KTMonda CR500 450sxf conversion

Discussion in '2 smokers' started by jar944, Jan 20, 2012.

  1. Navin

    Navin Long timer

    Joined:
    Sep 22, 2009
    Oddometer:
    10,383
    I've got a 07 SXF450 frame in NJ if anyone is looking, assorted pieces to assemble too sub, axels, tanks, etc..
    #61
  2. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    The Oct issue of dirt rider magazine profiles a KTM cr500 hybrid.
    #62
  3. lessongeo

    lessongeo n00b

    Joined:
    Sep 11, 2012
    Oddometer:
    2
    Can a guy buy some spacers for the swing arm/cr500 motor ?

    I am looking to convert my ktm 2008 250 xcw into a cr500 powerplant as well...what airboot works?
    #63
  4. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    Typically you need to find someone with a lathe or find a fab shop.

    Your stock 2t air boot is the correct one.
    #64
  5. lessongeo

    lessongeo n00b

    Joined:
    Sep 11, 2012
    Oddometer:
    2
    cool thanks. Wish me luck...I will start posting pics and start a thread once the powerplant hits my garage.

    I started the teardown tonight.

    Hell, there's no replacement for displacement.
    #65
  6. Reino

    Reino Been here awhile

    Joined:
    Nov 21, 2011
    Oddometer:
    275
    Location:
    namibia
    Ride report or a video is in order!:wink:
    #66
  7. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    Went climbing this weekend. It was the first time riding this bike since June.

    I was having detonation issues last time out and cut the head to try eliminate the issue (on pump) It may have helped a bit but by the 3rd hill I was pinging again. I switched to 50/50 94/100LL and it stopped.

    The decomp was sticking partially open (from the cable setup) It looks like I need to rethink the routing and attachment.

    Jetting was off, rich pilot, lean needle (diameter) made a really rough transition at low throttle openings. The DGN does not work on my bike.

    The kicker is killing my foot. 90% of the time I slam the top of my foot into the peg. i machined up a spare spline/pivot to accept the ktm kicker, but w/o the decomp there is no way you are kicking it over. a gen5 crf450 kicker was suggested as a possible option, I'll have to look into it more.
    #67
  8. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    Old3?
    #68
  9. Reino

    Reino Been here awhile

    Joined:
    Nov 21, 2011
    Oddometer:
    275
    Location:
    namibia
    How do you think this compares to the 440 conversion they do on the 250sx?
    #69
  10. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    The 440 likely makes more power, but Big-Dog had somewhere around 5K in the engine alone to get there. Then if you break something, trash the cases/cylinder/crank you are paying $$$$ for custom parts again.

    http://ktmtalk.com/index.php?showtopic=393440
    #70
  11. Reino

    Reino Been here awhile

    Joined:
    Nov 21, 2011
    Oddometer:
    275
    Location:
    namibia

    Jip i looked at that thread a long while ago, The biggest i would go is 300 with my ktm and i cant do the cr500 conversion parts and motor are not really available here. i think there are a total of 5 or 7 cr500 in my country. Its a bummer.
    #71
  12. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    His conversion was based on 250 cases and a 380 crank and top end.

    a straight 380 swap is easier and cheaper
    #72
  13. Reino

    Reino Been here awhile

    Joined:
    Nov 21, 2011
    Oddometer:
    275
    Location:
    namibia
    Jip i agree, if he wanted something Big bore he should have got the 380 engine and bored it out to get that extra 20cc. Than he would have an 400 2t, not a 440 but close.

    I wish i could get my grimy hands on a 380 engine, but i have never seen one in person and i don't thing there is one in my country.

    I had the chance one an 1999 cr500 for 3500 usd, but decided agents it and got an 250sx instead. I didn't want my parents to worry about me on the cr.
    #73
  14. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    #74
  15. anonny

    anonny What could go wrong?

    Joined:
    Mar 20, 2007
    Oddometer:
    6,067
    Location:
    Beautiful Revelstoke BC
    Thanks for posting the vid, was great to watch. Looks like it works pretty good.
    #75
  16. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    Thanks. As soon as I get the jetting sorted out it should be fantastic.
    #76
  17. davi

    davi Adventurer

    Joined:
    Oct 18, 2008
    Oddometer:
    19
    Location:
    Medellin, Colombia. Philadelphia, United States
    Great build man. I am really interested in doing the same build but with 2011 or 2012 ktm frame but dont know which model to chose for a new cr500 engine from Service Honda. do you know the cr500 engine dimensions and the mount dimensions or where i can get them?. i would greatly appreciate it
    #77
  18. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    Get the 450sxf, the cr5 motor is very very close in size to a RF4
    #78
  19. davi

    davi Adventurer

    Joined:
    Oct 18, 2008
    Oddometer:
    19
    Location:
    Medellin, Colombia. Philadelphia, United States
    yea but the 2011-2013 450 sxf has a different shaped frame and has a linkage mono shock. i would like to fit it in a 300 exc (xc-w) but i need cr500 engine dimensions with the mount and exhaust measurments so i can measure some of the ktms. could you wright the measurments down o tell me where in the web i can get them. i would greatly appreciate it
    #79
  20. jar944

    jar944 Been here awhile

    Joined:
    Aug 2, 2010
    Oddometer:
    899
    Location:
    Chantilly VA
    The 07-12 450sxf has the exact same engine. The cr5 will fit in any RF4 frame.

    It will not fit in a 300/250 frame with out a cradle swap

    250sx vs 250sxf vs 450sxf
    [​IMG]

    compare that to the 500 in a 450 frame and you easily see where the issues are
    [​IMG]
    #80