Dakar: KTM great but why not 2-strokes?

Discussion in 'Racing' started by SnakeBreak, Jan 27, 2013.

  1. SnakeBreak

    SnakeBreak Been here awhile

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    So I watch as much of Dakar as I could and the top riders are riding KTM 450's. Why not 2-smokes? Why 300exc is way simpler to fix and has less to go wrong? In the USA I would say it is rules against 2-strokes on the road, but down there?
    #1
  2. STisma

    STisma Been here awhile

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    I think it has to do with the torque.
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  3. Katoom72

    Katoom72 Been here awhile

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    Long stretches of WFO and 2stroke don't go well togeather.
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  4. SnakeBreak

    SnakeBreak Been here awhile

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    Why is that? I am sure you right but I do not understand why. It seems a 2-stroke 400 or 600 would make massive power /weight and you would not have to run WOT. They put 2-strokes in boats and they run WOT all the time.
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  5. Racer111v

    Racer111v Been here awhile

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    Baja has been won many times by 2Ts. It doesn't get much more wide open than that. But the manufactures want to sell 450 4Ts, so guess what they race.
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  6. crofrog

    crofrog Long timer

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    when they aren't jetted right...

    but 2 strokes seriously suck gas which would add allot of weight for a dakar bike.
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  7. Brokein2

    Brokein2 Been here awhile

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    I don't know about you, but I would not want to try and figure out proper race jetting for a day that has a 3000 meter elevation change. Maybe fuel injected 2 strokes would be ok....
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  8. WARRIORPRINCEJJ

    WARRIORPRINCEJJ Not in the clique...

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    Luis!!!


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  9. crofrog

    crofrog Long timer

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    not really that different the carbed 4 strokes though.

    FI brings it's own problems ask HRC
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  10. tHEtREV

    tHEtREV Captain Awesome

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    Fuel consumption.

    Any weight saving from a two stroke is taken up by the extra fuel it would have to carry.

    My 200 used to use 10l per 100k on gravel roads taking it easy, my 4 strokes use between 5 and 6 liters per 100k.

    Considering 30l was not enough for an FI 450 ridden by a front runner, how much fuel would you need for a 300 2t?
    #10
  11. Yellow Pig

    Yellow Pig Allergic to Asphalt!

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    Plus the oil you have to carry for refueling
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  12. snarf

    snarf WFO and clueless

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    Sure they do. 500s used to rule the desert for years and years.
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  13. snarf

    snarf WFO and clueless

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    Most of the time, guys allready mix the premix in, before they take the fuel to the fuel stops.

    2T uses more fuel than a 4T?

    If its not jetted right, sure they do. My 300 sips gas, why? Because its jetted right, lol.. I get 35+ mpg out of it just tooling around, and about 30 at race pace.

    Manufacturers DONT WANT to race the 2T's, otherwise they would. Thats why.
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  14. crofrog

    crofrog Long timer

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    Either your bike is dangerously lean or your idea of race pace and mine don't line up at all. I get about 20 out of my 200 during race. Jetted for max power clean plugs and no spooge.
    #14
  15. toro618

    toro618 Been here awhile

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    Sorry to hijack, but how do you avoid no spooge? I always thought even if jetted perfectly, the motor will not burn 100% of the 2T oil.
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  16. tHEtREV

    tHEtREV Captain Awesome

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    This has been discussed a few times before,here is one of the threads I found while researching my sensible and thought provoking response (OK, I was looking for the pics of that 300 Rallye bike Sommer built).
    #16
  17. snarf

    snarf WFO and clueless

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    Difference in riding styles, I'd guess. I've historcally gotten really good mileage out of my tanks.. I short shift a lot and carry momentum. I dont go WOT very often. I'm sure you probably ride that 200 more agressively than i ride my 300 :)
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  18. NHESS81

    NHESS81 Adventurer

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    Ok, so it can have race pace...but how practical is that pace on the 100-400 miles of DAILY transit stages bookending the daily race stages? Seems like it wouldn't make a 2T happy to drone on the highway for 5 hours a day....
    #18
  19. crofrog

    crofrog Long timer

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    It won't burn all of it, but what it doesn't burn will stay in the engine / pipe versus running down the back of your silencer.
    #19
  20. Lc8grrr

    Lc8grrr Vtwin madness

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    Owned a Yamaha RD350 2T twin years ago. You could ride on the highway all day (is a roadbike). Quick as a 750/4 or more. You'd build a 2T Rally as a twin not a single and with air injection which is supposed to be frugal on fuel. I thought KTM were rumoured to be onto air injected 2Ts in R&D? :ear
    #20