36 BMW 1973 R75/5 Refinish Wheels, Install New Spokes, Repair Spun Wheel Bearing

I decided to replace the original spokes that are chrome plated with new stainless steel spokes. I’ve read about how to lace and true wheels and felt there is more technique involved than I was up for, so I decided to use a well respected local wheel builder, Woody’s Wheel Works, here in Denver, CO.

I purchased front and rear wheel stainless steel spokes from Hucky’s  who provides these from time to time. Unfortunately, the rear rim spoke holes had been enlarged so the stock spokes Hucky supplied were too small. And more unfortunately, it was more than 90 days after I purchased them when I found out, so no return was possible 🙁  Oh well, they will get used or sold on eBay at some point.

Parts List

These are the parts needed.  I bought the stainless steel spokes and provided them to Woody’s. However, the front rim spoke holes had been enlarged and Woody’s had to use larger spokes and nipples.  I show both the original part number and Woody’s part number for the larger spokes and nipples.

Part # Description Qty
36 31 1 230 334 Front wheel, outer shaft seal 1
36 31 1 231 701 Front wheel, inner shaft seal 1
36 31 1 230 430 Front wheel, gasket 1
07 11 9 985 005 Wheel bearings, rear, single 1
36 31 1 230 334 Rear wheel, outer shaft seal 1
36 31 1 231 701 Rear wheel, inner shaft seal 1
36 31 1 230 430 Rear wheel, gasket 1
SKF Part # 99157 Speedi-Sleeve 1
36 31 1 234 591 SSp Spoke Set, 18″, nipples, 140mm, Stainless
{STOCK BUT HOLES WERE OVERSIZE}
1
9S 9ga stainless steel 18″ spoke
{OVER SIZE FROM WOODY’S}
40
N9289S 9ga stainless steel nipple
{OVERSIZE FROM WOODY’S}
40
36 31 1 234 592 SSp Spoke Set (40), 19″, nipples, 153mm, Stainless 1

Wheel Inspection

I inspected the rims and hubs for general wear and tear. The steel brake surfaces are in good condition, the rear drive coupling splines are not worn and rear drive coupling rivets are sound.

Rear Wheel, Bearing Cover Side

Rear Wheel, Hub Cap Side

Brake Shoe Side, Rear Hub

Rear Wheel, Brake Side

Bearing Cover Side, Front Wheel

Front Wheel, Hub Cap Side

Brake Shoe Side, Front Wheel

Front Wheel, Brake Side

But, the rear rim had large, deep gouges in it.

Rear Rim Gouges

Rear Rim Has Deep Gouges

The front only had some scratches and dings and they looked like they would sand out okay.

Gouge on Front Rim

Front Rim Has Dings and Scratches

I decided to use a rear rim left over from my R75/6 project. I have both front and rear wheels from updating the bike to snow flake cast rims.

Removing the Tires and Tubes

The first step is dismounting the old tires and tubes. I used plastic rim protectors to avoid inflicting any more damage to the rims.  In about 40 minutes, I had a stack of old rubber in the corner and only one dusted knuckle :-).

Old Tires and Tubes

Old Tires and Tubes Removed

Then I removed the chrome hub caps to expose the wheel bearing assemblies and the ends of the spokes. The bolts are rusted so I’ll replace them with new clean ones.

Removing Chrome Hub Cap

Removing Chrome Hub Cap

Removing the Spokes, Brute Force Method

As the chrome spokes are showing signs of rust, I removed them the quick way using bolt cutters. It’s pretty quick work to cut 40 spokes near the edge of the hub, and it’s a very good idea to have eye protection “just in case” something goes flying.

Bolt Cutter

Bolt Cutter for Brute Force Approach

Cutting Spoke Near Hub

Cutting Spoke Near Hub

Then I can lift out the hub and empty all the spoke ends out of it and after removing the rim tape, I removed the cut spokes from the rim.

Front Rim with Cut Spokes

Front Rim with Cut Spokes and Hub Removed

Front Hub Removed

Front Hub with Spoke Ends

Rim Removed with Cut Spokes

Spokes and Rim Tape Removed

The five bolts that hold the hub cap on also secure the bearing cover. The cover has a gasket that goes between it and the hub. Removing the bearing cover exposes the tapered roller bearing races on the left side.

Front Hub with Bearing Cover and Gasket

Front Hub with Bearing Cover and Old “Crusty” Gasket

The inner race with the tapered rollers can be lifted out. The rest of the wheel bearing assembly including the inner and outer bearing race on the right side are removed in a single stack by heating the hub to 220 degrees or so and using the axle what a spacer to hold all the parts in the stack together. Bob Fleischer has a good write up on doing this work as does Duane Auscherman.

Spun Bearing on Left Side of Rear Wheel

When I removed the rear hub and took the bearing cover off, all the internal parts fell out. 🙁  This is NOT supposed to happen. It means the outer race of the left side bearing has gotten loose in the aluminum hub and spun so it no longer is captive in the hub.

Here are the parts from the left side of the hub. The bearing cover and gasket are on the left, followed by the left inner bearing with tapered rollers, the outer bearing shell, the “wedding band”, then the inner spacer and the outer spacer which are the two large cylinders on the right.  The inner bearing race with tapered roller bearings and the wedding band can be taken out by hand, but the outer bearing shell, the inner spacer and outer spacer should have stayed captive in the hub.  It’s the outer bearing shell that holds the spacers in the hub and when it has spun in the aluminum hub, then everything falls out.

Bearing Stack, Outside (Left) to Inside (Right)

Bearing Stack, Outside (Left) to Inside (Right): Bearing Cover & Gasket, Inner Bearing Race, Outer Bearing Race, Wedding Band, Inner Spacer, Outer Spacer

The larger diameter, or outside spacer, presses on the outer race of the left and right side bearings while the smaller diameter inner spacer with ridges presses on the inner races that have the tapered roller bearings. The metal ring that looks like a wedding band fits into one side of the inner spacer and adjusts the gap between the inner spacer and outer spacer. That gap adjusts the amount of pressure put on the inner races as they press into the outer races when the axle nut is tightened.

Inner spacer with Recess for Wedding Band

Inner spacer with Recess for Wedding Band Used to Set Bearing Pre-load

This adjustment is called setting the bearing pre-load. It has to be adjusted carefully when reassembling the bearings. Duane has a method to set the pre-load and Bob has a different method. Both should work.

In my case, the rear hub needs to be repaired so the outer race is firmly captured in the hub. Repair options I found in an web search include:

1. Using locktite on the outside of the outer race to secure it to the aluminum hub.
2. Staking the outer race to try and keep it captive in the aluminum hub.
3. Adding a shim around the outside of the outer race so it is captive in the aluminum hub
4. Buy a new hub.

I posted my problem to the airhead forum on the Micapeak site looking for input on these options and any other ideas. The consensus is:

  • Option 1 can work, but also can fail
  • Option 2 always fails,
  • Option 3 works well,
  • Option 4 is expensive and since new hubs are no longer available from BMW, is not a viable option.

I also got a response from two folks in Australia with a variation on shimming the outer race. Their fix uses a thin steel sleeve called Speedi-Sleeve, provided by SKF bearing company. It is designed for use on shafts that have been scored by the shaft seal. Adding a Speedi-Sleeve stops the oil leaking past the seal and retains use of the original oil seal. The sleeve that fits the R75/5 wheel bearing is #99157. It’s 0.28 mm or 0.011 inch thick so it adds 0.56 mm or 0.022 inch of material to the aluminum hole holding the bearing. It is installed on the outer race with a special tool. Then the bearing stack is assembled on the axle with a spacer (actually, the axle is inserted on the opposite side of the hub from normal usage, but this is  explained in detail in both Bob’s and Duane’s write up) and is put into the heated aluminum hub. This is the standard procedure for installing the bearing stack into the aluminum hub. When the hub cools, it contracts around the Speedi-Sleeve and outer race shell and should hold the shell captive to the hub. This is the solution I’m going to try.

I contacted Woody’s Wheel works and told them I’d like them to try the repair with the Speedi-Sleeve. Also, to simplify greasing the bearings without having to heat the hubs to remove the bearing stack, I asked them to grind the ridges on the inner spacer so it can pass through the outer race. This doesn’t affect the function of the inner spacer and is a suggested modification by both Bob and Duane.

Inner Spacer with Recess

Inner Spacer with Ridges

In the future, I can remove the left side bearing cover, pull out the inner bearing with the tapered rollers and the outer and inner spacers.  Then, with a special bearing lubrication tool available from Cycle Works, I can lube the right side bearing without having to heat the hub and remove the bearing stack. This is simple and avoids possible damage to the hub and the repair to the spun bearing.

Cycle Works “Easy” Wheel Bearing Grease Tool

Removing the Spokes, Gentle Method

Since I’m going to use the rear rim from my R75/6 project instead of the gouged rim on the R75/5, I decided to try the gentle method of removing the spokes, unscrew them from inside the rim. I remove the rim tape and use a large blade screw driver that tightly fits the slot in the nipple and then backed them off about a 1/2 turn going around the rim to relieve the tension uniformly.

Loosening Nipples

Loosening Nipples about 1/2 Turn All The Way Around The Rim To Relieve the Tension

Then I use my power screwdriver to quickly undo the loosened nipples from the spokes.

Removing Nipple with Power Screw Driver

Removing Nipples with Power Screw Driver

In about 10 minutes I had separated the spokes from the rim and I have the chrome spokes and nipples to reuse on another project. The chrome on the spokes and nipples is in good condition, so after I clean them up they should look nice.

R75/6 Chrome Spokes

R75/6 Chrome Spokes Saved for Another Project

Cleaning Up Hubcaps, Hubs and Rims

The hubcaps had a few dents and I knocked them out from the inside of the hub and then cleaned them up with aluminum cleaner and aluminum polish. Nice and shiny.

Polished Hubcaps

Cleaned and Polished Hub Caps

Next, I cleaned and polished the hubs and the rims. I start out using the parts washer with a nylon brush and tooth brushes to get the easy to remove crud off them.  Then, I use brake cleaner on the inside of the brake drum to remove the remaining caked on brake dust inside.  I used “00” steel wool on the steel bake surface to remove rust and built up crud.

I use a wire brush to clean the rough casting surface of the hub.  In the middle of the hub are fins for cooling the hub so you need wire brush with long wires to reach all the way down to the bottom of the groove. I follow that up using “00” steel wool folded into a sandwich and then pushed back and forth inside the grooves.  I use aluminum polish on the wide outer rim of the hub where the spoke holes are to bring out the luster.

Finally, I use 320 grit sandpaper with water followed by 600 and then 1500 grit to polish up the aluminum edge the hub cap mounts into on the left side of the hub. I get a good shine with “0000” steel wool followed by aluminum polish. Here they are packed in a box with the new stainless steel spokes ready to take to Woody’s Wheel Works.

Wire Brushed and Cleaned Hubs

Wire Brushed, Cleaned and Polished Hubs

Cleaned Hubs & New SS Spokes for Woody's Wheel Works

Cleaned Hubs & New SS Spokes Ready for Woody’s Wheel Works

The rims are next. The inside is covered with old tire rubber and glue from the rim tape. I use a wire brush to get them clean. It’s much easier to mount tires if the inside of the rim doesn’t have old rubber on it.

Tire Rubber (left) and Cleaned (Right)

Old Tire Rubber (left) and Cleaned Rim (Right)

Tire Rubber Removed

Clean Inside of Rim with Tire Rubber and Rim Tape Adhesive Removed

I use 320 grit wet sandpaper to sand out the dings, bumps and gouges in the rim. As with the hubs, I followed this with 600 and then 1500 grit wet sandpaper to get a dull shine on the rims.

Ready for Steel Wool "0000"

Ready for “0000” Steel Wool to Bring The Shine Back

Next is “0000” steel wool to bring the shine back to the rims. Finally, I polish them with aluminum polish.  It took me about 6 hours of work to restore the finish to the hubs and rims. They look pretty nice.

Polished Rear Rim

Polished Rear Rim

Polished Front Rim

Polished Front Rim

Woody’s Final Product

Next stop, Woody’s Wheel works to replace the wheel bearing, repair the rear hub from the spun bearing, reduce the diameter of the ribs on the inner spacers, set the bearing preload and to lace and true the wheels with new stainless steel spokes and nipples.

After I brought everything to Woody’s, they found out that the spoke holes in the front hub had been enlarged so the stainless steel nipples I bought (8 mm) are too small. They have larger nipples (9 mm) but they won’t work with the threads on the stainless spokes I provided, so I had them install the larger 9 mm spokes and nipples on the front wheel.

A local bearing supply company they do business with is a source for SKF bearings and Speedi-Sleeves.

The inner sleeve now passes through the outer bearing race.

Inner Spacer Passes Through Bearing Outer Shell

Inner Sleeve Passes Through Bearing Outer Shell

Here you can see the Speedi-Sleeve surrounding the outside circumference of the outer bearing race. It’s a bit more evident at the 6:00 position.

Speedi-Sleeve Installed Around Outside of Rear Bearing Shell

Speedi-Sleeve Installed Around Outside of Rear Bearing Shell

This is the new rim tape with the rotation arrow on the rim.

New Rim  Tape with and Rotation Arrow Inside of Rim

New Rim Tape with and Rotation Arrow Inside of Rim

And, the final laced and trued wheels.

Woody's Wheel Works Final Product

Woody’s Wheel Works Finished Front Wheel

Woody's Wheel Works Final Product

Woody’s Wheel Works Finished Rear Wheel

Mounting Tires and Hubcaps

I bought new tires and rubber tubes, Metzeler Lasertec.  I read that putting the tires in the sun so they can heat up makes them more pliable and easier to mount. So I conducted an experiment.  The outdoor temperature was about 56 F and I placed the tires against a south facing wall for about 15 minutes.  They heated up to 106 F.

Air Temperature about 56 F

Air Temperature about 56 F

Sun Heats Tire to 106 F in About 15 Minutes

Sun Heats Tire to 106 F in About 15 Minutes

The front was a lot harder to mount than the rear. Since it is narrower (3.25 inch) I think it is stiffer and harder to flex. After I got the tubes and tires on the rims, I mounted the hubcaps using the five bolts that hold the bearing covers. Here are the wheels after cleaning and polishing the hubs, rims and hubcaps, new stainless steel spokes and new tubes and tires.

Polished Wheels with New Spokes and Rubber

Polished Wheels with New Spokes and Rubber

14 thoughts on “36 BMW 1973 R75/5 Refinish Wheels, Install New Spokes, Repair Spun Wheel Bearing

  1. Pingback: 1973 BMW R75/5 Rebuild: Wheel Polishing, Bearings and Spokes | Motorcycles & Other Musings

  2. Excellent job. Wish I had time to tackle a project like this. Your last two photos seem to be out of place. Thanks for documenting.

    • Hi Ray,

      Thanks for taking a look. Can you elaborate a bit more about your comment “Your last two photos seem to be out of place”? They are the pictures of the laced and trued wheels, which is what I received back from Woody’s.

      Best.
      Brook.

  3. Nice job, and excellent documentation all around.

    Should the new bearings be installed before building the wheels ?

    Did Woody’s do the bearing work as well?
    I’m thinking of using them for my R75/5 project.

    • Hi Monte,

      Yes I had Woody’s install the wheel bearings for me. I liked their work and they were easy to work with. This is the second time I’ve had them work on BMW wheels and both times they did great work.

      Thanks for stopping by to view the content.

      Best.
      Brook.

      • Thanks

        I live in Denver as well, so I’m thrilled to find your blog, and info on local shops and sources. Just getting back into my R75/5 toaster rebuild after a long hiatus.

    • Ben,

      I haven’t balanced the wheels yet. I have a compact tire balancer that I got from Marc Parnes:
      http://www.marcparnes.com/

      It mounts on two jack stands and works well. I got some adaptors with the balancer so it will work on the /5, /6 as well as the R1150-RS and F650-GS bikes I have.

      I hope that helps.

      Best.
      Brook.

    • Hi Bob,

      Thanks for the kind words and dropping by. I should be posting more on my sojourns in painting soon, so stay tuned.

      Best.
      Brook

  4. Very nice job , will try to do my 75/7 rebuild as well , same wheels but have RT front twin discs ..

  5. Thanks as always for the great write-up. I have read Duane’s and ‘Bum’s articles repeatedly but your photos and notes were what finally made it all click in my mind. You have a real talent for distilling these procedures to their essence in a clear and concise way.

    What I finally determined is that the PO of my R60/6 must have made the modification to allow greasing the right-side bearings without heating and removal of the stack – when I removed the cover and top hat spacer, the inner spacer came right out but the outer race is still firmly in place. This had me puzzled until I re-read your posts here.

    Final drive is back in place, doing the rear wheel now so I can bolt it all up and torque the driveshaft bolts. Thanks again!

    -Joshua

    • Hi Joshua,

      Thank you for stopping by and making use of this write-up. That simple modification was suggested by Bob Fleischer (aka, Snowbum) IIRC. I plan to make it to the bearing stacks on my other bikes as I get to them.

      Glad to hear you are making good progress on your project.

      Best.
      Brook.

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