yamaha wr250f
    ohh dear thats not good. htm have a lot of compression then..:eek:
    juicypips, Aug 8, 2013
    #2

  3. MOTORHEAD Husqvarna
    Pro Class

    Location:
    Mount Vernon, Indiana
    Husqvarna Motorcycle:
    none
    Other Motorcycles:
    2014 YAMAHA YZ250
    I don't think that's what happened. Your piston wouldn't look that good if detonated from low octane.

    What does the exhaust side look like? How about the head and cylinder?
    MOTORHEAD, Aug 9, 2013
    #3

  4. Motovet45 Husqvarna
    AA Class

    Location:
    California City, Ca
    Husqvarna Motorcycle:
    WR 300
    Cylinder was in great shape, head had some signs of detonation. HTM said they've never had that happen before but they also said you need to run 110 octane race gas with the head. I thought maybe I screwed the squish up at 1.0 but the shop I took the head and cylinder to checked it and I was right on, they also compared the HTM head to the stock head and the HTM's lip was 20 thousands smaller on the inside diameter. So I'm having them clean up the HTM head, remove that 20 thousands from the lip, ball hone the cylinder, port it and put timeserts in place of the helicoils that pulled out. I'll run race gas and see how she goes.
    Motovet45, Aug 9, 2013
    #4

  5. MOTORHEAD Husqvarna
    Pro Class

    Location:
    Mount Vernon, Indiana
    Husqvarna Motorcycle:
    none
    Other Motorcycles:
    2014 YAMAHA YZ250
    Looking at the piston I'd say that .020" of diameter is what caused the problem. See the little ring around the top of your piston? Looks to me like it was contacting the lip in the head.
    MOTORHEAD, Aug 9, 2013
    #5
    Johnnymannen likes this.

  6. ray_ray Mini-Sponsor

    Location:
    The Philippines
    Husqvarna Motorcycle:
    08\013 WR250, 010 TC250, 012 TC250
    That is a weird clean looking piston and I think I can see that mark around the edge of that piston ...


    --
    Was it knocking before it went off?
    ray_ray, Aug 9, 2013
    #6

  7. Motovet45 Husqvarna
    AA Class

    Location:
    California City, Ca
    Husqvarna Motorcycle:
    WR 300
    I was thinking the same thing, that's why I'm having them take the 20 thousands off. I know a few people on here have been running this head and have had no problems, I was shocked when she blew. I did not enjoy the push of shame back to the truck.
    Motovet45, Aug 9, 2013
    #7

  8. Motovet45 Husqvarna
    AA Class

    Location:
    California City, Ca
    Husqvarna Motorcycle:
    WR 300
    It's the stock piston, bought the bike brand new in January for $5400 OTD. It wasn't knocking at all before it went, I came out of a corner hit the throttle and "pop" I had radiator fluid all over my boots!
    Motovet45, Aug 9, 2013
    #8

  9. firecrackerkid Husqvarna
    AA Class

    Location:
    Grand Coulee, Washington
    Husqvarna Motorcycle:
    78 390 OR, 84 250WR, 83 175WR
    firecrackerkid, Aug 9, 2013
    #9
    Motovet45 and Glenn haynes like this.