XR650R Thread!

Discussion in 'Thumpers' started by JustinT, Nov 24, 2008.

  1. Cpt. Ron

    Cpt. Ron Advrider #128

    Joined:
    Jul 9, 2001
    Oddometer:
    3,350
    Location:
    Sacramento, CA
    Maybe the bigger question is, has anyone who HASN'T done a piston change (from OEM) had this happen? Which then leads to, why change to a lighter piston? Being an engineer, I appreciate the idea for reducing the reciprocating mass: quicker acceleration, less stress on attached members etc....For stuff like supermoto I get it. The littlest advantage can make a big difference.

    But I haven't been spanked by a modified BRP nor a stock one (stock meaning un-corked here) in the type of riding I do. Within the confines of the OEM covers on my bike, it's all stock. I've ridden with plenty of other BRP riders, and we all have our strengths and weaknesses. None of us have ever thought that the power of the bike held us back (suspension not withstanding....). The stock power plant leaves most mortals going "Holyyyyy Shittttttt" when they twist the throttle. The big differences seem to come in the tuning and rideability of the bike. If it doesn't work, no amount of power will save you. In my mind, it's the total package that matters.

    For my dual sport riding and occasional cross-country race, as well as the Kings of the West Rally, the stock internals of the motor work for me. They get me to the beginning AND the end of the event. About the only thing I'd consider changing from OEM is the intake valves for more longevity.

    But hey, that's just me.
  2. KYLEISCOOL

    KYLEISCOOL Who

    Joined:
    Dec 13, 2010
    Oddometer:
    144
    Location:
    So. Cal. U.S.A
    ^^^ +10 with you Ron. I totally concur and the thoughts of having to push my bike from places I go... No thanks. Longevity & Reliability is my main key in a bike. Hence why im sticking with the piggy not going to the more modern "race" type bikes. I can adjust my valves in the middle of BFE in a half hour and be on my way again if need be. :deal
  3. bill pierce

    bill pierce I don't wana pickle

    Joined:
    Mar 17, 2007
    Oddometer:
    741
    Location:
    Rockford, Wa
    What. Kind of life span are you guys getting out of a set of valves??
  4. Cpt. Ron

    Cpt. Ron Advrider #128

    Joined:
    Jul 9, 2001
    Oddometer:
    3,350
    Location:
    Sacramento, CA
    I don't keep track of miles very well, so I can't give you a definite answer. My bike was original when I got it used in early '06. About four years ago, I did a top end, replacing the rings, valves and guides (the exhausts look fine, by the way). Everything else was well within tolerance. It's been going strong ever since. I've done two Kings of the West Rallys (roughly 1,000 miles each), the Virginia City Grand Prix a couple of times, and quite a few dualsport rides in the Mendocino National Forest with only a couple of valve adjustments and oil changes.
  5. slogger

    slogger Been here awhile

    Joined:
    Nov 18, 2005
    Oddometer:
    656
    I've got about 15k out of my intakes(on two 650's). At about this point, my intakes would need adjustment ever 300-400 miles. Prior to this, it was ever 900-1200 miles. Also, these are all dirt miles but not super dusty. My air box always has dust in it no matter what I do.
  6. KonaTheHusky

    KonaTheHusky Adventurer

    Joined:
    Feb 7, 2013
    Oddometer:
    70
    Location:
    Somewhere on the West Coast
    My pig is dying on me in death valley. I'm at a small camp ground in panamint springs using the interwebs.

    My pig will kick over, run with no lack of power, then in a few miles starts to lug as if she isn't gettin gas. Eventually dies, but will kick over again after a few minutes if she's feeling nice. Then repeats. Exhaust sputters and pops a bit louder than normal when engine braking, but that could be me misremembering what's normal. She did this a couple times about 700 miles ago, but ran seafoam through two tanks and she quit the shenanigans.

    Camped in death valley last night and did the following: removed and disassembled petcock, there were a few burrs on the inner rubber gasket, but cleaned that up and flipped the gasket over so the good side is against the petcock lever. Disassembled/reassembled carb, nothing amiss. Adjusted valve clearances to spec, but did not take off crank cover to ensure exact TDC, so could be a little off. Repacked muffler. Checked, but did not clean, air filter. Also, cursed a bit.

    My theory: carb float needs replaced, and/or a swift kick in the ass.

    Ideas?
  7. RideFreak

    RideFreak Torque Junkie

    Joined:
    Apr 17, 2009
    Oddometer:
    6,537
    Location:
    Out in the NM Dez somewhere
    Looks like you did the obvious. Carb floats usally don't go bad, infact it's really rare and easy enough to check. They also wouldn't cause that symptom, the carb would be getting too much fuel if they were bad. To me it sounds like fuel is trickling into the carb and demand isn't keeping up with flow. As a test, run it, as it stats getting ready to die, flip on the choke, that will pull a bit more of the remaining fuel out of the carb. If you do that and it will run a short while longer then it's running out of gas. Cause can be up at the petcock (easy to check) or in the float area, Pull the fuel line, turn on the gas, see if you have good flow out of the tank. If that's ok it's possibly something is blocking the inlet screen at the float valve or the floats are hung in the upward (almost closed) position but even that should cause some leakage out the overflow. If the floats were bad (ie: they don't float :lol3) the fuel wouldn't shut off in the carb and it'd be pissin all over the ground. If you narrow it to the carb, I'd pull it and give it a good inspection, look to make sure the float assy isn't bent and that you can blow freely through the fuel line with the floats hanging. (float valve open). Shake the carb once it's together before you put it on the bike, you'll hear the floats bouncing up and down confirming that they aren't in a bind causing them not to work correctly. Check your gas cap vent too, that can cause the same thing, if you got one of those little check valve things on your gas cap, throw it away and replace with a piece of fuel line, they're junk and cause as many problems as they solve (I'd do this check first since it's easiest).

    Good luck and have a great ride, we expect some pictures when you return.
  8. RideFreak

    RideFreak Torque Junkie

    Joined:
    Apr 17, 2009
    Oddometer:
    6,537
    Location:
    Out in the NM Dez somewhere
    That's a big pilot jet, What's your fuel mileage? Is there some modification that allowing in (allot) more air? 68s seems to be the preferred size for sealevel. Asking because some folks don't realize, the metering passage in a pilot jet will slowly get smaller as the crappy fuels we get dries out. It forms a microscopic layer that will change the jet size over time, in the main jet it's impact is minimal but it can be significant in a pilot jet. If your mileage is reasonable than this is probably whats occurred, if it's crappy then the jet is allowing all the fuel into the motor.
  9. bill pierce

    bill pierce I don't wana pickle

    Joined:
    Mar 17, 2007
    Oddometer:
    741
    Location:
    Rockford, Wa
    Thanks, I adjusted my intakes about 500 miles ago when I bought the bike. Looks like they need it again already. Most bikes I have owned would do at least 3k between adjustments.:huh
  10. KonaTheHusky

    KonaTheHusky Adventurer

    Joined:
    Feb 7, 2013
    Oddometer:
    70
    Location:
    Somewhere on the West Coast
    I knew I didn't like that gas cap. Popped off the valve and drilled out the mini ping pong ball in there, breathes really well now. Went up the hill without it dying, but it was studdering and did die on the way down the hill. I think the float is sticking. Since I took it apart last night to no avail and have no carb cleaner with me, I'm gunna get the bike towed to ridgecrest in the mornin.

    Probably pick up a full carb rebuild kit for it.

    Thanks for the help.
  11. FlyGuy

    FlyGuy MachineHead

    Joined:
    Oct 18, 2005
    Oddometer:
    172
    Location:
    Middle of Highway 1 California
    RF
    I am happy I had the ross piston for 14,000 miles no complaints here.
    No warranty necessary
    it was a forged piston and it failed where you would expect.
    It could be developed further, but it is int worth the time for ross
    After seeing the wossner it was an easy decision. I am Not saying it will go further than 14,000 miles, But I am betting my money it will. $179 to my door
  12. FlyGuy

    FlyGuy MachineHead

    Joined:
    Oct 18, 2005
    Oddometer:
    172
    Location:
    Middle of Highway 1 California
    The XR650r is used in so many ways that it might be good to know how the bike is used
    The XR is my daily rider, this includes freeway riding as well,
    I ride a happy 72 mph at 47?? rpm for long distances. (off a calibrated vapor)
    I weigh 250 lb 300 lb when packing gear
    550-600 lb gross weight range
    my bikes are geared 16/40
    I have 2 XR650s and one is stock (uncorked and TM40)and the other bike (the one with the cracked piston) had
    advanced timing 3 extra degrees
    11 to 1 light weight piston (ross)
    blended ports (no porting just seat blend to wall)
    and a current big guns modded to go on a old wihte brothers E series muffler.

    OK i agree with you that the stock XR is more durable as is
    But the few mods the modded one had, Made a nice difference, I has more grunt and revs quicker
    smoother at the same power settings
    and Just easier to go faster

    In the mean time I ram riding the stocker bike and rebuilding other
    There are other issues with the motor I should point out later
    Happily riding the stocker But dreaming about the rebuilt Model
    [​IMG]
  13. FlyGuy

    FlyGuy MachineHead

    Joined:
    Oct 18, 2005
    Oddometer:
    172
    Location:
    Middle of Highway 1 California
    Ill try to get some pictures if I get time.
    But I have Kibbles Black diamond valves and have allot of mileage on stock valves to form an opinion
    Black diamond intake valves are an improvement over stock
    I have 14,000 mi on black diamond intakes with inital and one other adjustment near 12,000 they show near no wear
    As for Exhaust valves I believe the stock EX valve are better than the black diamonds from my wear analyses.
    Idd like to know if others are trying other types of valves?"
  14. bill pierce

    bill pierce I don't wana pickle

    Joined:
    Mar 17, 2007
    Oddometer:
    741
    Location:
    Rockford, Wa
    Thanks for your input guys. I'll just check them every 300-500 miles thru the summer, and then pull the head this winter. I'll upgrade to kibbies on the intakes then.
  15. slickwill

    slickwill Exhiled

    Joined:
    Dec 31, 2011
    Oddometer:
    209
    Location:
    Ohio
    Another yes.

    Sent from my DROIDX using Tapatalk 2
  16. FlyGuy

    FlyGuy MachineHead

    Joined:
    Oct 18, 2005
    Oddometer:
    172
    Location:
    Middle of Highway 1 California
    Valve pictures
    These valves have similar time on them, But I am suspecting the black diamonds have harder use?

    Black diamond intake on left with a known 14,000 mi, stock on the right Time unknown
    [​IMG]

    On the exhaust the black diamonds (left) have deeper Pitts in them
    the stockers could be re faced, but I really don't recommend that
    So I would give a slight advantage to the stock exhaust valve? (right)
    [​IMG]
  17. KonaTheHusky

    KonaTheHusky Adventurer

    Joined:
    Feb 7, 2013
    Oddometer:
    70
    Location:
    Somewhere on the West Coast
    Siphoned out some gas once I got to town (shoulda thought of this earlier) and found a good amount of water settling to the bottom...drained half the tank then refilled and added a gas treatment. She ran fine at full throttle from ridgecrest to mission viejo. She seems to sputter, pop, and lug a little when I'm maintaining speed (ie not accelerating) around or 2000rpm, but not when I accelerate hard through that range, or cruise on the 2500rpm range. Wonder if she's still fighting through the last of the bad fuel or if my jetting is now way off. Or both. I've got a 180main, forget the low flow, but its got an 's' in the size, and my needle is 2nd notch from the top. I'm gunna check out the carb and such tmrw. Any ideas on if I'm jetted right or not?
  18. RideFreak

    RideFreak Torque Junkie

    Joined:
    Apr 17, 2009
    Oddometer:
    6,537
    Location:
    Out in the NM Dez somewhere
    If it ran good at the start of te trip the jetting is probably ok, and XR is pretty forgivng when it comes to it's jetting. Probably need to drain the carb a few times, if you only drained half, then chances are you're still dealing with a water issue, just not as bad.
  19. KonaTheHusky

    KonaTheHusky Adventurer

    Joined:
    Feb 7, 2013
    Oddometer:
    70
    Location:
    Somewhere on the West Coast
    Yup. Makes sense. I'll get rid of all the gas, and pull the carb bowl for a good wipe down. Thanks!
  20. larryboy

    larryboy Chopper Rider

    Joined:
    Jan 9, 2005
    Oddometer:
    15,374
    Location:
    On a set of 50,000 mile tires.

    Sounds super fat and a fouled plug. Drop the needle...edit, just read again, second from the top is how you're compensating for the huge main...leave the needle where it's at, 165 main, new plug and make sure the jam nut on the emulsifier tube is tight with the tube fully seated.