Rear pulley: it moves! - BMW F800 Riders Forum & Registry



Remove this advertisement by REGISTERING.

Results 1 to 19 of 19
  1. #1
    Points: 944, Level: 17

    Joined
    Jul 2018
    Online
    10-07-19
    Posts
    11 / 0 / 0 / 0
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Hello,

    first THANK YOU for being here !
    I purchased -a full year ago- from a bike shop a 2006 800 st. ( 50.000 kms )
    All checks were done, so I drove happily for about 8000 kms.
    Last week I tightened the drive belt, because after a 300 kms on the highway it was loose.
    Well, now, after another 300 kms normal road use, If I pull the back pulley, it moves !!!
    Slightly, of course, about a millimeter, or so.
    Not the whole wheel assembly, just the big pulley.
    It moves a little, It can be felt moving it with the fingers. The nuts are tightened, nothing else moves.

    Do you think I have to expect somethin' ???

    Thank you so much,

    GREETINGS FROM MONT BLANC

  2. Remove Advertisements
    F800Riders.org
    Advertisements
     

  3. #2
    Points: 8,182, Level: 63

    Location
    Berkshire, UK
    Joined
    Jun 2013
    Online
    6 Hours Ago
    Posts
    621 / 0 / 2 / 32
    it's probably the rubber drive that is allowing it some movement. if it is so small I would not worry about it too much, so long as its not the whole eccentric hub moving.
    BMW F800ST, 2010, Black, Fuzeblock, Sat Nav, BMW Tank Bag, Givi Touring Screen, 

  4. #3
    Points: 944, Level: 17

    Joined
    Jul 2018
    Online
    10-07-19
    Posts
    11 / 0 / 0 / 0
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Quote Originally Posted by DJ123 View Post
    it's probably the rubber drive that is allowing it some movement. if it is so small I would not worry about it too much, so long as its not the whole eccentric hub moving.
    You think it's ok then.
    Good to hear that !
    Well, I wondered if it was the starting point of something known.
    I checked again the wheel and yes, it is tight.
    I am about to put the bike into " winter mode ", so I will add some more checks on it, later.

    So, thank you for help !

  5. Remove Advertisements
    F800Riders.org
    Advertisements
     

  6. #4
    Runmyownlife's Avatar
    Points: 13,377, Level: 79

    Real Name
    Andrew
    Location
    Calgary, Alberta
    Joined
    Feb 2017
    Online
    5 Hours Ago
    Posts
    878 / 0 / 0 / 0
    Motorcycle
    '08 F800 ST
    Motorcycle
    '08 F800 ST
    300 kms on the highway it was loose.
    A few questions to clarify why you thought it was loose and how did you determine the new, tighter position? A belt that is too tight will make quick work of the rear bearing. A classic error is to adjust without considering the rear wheel and weight is off the ground - the belt gets a whole lot tighter with a rider in the seat.

    In normal belt adjustment the rear pulley is not loosened or removed. Only the eccentric via the three adjustment screws is effected.

    The rubber plugs inside the rear assembly will not produce lateral play. Regrettably, this is a common misconception.
    These plugs reduce the shock of acceleration and only produce play in line with the belt.

    At one millimetre of play I would suggest you ride on, monitor n regularly and re-evaluate belt tension (err on the side of looser - the downside risk is much less costly.)
    Concrete remains undefeated. 

  7. #5
    Points: 944, Level: 17

    Joined
    Jul 2018
    Online
    10-07-19
    Posts
    11 / 0 / 0 / 0
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Thank You,

    To answer your question, after my highway - high speed - drive, I was parking the bike into the garage, when I noticed that the belt, before well fitted into the left side of the pulley, was now some millimeters outwards on the right side.
    I touched it, and it was really slappier than before.
    And "softer", in some way.
    So, without considering weight off the ground - only checked the dot on the pulley - I proceeded with the three adjustment screws and the sub-arm hole, as per Manual.
    I read the 45 degrees test on the belt, and it seemed rather easy to do, while the whole thing seemed firmer than before.
    So after a couple of days I made a quick tour in the mountains, and everything worked well.
    Back home, I was cleaning the arm and belt from dirt, and....oopss !! THAT axial play.
    I took the pulley with both hands and yes, it moved.
    It was not present on the bike before.
    Make sure I'll test it each time I take a ride !
    And I'm wondering if it's worth to disassemble the whole thing for a full transmission control...

  8. #6
    ccramerusc's Avatar
    Points: 7,557, Level: 61

    Real Name
    Cramer
    Location
    Milwaukee, WI
    Joined
    Jun 2013
    Online
    8 Hours Ago
    Posts
    573 / 0 / 0 / 6
    Motorcycle
    '08 F800ST
    I just replaced mine for the exact reason and symptoms you mention. My wheel bearings are good, but I could wobble the pulIey easily. I took mine apart only to realize one of my rubber cush bumpers was deformed, and also found that the bearing inside the pulley was loose. I couldn't get the c clip washer out to remove the bearing, so I just bought a used pulley from eBay. It went on easily and my wobble is gone with the belt sitting right against the inside edge of the pulley now.

    Getting the pulley back cover to come off the front and expose the cush bumpers was not easy. But with a perfectly sized piece of oak and a sledge hammer, it will come apart. A little PB blaster also helped. The manual mentions using a hydrolic press. Those bumpers are $28 a piece (there's 4 of them) and the bearing is $128. I bought the whole thing used from eBay for $60.

    Sent from my SAMSUNG-SM-G891A using Tapatalk
    08' F800ST- side panniers & Shad SH45 top case, Russell Day Long seat, MRA Vario Windscreen, SW Motech crash bars, ZTechnik exhaust, PC-8 fuseblock, Stebel Nautilus horn, Throttlemeister throttle lock, SW Motech handlebar risers, LED fog lights, highway pegs 

  9. Likestvbilld liked this post
  10. #7
    Points: 944, Level: 17

    Joined
    Jul 2018
    Online
    10-07-19
    Posts
    11 / 0 / 0 / 0
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Hello,

    here the news:
    wife being happy today, I was allowed to enter garage.

    I simply got out the circlip of the wheel axis, and....
    you wouldn't believe that, he 45 mm bolt could be unmounted by the hand !
    I was really dismayed.
    But yet, the circlip hole is one and it had to be in that position, normally, followed by its bolt.
    So I proceeded to put out the rear pulley, since the belt could be easily removed from it.
    The whole thing was full of rusted crap, probably very old special grease become solid.. it disintegrated under my hands.
    So, I kept to clean all the components, which took me about half an hour.
    I didn't touch anything else, and mounted again the four components.
    I put some loctite on the big bolt and tightened in the best way I could, with a weight on the rear brake pedal, then I set the outer circlip in its position.
    I' ll wait till tomorrow to test that fix, it seemed to me it was not moving at all.

  11. LikesSuperduper, Runmyownlife liked this post
  12. #8
    ccramerusc's Avatar
    Points: 7,557, Level: 61

    Real Name
    Cramer
    Location
    Milwaukee, WI
    Joined
    Jun 2013
    Online
    8 Hours Ago
    Posts
    573 / 0 / 0 / 6
    Motorcycle
    '08 F800ST
    Hopefully that's all it was. Glad that little clip wire was there! In case you want to be sure, the big pulley nut is supposed to be torqued to 160Nm. I was able to get mine that tight while holding the rear brake down as you described.

    Sent from my SAMSUNG-SM-G891A using Tapatalk
    08' F800ST- side panniers & Shad SH45 top case, Russell Day Long seat, MRA Vario Windscreen, SW Motech crash bars, ZTechnik exhaust, PC-8 fuseblock, Stebel Nautilus horn, Throttlemeister throttle lock, SW Motech handlebar risers, LED fog lights, highway pegs 

  13. #9
    Points: 944, Level: 17

    Joined
    Jul 2018
    Online
    10-07-19
    Posts
    11 / 0 / 0 / 0
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Motorcycle
    '06 F800ST
    Thank You ccramerusc,

    I really don't know how this could have happened..it scared me quite a lot.

    I' ll do a little trip through the mountain this afternoon, to control belt, pulley & Co.
    Then I will unscrew and rescrew the big one at the right torque.

    GREETINGS FROM MONT BLANC

  14. #10
    tvbilld's Avatar
    Points: 5,792, Level: 52

    Real Name
    Bill Darter
    Location
    Springfield Missouri
    Joined
    Nov 2012
    Online
    2 Hours Ago
    Posts
    114 / 0 / 0 / 13
    Motorcycle
    '08 F800 ST
    Also had to replace my rear belt wheel a couple of weeks ago. Got a used one from E-bay for $49.95. Copy of my previous post. Just discovered what the clicking noise was when i was pushing my F800ST in the garage . got to looking & the belt was tracking hanging over the edge of the belt wheel about 1/16 inch. grabbed hold of the belt wheel and it would rock back & forth with a clicking noise. I was not happy. So i pulled the Belt Wheel off to dis assemble it & discovered the Drive Dog didn't want to come out of the Wheel assembly. After i finally got it out this is what i found. ( if the link to the Google photos works ). https://photos.app.goo.gl/WRbfsDHm6yugjpEZ9 Got a used Belt wheel assembly O/O from E-Bay for $49.00 Hope it's better than the one i Have!! Could have ordered new drive dog,rubber Bumpers & Bearing for about $455.00 & just repaired my Belt Wheel . but hoping to get by with a used one. & the used one was much better.

  15. Likesccramerusc, Runmyownlife liked this post
  16. #11
    Titlerider's Avatar
    Points: 3,987, Level: 42

    Real Name
    Ethan
    Location
    Grand Rapids, MI
    Joined
    Jun 2015
    Online
    2 Weeks Ago
    Posts
    119 / 0 / 0 / 0
    Motorcycle
    '07 F800ST
    This past summer I noticed that my drive belt was slowly moving away from the hub and towards the outer edge of the drive wheel. It was very gradual. I kept riding. Then one day, a couple of months later, I started to ride out of my driveway and heard a horrible noise. I got off the bike and noticed that the belt was hanging over the outside edge of the drive wheel and was grinding the belt guard. That was bizarre, because on the previous weekend, I had been on a 250 mile trip. The dealer diagnosed multiple problems including that the cush rubbers were disintegrated, the bearing(s) was way out of round and there was no way to repair any of it. Of course, the price for new was over $1200 US. So the parts guy and I went online and we found an entire rear swing arm and drive wheel assembly from an F 800 GT that had suffered from catastrophic engine failure at 3,000 miles. I bought the rear end assembly for $350 and the dealer put it all back together again. He’d never seen a rear end failure like that. By the way, this was at about 69,000 miles.

  17. #12
    Daboo's Avatar
    Points: 40,639, Level: 100

    Real Name
    Chris
    Location
    Seattle, WA
    Joined
    Jun 2014
    Online
    6 Hours Ago
    Posts
    4,062 / 0 / 9 / 3
    Motorcycle
    '14 F800 GT
    That's precisely why I leave mine alone. At 49,000 miles, I still have the first belt installed. Other than the lettering fading over time, it looks great. I'll keep inspecting it, and when out of the local area, I'll carry the new belt with me.

    The belt apparently is adjusted just right. My Dad used to tell me that the reason we didn't take the family car apart on the weekend and then put it back together, was that in the process, we'd inevitably break something. And we didn't have the money to fix what wasn't broken before.

    I used to think the reason it was lasting so long was because I was easy on the throttle. Well...not really. I have wound the bike up into the 6-8000 rpm range for hours and days on end, and used primarily engine braking...and the belt looks like the little old lady from Pasadena rode it instead.

    When I did take the original belt off once (to prove I could do it on the side of the road), I put it next to the new belt. There might've been some difference in the belt lengths, but I didn't see it. When I do eventually change the belt, I'm going to pull the old belt off and put the new belt on...and not change anything for the belt adjustment.

    If it ain't broke, don't fix it.

    Chris
    Elnathan - 2014 BMW F800GT
    IBA# 49894 True Rounder = 0-20's - Rounder -- to -- 100's+ Red Hot Rounder

    John 14:6 

  18. Likesnotacop liked this post
  19. #13
    BoxerBits's Avatar
    Points: 959, Level: 17

    Real Name
    Nigel
    Location
    St. Neots, Cambs.
    Joined
    Apr 2019
    Online
    5 Hours Ago
    Posts
    145 / 0 / 0 / 0
    Quote Originally Posted by Daboo View Post
    ...
    When I did take the original belt off once (to prove I could do it on the side of the road), I put it next to the new belt. There might've been some difference in the belt lengths, but I didn't see it.
    ...
    Local engineering friend of mine who used to work for Gates, tells me that these belts don't get longer with use. It's just that the cumulative wear in each tooth results in the need for belt adjustment to take up the slack.




    Sent from my moto g(6) play using Tapatalk

  20. #14
    notacop is offline The original Schwartz Wald Troll
    Points: 48,126, Level: 100

    Location
    SoCalif. near Pasadena
    Joined
    Sep 2007
    Online
    2 Hours Ago
    Posts
    12,940 / 8 / 110 / 2177
    Motorcycle
    '08 F800 ST
    Motorcycle
    '04 DL-650A V-Strom
    Motorcycle
    '13 G650GS (Single)
    When I got my 08 ST, the salesman was telling another customer that the belt was factory adjusted and wouldn't need any attention for the life of the bike. Then the 24K interval thing became prevalent.
    Like Daboo, leave the thing along and don't let the dealer "adjust" things for you. The belt on the ST at 57K miles was still good. Then I met a deer.

  21. #15
    BoxerBits's Avatar
    Points: 959, Level: 17

    Real Name
    Nigel
    Location
    St. Neots, Cambs.
    Joined
    Apr 2019
    Online
    5 Hours Ago
    Posts
    145 / 0 / 0 / 0
    Quote Originally Posted by notacop View Post
    ...
    Like Daboo, leave the thing along and don't let the dealer "adjust" things for you.
    ...
    Agree, if you don't know what you're doing or have little faith in your dealership then leave the thing alone. Be aware however that it has a life span like everything else.

    Different matter if you know what your doing though.



    Sent from my moto g(6) play using Tapatalk

  22. #16
    Melbourne, Australia IanA is offline F800Riders.org Supporter
    IanA's Avatar
    Points: 17,403, Level: 91

    Real Name
    Ian
    Location
    Melbourne, Australia
    Joined
    Jun 2012
    Online
    1 Day Ago
    Posts
    1,355 / 12 / 326 / 820
    Ethan, just curious to know whether you replaced the whole swingarm and drive assembly on your ST with one from a later GT, or just the bearings and drive wheel assembly. As I understand it, the GT swing arm is some 20mm longer than the ST, hence the different belt spec( and an excuse to charge way more for a GT belt).
    Just wondering, as I have a few bits from my old ST around and not sure what might be useful to keep for spares for my new GT.
    Cheers from Downunder.

  23. #17
    Titlerider's Avatar
    Points: 3,987, Level: 42

    Real Name
    Ethan
    Location
    Grand Rapids, MI
    Joined
    Jun 2015
    Online
    2 Weeks Ago
    Posts
    119 / 0 / 0 / 0
    Motorcycle
    '07 F800ST
    Ian, just got back to the site. Just the bearings and drive wheel assembly. The dealer has the GT swing arm in the shop somewhere. I doubt that the swing arm from the GT will be used ever. The dealer didn’t sell many GTs.

  24. #18
    Points: 318, Level: 6

    Joined
    Sep 2019
    Online
    01-20-20
    Posts
    25 / 0 / 0 / 0
    You uses LOCTITE??? What color??? I sure hope you never have to remove the rear wheel nut again......

  25. #19
    Randyjaco's Avatar
    Points: 1,112, Level: 19

    Real Name
    Randy
    Location
    Friendswood TX
    Joined
    Jun 2019
    Online
    27 Minutes Ago
    Posts
    60 / 0 / 0 / 0
    It really doesn't matter. Heat up any Loctited fastener to @400 degrees and it's easily removed.
    Randy
    2010 F800ST 

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •