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

All 2st The future of two strokes

Discussion in '2 Stroke' started by tommie d, Jan 15, 2010.

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  1. Motosportz CH Sponsor

    Location:
    Vancouver WA
    Husqvarna Motorcycle:
    2021 TE250i, 570 Berg, 500 KTM, 790R
    Other Motorcycles:
    many
    that alone is BIG in regards to packaging the motor in the frame.
    Motosportz, Oct 8, 2010
    #21

  2. rasputin Husqvarna
    AA Class

    Location:
    Bavaria
    what orbital are normally comparing in their newer articles are a 450cc two-stroke and a 450 four-stroke engine. and - big surprise to all the two-stroke heads out there - they have found that the two-stroke gives more power. :banghead:
    http://twostrokemotocross.com/2009/06/two-strokes-strike-back/

    an issue that is often missed is that a tuned pipe is not only used to "re-gain lost fuel", it is also intended to re-gain lost air. the tuned pipe acts as a supercharger, more or less doubling the bmep, and therefor power. so of course you can go without the tuned pipe, if you double the engine capacity. way to go.

    r
    rasputin, Oct 8, 2010
    #22

  3. wallybean Mini-Sponsor

    Location:
    Montana
    Rasputin,

    Thank you for clearing that up. I also think that Orbital is having issues with getting their air/fuel injection system to work well above 6000 rpm. I am sure it is just an engineering problem that will be solved. I think that an expansion chamber is always going to be a part of a high performance DI 2 stroke. One of the advantages of the DI is that you can configure the engine architechure however you like(OSSA) and run the expansion chamber out the back which should be at least moderately more protected.
    wallybean, Oct 8, 2010
    #23

  4. rasputin Husqvarna
    AA Class

    Location:
    Bavaria
    high rpm are not an "orbital issue", it's a general "direct injection issue". the technology still has not advanced to a level where high rpm are not an issue. even for four-stroke motorcycle engines they still are a major issue. however, the orbital system is capable to go way beyond 6000 rpm, as the 450cc example is showing.

    r
    rasputin, Oct 8, 2010
    #24

  5. rockdancer Husqvarna
    Pro Class

    Location:
    Sunshine Coast, Australia
    Husqvarna Motorcycle:
    2013 WR125, 2019 FE350
    Thats a good article Rasputin . The 450 cc comparison of torque and horsepower on the on -line article look more realistic and are different to same 450 cc graph in this other magazine. Magazine graph shows 2 stroke much better - higher. Strange...
    Personally I hope the expansion chamber stays - I like it - looks cool
    Exciting times ahead though as long as they dont get too complicated
    4 stroke dominance may be just a stage

    I for one miss maybe the sound of the 2 strokes at the races...
    rockdancer, Oct 8, 2010
    #25

  6. wallybean Mini-Sponsor

    Location:
    Montana
    Thanks good to know. I read the 6000 figure in some article somewhere in my mind. It is probably just another example of old man CRS.
    wallybean, Oct 8, 2010
    #26
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