1. eNewsletter Sign Up

the DR650 thread

Discussion in 'Thumpers' started by sleepywombat, May 1, 2006.

  1. stoltzfii

    stoltzfii Been here awhile

    Joined:
    May 6, 2015
    Oddometer:
    473
    Location:
    Honey Brook, Pennsylvania
    I have a dr650 with a bad knock.

    Pulled my head, rings look ok, cylinder walls are ok, the right side of the piston at the top is really black, maybe from blow-by.
    But the valves look terrible. The intake valves are black and the exhaust valves are crazy white. Would this be from the engine running way too lean or from the blow-by? The valves were cleaned and lapped 1500 miles ago, so this all is very recent. I am burning through a lot of oil, 1 liter every 500 miles, but I can't get new rings in Chile, and I'm 250 miles from Ushuaia.

    Doesn't really explain the knocking. Unless it's a detonation issue. Any suggestions?



    [​IMG][​IMG][​IMG]
    TreasureState and Redfish Hunter like this.
  2. Ever Onward

    Ever Onward Older,Wiser, Smarter

    Joined:
    May 1, 2011
    Oddometer:
    6,765
    Location:
    Flying straight across the great divide



    You may not like my answer, but if it were me, I would be ridin in a truck that last 250 miles.
    Nogoodnamesleft and NC Rick like this.
  3. stoltzfii

    stoltzfii Been here awhile

    Joined:
    May 6, 2015
    Oddometer:
    473
    Location:
    Honey Brook, Pennsylvania
    That's what I'm planning on. I more just pulled it to see what the issue is and if I could fix it relatively easy I would, otherwise sell it for parts for cheap here in Punta Arenas
    TreasureState likes this.
  4. Redfish Hunter

    Redfish Hunter Long timer Supporter

    Joined:
    Jun 25, 2018
    Oddometer:
    1,045
    Location:
    Prairieville, Louisiana
    Why does it look like only the center spark plug is firing? Is that just how it looks in the picture?
    smilin jack and drmiller100 like this.
  5. Ever Onward

    Ever Onward Older,Wiser, Smarter

    Joined:
    May 1, 2011
    Oddometer:
    6,765
    Location:
    Flying straight across the great divide

    Good idea.

    With the look of your piston and the amount of oil its using, I would seriously think about shooting that donkey and putting it out of its misery.

    Sure, you can fix it. But there comes a time when it would just be alot better to switch to a better bike.

    Strip any special and expensive parts that are in great shape, and just move on to the next bike.
    NC Rick likes this.
  6. stoltzfii

    stoltzfii Been here awhile

    Joined:
    May 6, 2015
    Oddometer:
    473
    Location:
    Honey Brook, Pennsylvania
    Maybe, but I'm pretty sure they were both firing. Here are closer pictures.[​IMG][​IMG]
  7. Ever Onward

    Ever Onward Older,Wiser, Smarter

    Joined:
    May 1, 2011
    Oddometer:
    6,765
    Location:
    Flying straight across the great divide
    Outside plug looks mighty funky. Could be fouled out.

    You have alot of blowby past the rings. Im guessing you might have overheated the engine pretty bad, and cooked the rings. The rings will lose tension when roasted bad, then combustion can blow by. This cooks your oil, which wrecks the engine.

    Like Mongle mentions, its hard to diagnose from vid clip sounds, but you have issues no doubt. Sounds like it could be in the valve train even.

    Reguardless, its mighty loud, and losing a litre of oil every 500 miles means somethings really wrong. A bit odd your head isnt looking like a oil burn situation ?

    Oil leak elsewhere ? Whats the inside of the exhaust pipe look like ?
    TreasureState and NC Rick like this.
  8. stoltzfii

    stoltzfii Been here awhile

    Joined:
    May 6, 2015
    Oddometer:
    473
    Location:
    Honey Brook, Pennsylvania
    Inside of the exhaust pipe at the header end is white.

    I think the main issue (out of many problems) is connecting rod play. I can move the rod up and down on the crank and here a clank noise. This is way too much movement, I belive.

    Here's a video, but it doesn't show it too well.

    JagLite likes this.
  9. bobzilla

    bobzilla Dirty Old Man

    Joined:
    Apr 19, 2006
    Oddometer:
    1,207
    Location:
    Lost & Found again in the Great Basin
    yehaaa6 and NC Rick like this.
  10. StannisBaratheon

    StannisBaratheon Been here awhile

    Joined:
    Jun 28, 2017
    Oddometer:
    561
    Location:
    Dragon Stone
    Update from the machine shop: Cylinder is serviceable and is being honed to break the glaze on the walls. Valve guides were out of spec and need replacement. Valves are serviceable. Everything is being cleaned up while I wait for parts to be delivered.

    So definitely good news. I was hoping it was just worn seals, but worn guides are better than a worn cylinder. Will continue to update as things progress.
  11. procycle

    procycle Long timer

    Joined:
    Jun 7, 2007
    Oddometer:
    7,148
    Location:
    Center of the DualSport Adventure universe
    Any up-down play you can feel is WAY too much. It's all over for that motor.
  12. JagLite

    JagLite Long timer Supporter

    Joined:
    Jun 17, 2010
    Oddometer:
    8,276
    Location:
    Anchorage Alaska

    :hung :grim :pep

    Unfortunately, it looks like the end for that crank and rod.
    Anybody got a spare around there? :becca

    Of course not :dirtdog

    So, can you source any other used motor, from anything, that you can McGyver in there to get you the last 250 miles?
    Bicycle crank and pedals maybe?
    You just have to drag that DR to the end of the road!
  13. wee-twin

    wee-twin Been here awhile

    Joined:
    Sep 10, 2009
    Oddometer:
    468
    Location:
    Westchester County, N.Y.
    The question I have is what caused crank and connecting rod to become damaged?
  14. procycle

    procycle Long timer

    Joined:
    Jun 7, 2007
    Oddometer:
    7,148
    Location:
    Center of the DualSport Adventure universe
    Unfortunately, that bike had some bad recent history. My guess to what happened is the broken carb slide resulted in the motor having to be run very lean for quite a few miles. The lean running resulted in prolonged detonation which pounded flat spots in the rod bearing rollers.
    waterman28, ER70S-2, Anthiron and 8 others like this.
  15. NC Rick

    NC Rick Cogent Dynamics Inc

    Joined:
    Aug 31, 2007
    Oddometer:
    7,439
    Location:
    Asheville, NC
    It
    was very enjoyable and I can be a snob.
  16. NC Rick

    NC Rick Cogent Dynamics Inc

    Joined:
    Aug 31, 2007
    Oddometer:
    7,439
    Location:
    Asheville, NC
    An you leave the bike there? Often that can be difficult.

    Sorry that your bike is toast.
  17. procycle

    procycle Long timer

    Joined:
    Jun 7, 2007
    Oddometer:
    7,148
    Location:
    Center of the DualSport Adventure universe
    A moment of silence please.... for @stoltzfii 's DR650.

    A valiant motorcycle that gave all it had to give... and made the ultimate sacrifice.... in the name of adventure...
    waterman28, gbmaz, Hivernaut and 21 others like this.
  18. NC Rick

    NC Rick Cogent Dynamics Inc

    Joined:
    Aug 31, 2007
    Oddometer:
    7,439
    Location:
    Asheville, NC
    Moment of silence
  19. FR700

    FR700 Heckler ™©®℗

    Joined:
    May 4, 2007
    Oddometer:
    18,166
    Location:
    Your imagination.
  20. StannisBaratheon

    StannisBaratheon Been here awhile

    Joined:
    Jun 28, 2017
    Oddometer:
    561
    Location:
    Dragon Stone
    RIP in piece