1. Husqvarna Motorcycles Made In Sweden - About 1988 and older

82 cr250 cylinder

Discussion in 'Vintage/Left Kickers' started by Bigbill, Dec 21, 2017.

  1. Kartwheel68 Husqvarna
    Pro Class

    Location:
    Newnan, Georgia
    Husqvarna Motorcycle:
    82 125XC, 250XC, 430XC, 430WR, 250CR
    Other Motorcycles:
    83 175WR , 76 250WR, 74 250 Mag
    What? That is absolutely not true at all.
  2. fran...k. Husqvarna
    AA Class

    Location:
    eastern ct
    Husqvarna Motorcycle:
    420ae 98wr125 2004wr250 others
    Other Motorcycles:
    electric freeride 1993 yam gts
    I was able to resist replying to that one.

    My take is with the power valves in Husqvarna motorcycles one gets better low rpm power and a lot less noise while down there. My 2004 WR250 says 42 sae hp on the certificate of origin, what do you think was on the certificate of origin for what this thread title is?

    I believe Bill's statement is true if one is to take the balls out of the power valve governor.
    oldbikedude likes this.
  3. justintendo klotz super techniplate junkie

    Location:
    mercer, pa/northwest pa
    Husqvarna Motorcycle:
    84 250,86 400,87 430,88 250,95 360
    Other Motorcycles:
    99 kawasaki zrx 1100
    the sound levels you speak of are very noticeable..power valve bikes are very quiet until the valve opens!
  4. justintendo klotz super techniplate junkie

    Location:
    mercer, pa/northwest pa
    Husqvarna Motorcycle:
    84 250,86 400,87 430,88 250,95 360
    Other Motorcycles:
    99 kawasaki zrx 1100
    more nonsense..
  5. Kartwheel68 Husqvarna
    Pro Class

    Location:
    Newnan, Georgia
    Husqvarna Motorcycle:
    82 125XC, 250XC, 430XC, 430WR, 250CR
    Other Motorcycles:
    83 175WR , 76 250WR, 74 250 Mag
    I changed my original reply before I posted, it was less diplomatic.

    To bill, by having an "adjustable" exhaust port height, you get both more bottom end power AND more top end power than a non power valve engine. A power valve WILL do what you said if it is not functioning correctly and is stuck in the down position, it will then add power down low and rob power from the top. If it is functioning correctly you get the best of both, which is why all modern two strokes from the mid-80s on have had them.
  6. Bigbill Husqvarna
    Pro Class

    Husqvarna Motorcycle:
    '83 250wr
    Other Motorcycles:
    0 right now
    Then how come the power valve bikes aren’t as fast top end wise as the non power valve bikes?
  7. silverstreakNZ Husqvarna
    Pro Class

    Location:
    Christchurch nz
    Husqvarna Motorcycle:
    82cr500,76gp360,90wr250,81 420AXC
    Other Motorcycles:
    74 tm400 , 02 gasgas ec 300
    I was going to reply to that . Deleted everything I wrote .
    Face palm bill
    justintendo likes this.
  8. fran...k. Husqvarna
    AA Class

    Location:
    eastern ct
    Husqvarna Motorcycle:
    420ae 98wr125 2004wr250 others
    Other Motorcycles:
    electric freeride 1993 yam gts
    Example please. Non power valve engine on KTM two cycle freeride as compared to any current 2cycle Husqvarna. Is not as you imply.
  9. Kartwheel68 Husqvarna
    Pro Class

    Location:
    Newnan, Georgia
    Husqvarna Motorcycle:
    82 125XC, 250XC, 430XC, 430WR, 250CR
    Other Motorcycles:
    83 175WR , 76 250WR, 74 250 Mag
    Fast, as in miles per hour or power on the top end of the rpm range? If you are talking about top MPH that has to do with transmission and secondary drive ratios. If you are talking about top end RPM range power, power valve engines make more top RPM power. They are not the same thing.
  10. justintendo klotz super techniplate junkie

    Location:
    mercer, pa/northwest pa
    Husqvarna Motorcycle:
    84 250,86 400,87 430,88 250,95 360
    Other Motorcycles:
    99 kawasaki zrx 1100
    yeah but not like a 390..on those the tire never stops spinning.
  11. Bigbill Husqvarna
    Pro Class

    Husqvarna Motorcycle:
    '83 250wr
    Other Motorcycles:
    0 right now
    The fastest dirtbikes,,,,,,,think about the 500cc husky that was posted here at 123mph a while back.


    View: https://m.youtube.com/watch?v=LMbSn7Ijo7k

    My drag race car ran the 1/4 mile in 12 seconds. I know my 99 husky wr 250 turned in the same times.
  12. Bigbill Husqvarna
    Pro Class

    Husqvarna Motorcycle:
    '83 250wr
    Other Motorcycles:
    0 right now
    Trust me the only time the rear wheel on the 390cr stopped churning was when I shifted it. I was on the throttle all the time she was wicked.
  13. 87husky500xc Husqvarna
    Pro Class

    Location:
    Dayton NV
    Husqvarna Motorcycle:
    2020 tx300i and a few vintage bikes
    Other Motorcycles:
    77 honda xr-75..
    The difference is in the transmission.... all the factories didn’t just go to a system that sucks. There is a reason that every modern two stroke has one.
  14. oldbikedude Husqvarna
    Pro Class

    Location:
    Honey Brook Pa.
    Husqvarna Motorcycle:
    1988 wr 430 with cr suspension
    Other Motorcycles:
    66flh,67 CA77,76 CR125M,73H1,74ty250
    Fake news......lol
  15. Bigbill Husqvarna
    Pro Class

    Husqvarna Motorcycle:
    '83 250wr
    Other Motorcycles:
    0 right now
    It was told to me that the power valve takes the rpm/speed from the top end and puts more power on the bottom end.

    The air cooled bikes have more topend with no power valve. Maybe I was told wrong.
  16. 87husky500xc Husqvarna
    Pro Class

    Location:
    Dayton NV
    Husqvarna Motorcycle:
    2020 tx300i and a few vintage bikes
    Other Motorcycles:
    77 honda xr-75..
    The air cooled bikes from seventies and early eighties will never have the top end that the new p/v bikes do. A power valve just reduces the size of the exhaust port at low rpm to create a wider power band and opens as the rpms increase to let the exhaust flow at necessary rate for maximum performance on top. This makes for a more rideable bottom end while also being able rev out from mid to top quite quickly. Ever ridden a bike with a stuck power valve? It sucks(this experience comes from other people’s machines, not my own haha)
  17. Kartwheel68 Husqvarna
    Pro Class

    Location:
    Newnan, Georgia
    Husqvarna Motorcycle:
    82 125XC, 250XC, 430XC, 430WR, 250CR
    Other Motorcycles:
    83 175WR , 76 250WR, 74 250 Mag
    You were told wrong.
  18. fran...k. Husqvarna
    AA Class

    Location:
    eastern ct
    Husqvarna Motorcycle:
    420ae 98wr125 2004wr250 others
    Other Motorcycles:
    electric freeride 1993 yam gts
    For comparison I found some pictures of the insides of the 250 ktm freeride two cycle cylinder. It is a case reed unlike the bikes in this section. I think it is kind of a price point bike for example no counter balancer no damping clutch, no power valve. There may be other 250 non powervalve engines out there but this is the only one from the current parent company of Husky. Trials bikes may well also be non power valve. Not sure what is out there in other parts of the globe.

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  19. Bigbill Husqvarna
    Pro Class

    Husqvarna Motorcycle:
    '83 250wr
    Other Motorcycles:
    0 right now
    Doesn’t the power valve change the exhaust port timing? When it opens the exhaust port it exhausts hot gasses sooner? When it’s closed it lowers the exhaust port and gives more bottomend.
  20. SteveJ Husqvarna
    AA Class

    Location:
    New Mexico
    Husqvarna Motorcycle:
    1970 400 Cross, 1983 500 CR
    Other Motorcycles:
    84 Honda CR500R, 81 Honda CBX,
    Yes, but a power valve engine can have exhaust port timing that is more aggressive to begin with, since the power valve can tame it down for bottom end.