Author Topic: Play in rear wheel and leaking of fluid  (Read 7646 times)

Offline Mavebrick

  • Motobrick Curious
  • Posts: 36
Play in rear wheel and leaking of fluid
« on: December 10, 2024, 09:10:33 AM »
Hi I have a fluid leaking which does not look like the final drive gear oil. I am not sure what it is exactly, does it look familiar to y’all? Seems yellow/green, very gooey and thick much more viscous than gear oil. I have already checked final drive gear oil level and its fine.

Also my rear wheel has a slight play. Is that a sign of bad rear splines or rear wheel bearing or both? What do y’all recommend i do? I rode some yesterday but should I stop riding on it and take apart rear splines to see what’s going on? Any of yall had this type of slight play in rear wheel and what steps did yall take to tackle it? Thank you, appreciate it.
  • Houston Texas
  • 1986 BMW K75C

Offline The Mighty Gryphon

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Re: Play in rear wheel and leaking of fluid
« Reply #1 on: December 10, 2024, 12:01:24 PM »
Could that fluid be coming from the shock?
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Mavebrick

  • Motobrick Curious
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Re: Play in rear wheel and leaking of fluid
« Reply #2 on: December 10, 2024, 01:33:56 PM »
I think you’re right! It looks like the rear shock after removing the saddle bags seems to be leaking from that shock. Is it toast and needs a new one or do folks typically rebuild these?
  • Houston Texas
  • 1986 BMW K75C

Offline Mavebrick

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Re: Play in rear wheel and leaking of fluid
« Reply #3 on: December 10, 2024, 02:20:13 PM »
The rear play seems to not be there when i have the rear brake pressed down but the play comes back when the rear brake is released. Does this narrow the cause in any way?
  • Houston Texas
  • 1986 BMW K75C

Offline Chaos

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Re: Play in rear wheel and leaking of fluid
« Reply #4 on: December 10, 2024, 02:25:42 PM »
by "play" do you mean in the same direction as the rotation or sideways?  Some rotational play is normal, sideways is not. 
  • sw ohio
1987 K75S    VIN 0231
Original owner, Original litter
200,000 miles (plus or minus) and 5 paint jobs
sold 6/23
2023 Ural 2WD sidecar (BMW's bastard step child)

Offline Mavebrick

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Re: Play in rear wheel and leaking of fluid
« Reply #5 on: December 10, 2024, 02:52:39 PM »
Sideways.when i hold it at the 9o clock or 12o clock position and yank it towards me it has noticeable play. I did this because on my shakedown ride yesterday after working on coolant and radiator fan johnny blanket etc i felt the back tire a little squirly/fishtailly very subtle but it was there. So i wanted to take a closer look at the rear wheel and seems like the shock is shot and some bearing is off. I dont know much about k bikes rear wheel bearing cos it doesnt seem conventional like my other bike
  • Houston Texas
  • 1986 BMW K75C

Offline Laitch

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Re: Play in rear wheel and leaking of fluid
« Reply #6 on: December 10, 2024, 03:56:24 PM »
Have the wheel bolts loosened? If not, one or both of the bearing assemblies indicated in the diagram are likely to be the source of this condition. Find information in BMW's K75/K100 2V service manual downloadable here and the Clymer or Haynes manuals.


  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline The Mighty Gryphon

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Re: Play in rear wheel and leaking of fluid
« Reply #7 on: December 10, 2024, 04:26:17 PM »
Some shocks are rebuildable and some aren't.  Can you post a photo of your shock?
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Mavebrick

  • Motobrick Curious
  • Posts: 36
Re: Play in rear wheel and leaking of fluid
« Reply #8 on: December 10, 2024, 06:49:13 PM »
This is a picture of my shock
  • Houston Texas
  • 1986 BMW K75C

Offline Mavebrick

  • Motobrick Curious
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Re: Play in rear wheel and leaking of fluid
« Reply #9 on: December 10, 2024, 06:52:10 PM »
I tried to “tighten” the lugnut and none of the lugnuts are really moving in the clockwise direction at all. I have narrowed the play as shown in the red arrow. When i move the tire away from me and towards me the gap narrows or widens in that gap.
  • Houston Texas
  • 1986 BMW K75C

Offline The Mighty Gryphon

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Re: Play in rear wheel and leaking of fluid
« Reply #10 on: December 11, 2024, 12:30:20 AM »
That's a Works Performance shock that you have.  They were pretty popular on the bricks back in the day.  I had two of them come through the garage on K75's.  I had one rebuilt by the factory just before they went out of business in 2017. 

I'm not sure you can still get parts.  There is a special tool to remove the end cap to get at the seal.  Unless you have experience rebuilding shocks I would recommend getting a new replacement shock.  I have used YSS shocks, and they are very good for the money.
  • In my garage in Marilla, NY
  • '91K100RS White/Blue
Current:
'91 K100RS16V "Moby Brick Too"

Past:
'94 K75RT "Ilsa, She Wolf of the SS"
'92 K100RS16V "Moby Brick" (RIP, deceased in a vehicular assault)
'94 K75S Special Edition Dakar Yellow "Cheetos"
'89 K100RS Special Edition "Special Ed"

Offline Laitch

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Re: Play in rear wheel and leaking of fluid
« Reply #11 on: December 11, 2024, 10:49:11 AM »
. . .. I have narrowed the play as shown in the red arrow. When i move the tire away from me and towards me the gap narrows or widens in that gap.
Read this thread to determine how its circumstances apply to yours. I believe you'll need to start disassembling the final drive to locate the problem.
  • Along the Ridley in Vermont.
  • 1995 K75 89,000 miles

Offline Mavebrick

  • Motobrick Curious
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Re: Play in rear wheel and leaking of fluid
« Reply #12 on: December 11, 2024, 02:41:24 PM »
Thank you Laitch. Ordered a used final draft from eBay with free 30days return and supposedly has been tested to be in good condition. I know it’s the lazy way but I don’t want to overestimate my mechanical acumen.

Now am shopping for a new suspension as well.Yss was a recommendation please feel free to recommend others if you had good experiences
  • Houston Texas
  • 1986 BMW K75C

Offline Past-my-Prime

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  • All of us are better when we're loved.
Re: Play in rear wheel and leaking of fluid
« Reply #13 on: December 11, 2024, 10:21:51 PM »
For some crazy reason, I went with a Wilbers shock (from Germany) It cost about 800 Euros and something. Plus delivery. It did improve the ride on the motorbike and I guess now I’m committed to my Brick!

I think I must have been reading reviews / come into some unexpected money / thought “I need this”.

Not that I’m suggesting that any other aftermarket shock is a bad choice.
  • North Shore of Lake Superior (in my garage)
  • BRICK: 1989 K75 RT - Rocinante; NON-BRICK: 2007 F650 GS Dakar - Betty Blue

Offline Kaos

  • Vlad the Extractor
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  • Posts: 241
Re: Play in rear wheel and leaking of fluid
« Reply #14 on: December 15, 2024, 02:08:19 PM »
800 for a Wilbers. Damn. I mean they're solid however BMw used several brands for their shocks. Hagon or Öhlins were also used by bmw on their k-series which are cheaper options and just as functional. I personally use Yss because their shocks are a good bang for your buck. Now the final drive, the one bought from eBay, does it have better or newer bearings? With the total investment at this point you may as well may have converted to a disc brake setup.
  • Basically Everywhere
  • 1988 K100 RT; 1988 K100 LT; 1989 K 100 LS
"When Kaos reigns, bolts shall break" - Vlad the extractor, 2024

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