Call all XR600R!!!

Discussion in 'Thumpers' started by CSMonte, Dec 8, 2008.

  1. dedgerly207

    dedgerly207 Adventurer

    Joined:
    Apr 15, 2014
    Oddometer:
    88
    Tore into my 87 non runner today. I have a couple questions about the cam, head and cylinder.

    First the cam, is it normal to have the discoloration? Mine looks shiny at the lobe ends but possible the hardening has wore away some?

    My cylinder head has a lot of carbon build up. I am guessing by the score in the cylinder that it's burnt oil? Does the head look serviceable?

    Lastly, the cylinder has a good sized score on the intake side. Probably from not servicing the air filter or possibly from bottom end debris. I will find out soon. Can definitely feel the score with your finger. Does that look like a stock piston?

    IMG_20191215_185327027.jpg IMG_20191215_185300534_HDR.jpg IMG_20191215_144934003_HDR.jpg IMG_20191215_144938951_HDR.jpg IMG_20191215_133212477_HDR.jpg IMG_20191215_133159641_HDR.jpg
  2. msteward

    msteward Long timer

    Joined:
    Sep 14, 2015
    Oddometer:
    1,265
    Location:
    Spanish Fork, Utah
    No numbers on the top of the piston may be a good indication of a stock piston, cam followers in good conditions. Cam does not look terrible, as long as followers are starting to get chewed. Head can be cleaned up but needs torn apart to check the valves. More than likely needs intake valves and or exhaust valves. Sucking in dirt kills intake valves.
    Looks like a bore job is in order to get that scratch out.
  3. dedgerly207

    dedgerly207 Adventurer

    Joined:
    Apr 15, 2014
    Oddometer:
    88
    Got the cylinder off last night and found an XR's Only 100mm 11:1 CR piston apparently manufactured in 1991.

    Because there is a score on the cylinder wall I will need to bore the cylinder. Should I go up to the 102mm piston in standard CR? Is the 102mm bore and piston going to be reliable? Or should I resleeve back to stock size? I have also attached photos of the con rod. Does it look ok to return to service? IMG_20191216_190100838_HDR.jpg IMG_20191216_190006207.jpg
  4. msteward

    msteward Long timer

    Joined:
    Sep 14, 2015
    Oddometer:
    1,265
    Location:
    Spanish Fork, Utah
    Just about anything is reliable with proper care. I prefer to just go big enough to clean up what I got, so 1mm may get that out but it is hard to say how deep it is not being in front of me. I prefer a little less comp. ratio, closer to stock maybe up just a touch. 1mm=.040 so it might get that scratch out.
    Rod end doesn't show bad grooves but I have never seen one that didn't have some play in it. A little less compression will make it last a little longer
  5. lookfar

    lookfar from the land of OZ Supporter

    Joined:
    Feb 13, 2011
    Oddometer:
    1,439
    Location:
    D'aguilar
    If the spark plug is all the way in, it's reach is way too short. Needs to be to the end of the threads in the head.
  6. lookfar

    lookfar from the land of OZ Supporter

    Joined:
    Feb 13, 2011
    Oddometer:
    1,439
    Location:
    D'aguilar
    Nah, been fiddling with this one.
    Euro version XL600RMG. E-start as well as kick, twin carb, tubeless tyre type rims.
    A rare bike here in Oz.
    IMG_1845.jpg
    IMG_1846.jpg
    enduro16, thelastfoiter, BSW and 4 others like this.
  7. Al-X

    Al-X Been here awhile

    Joined:
    Dec 26, 2007
    Oddometer:
    379
    Location:
    Johannesburg, South Africa
    Tubeless rims as well?
  8. mcma111

    mcma111 Long timer

    Joined:
    Jul 17, 2007
    Oddometer:
    17,835
    Location:
    San Francisco,Ca.
    dedgerly207,

    Wiseco doesn't make any pistons bigger than 100mm for the XR600.

    XR's Only lists five oversize pistons for the XR600:

    Wossner 101mm, 9.3 cr, $185.00
    Wossner 102mm, 9.3 cr, $180.00
    JE, 101mm, 10.6 cr, $191.00
    JE 102mm, 10.8 cr, $180.00
    JE 103mm, 10.8 cr, $221.00

    I have a XR's Only (JE) 102mm piston in my XR600

    I'd like to see some close up pic's of the cam lobes and rockers.

    The cam is no longer available. Honda still has new rocker arms.
  9. lookfar

    lookfar from the land of OZ Supporter

    Joined:
    Feb 13, 2011
    Oddometer:
    1,439
    Location:
    D'aguilar
    Yup.
    But hard to find tubeless knobbies in 17" nowadays.
  10. dedgerly207

    dedgerly207 Adventurer

    Joined:
    Apr 15, 2014
    Oddometer:
    88
    MCMA1111,

    Requested photos below:

    IMG_20191222_155650875_HDR.jpg IMG_20191222_155655561_HDR.jpg IMG_20191222_155713526_HDR.jpg IMG_20191222_155807912_HDR.jpg IMG_20191222_155813204_HDR.jpg IMG_20191222_155838571_HDR.jpg IMG_20191222_155820704_HDR.jpg
  11. mcma111

    mcma111 Long timer

    Joined:
    Jul 17, 2007
    Oddometer:
    17,835
    Location:
    San Francisco,Ca.
    Looks good. Proceed with the build.
  12. dedgerly207

    dedgerly207 Adventurer

    Joined:
    Apr 15, 2014
    Oddometer:
    88
    I got a better photo of this rocker arm as it appears to have the most noticable wear. What do you think? I can feel a slight Mar on it with my finger. IMG_20191222_201423612_HDR.jpg IMG_20191222_201507939_HDR.jpg
  13. dedgerly207

    dedgerly207 Adventurer

    Joined:
    Apr 15, 2014
    Oddometer:
    88
    Oh and I found this in the bottom of the right side engine case under the oil screen. It's metallic. I have not found any big damage so not sure where it came from.
    IMG_20191222_202422792_HDR.jpg
  14. lookfar

    lookfar from the land of OZ Supporter

    Joined:
    Feb 13, 2011
    Oddometer:
    1,439
    Location:
    D'aguilar
    I'd replace that rocker if it were mine.

    Is it metallic alloy or metallic steel? Was there a small alloy dowel in either the oil pump or the right side cover when you opened it up? It would have had an o-ring around it.
    Thinking if the munched up bit is alloy, that could be where it came from. They are notorious for dropping out on assembly.
  15. Thebusdweller

    Thebusdweller Been here awhile

    Joined:
    Nov 23, 2012
    Oddometer:
    177
    Location:
    Nevada
    Kinda looks like a piece of bearing cage
  16. MattLikeyBikey

    MattLikeyBikey Been here awhile

    Joined:
    Nov 8, 2018
    Oddometer:
    561
    Location:
    So Cal
    Frame reinforcement - what is the latest and greatest in frame reinforcement for the XR600R? Does the SW Motech for XR650L work? Any other currently available products out there? I hear there were some before like Dirtbagz (?) that are no longer in biz.

    This is to reinfrace the rear part of the frame - for either adding bags or if one happens to be a larger individual :-)

    Thanks.
  17. Ron50

    Ron50 Long timer

    Joined:
    Oct 12, 2008
    Oddometer:
    3,318
    Location:
    Canberra
    My solution was just to find a welder I had confidence in to go over all the cracks and/or weak points with gussets.
    MattLikeyBikey likes this.
  18. msteward

    msteward Long timer

    Joined:
    Sep 14, 2015
    Oddometer:
    1,265
    Location:
    Spanish Fork, Utah
    Maybe straighten that out a bit and it might be easier to identify. Color of it makes it look like part of a lock plate of sorts.
  19. NMTrailboss

    NMTrailboss Team Dead End

    Joined:
    Mar 1, 2008
    Oddometer:
    9,059
    Location:
    Albuquerque, NM
    @mcma111 ... do you know any companies rebuilding newer XR600R crankshafts since replacements are no longer available from AHM? Any good rod kits out there still you would recommend?
    My '99 has a pretty loud knocking at mid-to-upper rpm's only after it is up to full operating temperature (20+ minutes of riding). Pretty quiet when first fired up and sounds normal otherwise. :cry
  20. Thebusdweller

    Thebusdweller Been here awhile

    Joined:
    Nov 23, 2012
    Oddometer:
    177
    Location:
    Nevada
    Steve uses Engine Dynamics the last I knew. Pro-x rods work well, ebay for 120 or so.
    NMTrailboss likes this.