f650gs twin sprocket torque setting

Discussion in 'Parallel Universe' started by dsavage, Mar 21, 2009.

  1. dsavage

    dsavage Been here awhile

    Joined:
    Sep 21, 2007
    Oddometer:
    301
    Location:
    Waco, Texas
    I just received my 16 tooth front sprocket for my F650GS twin via FedEx today and would like to install it tomorrow. Does anyone know the proper torque is for this nut that holds the sprocket on the shaft?
    #1
  2. jdaniele

    jdaniele Long timer

    Joined:
    Oct 5, 2007
    Oddometer:
    1,003
    Location:
    Moved to the country. Hudson Valley
    Here ya go see bottom of page for spec

    27 71 000 ​
    Removing chainwheel

    – Remove rear wheel.​
    a ​
    ....................................................See Group 36

    • ​
    Remove chainwheel carrier (2) together with
    chainwheel (1) from rear wheel hub.

    • ​
    Remove screws (3) and remove the chainwheel.

    X ​
    Tightening torques:

    Chainwheel to carrier ................................... 21 Nm​
    27 71 000 ​
    Removing chain sprocket

    – Remove the chain.
    – Select first gear.​
    • ​
    Straighten the tabs of the locking washer on the
    central nut.

    • ​
    Remove the plug on the right side of the crankcase.

    • ​
    Hold crankshaft with Allen key (arrow).

    d ​
    Warning:

    Central nut (5) is secured with ​
    Loctite 243 and considerable
    torque is required to release it.

    • ​
    Unscrew central nut (5).

    • ​
    Remove the locking washer (4).

    • ​
    Use puller, BMWNo. 00 8 400, to pull the chainwheel
    off the mainshaft.

    • ​
    Installation is the reverse of the removal procedure:
    pay particular attention to the following.

    • ​
    Lightly coat the mainshaft with Optimoly MP 3

    before installing the chainwheel.​
    – The sprocket must be installed with the “EXT”
    marking on the outside.​
    • ​
    Install a new locking washer (4).

    • ​
    Clean threads of central nut and mainshaft, coat
    threads with
    Loctite 243 and install nut.

    • ​
    Bend up tab (arrow) of locking washer.

    X ​
    Tightening torques:

    Central nut on mainshaft
    (clean thread + Loctite 243)........................ 140 Nm​
    E360030​
    2
    3 1​
    E270040​
    EXT​
    E270030
    #2
  3. dsavage

    dsavage Been here awhile

    Joined:
    Sep 21, 2007
    Oddometer:
    301
    Location:
    Waco, Texas
    Thanks. Doesn't look as easy as I thought. Figured I'd just loosen the rear, drop the chain and pull the sprocket. Didn't figure I'd need any special tools but afterall it is a BMW...should have known.
    #3
  4. jdaniele

    jdaniele Long timer

    Joined:
    Oct 5, 2007
    Oddometer:
    1,003
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    Moved to the country. Hudson Valley
    You don't need any special tool the front sprocket will just wiggle off.

    If you have access to an imapct gun and a 30mm socket removal will be easy.

    You can use the lock washer two times it has two bend points I strongly suggest clean loctite and proper torque on the nut. The sprocket only has one correct direction but will fit both ways look carfully before you remove it self explanatory if you observant.
    #4
  5. dsavage

    dsavage Been here awhile

    Joined:
    Sep 21, 2007
    Oddometer:
    301
    Location:
    Waco, Texas
    Have a 30mm socket and access to an impact wrench. Thanks. Sounds like all I need is the proper locktite. Think I'll go ahead and change this out tomorrow.......the 650 needs more low end and from what I read it doesn't negatively impact the gas mileage. I appreciate your help. Advrider is invaluable to me.
    #5
  6. jdaniele

    jdaniele Long timer

    Joined:
    Oct 5, 2007
    Oddometer:
    1,003
    Location:
    Moved to the country. Hudson Valley
    The 16 tooth is stock for some more bottom end you need the 15 tooth. It is a nice mod and the bike will still be fine aT highway speeds.
    #6
  7. jessehere

    jessehere Ridin'

    Joined:
    Apr 6, 2005
    Oddometer:
    877
    Location:
    Jersey(EXIT 10)
    Info is for wrong bike!! he asked for the twin
    #7
  8. jdaniele

    jdaniele Long timer

    Joined:
    Oct 5, 2007
    Oddometer:
    1,003
    Location:
    Moved to the country. Hudson Valley
    your right I am thinking twin spark not the new bike

    I PM"D HIM
    #8
  9. dsavage

    dsavage Been here awhile

    Joined:
    Sep 21, 2007
    Oddometer:
    301
    Location:
    Waco, Texas
    That's the problem with BMW not giving the 650 twin a different name. It's too easy to confuse with the single. Now that we've got that sorted out, is the torque setting the same or is it different on the twin?
    #9
  10. MBronskill

    MBronskill MedPhys

    Joined:
    Sep 24, 2007
    Oddometer:
    40
    Location:
    Toronto, Canada
    The correct torque for the 650 twin sprocket bolt (M10x1.5x35) is 50 Nm. The 16-tooth sprocket is a nice improvement for me. Much less clutch slipping around town and not any buzzier at higher rpm on the highway.

    The old sprocket came off easily without a puller although the BMW instructions suggest that one is necessary. Just be sure to put the new sprocket back in the same orientation.

    Mike
    #10
  11. dsavage

    dsavage Been here awhile

    Joined:
    Sep 21, 2007
    Oddometer:
    301
    Location:
    Waco, Texas
    Changed the sprocket and thanks for the torque setting. The rear axle setting is in the book at 100nm. The difference in the 17 and 16 is amazing. Lots more low end. They should have done this at the factory. The job took about 30 minutes and I would recommend this to everyone with a 650 twin.
    #11