31 BMW 1983 R100RS Remove Front Suspension Components

I previously removed the steering components (controls, handlebars, steering damper assembly). Now it’s time to remove the front suspension which includes the front fender, front wheel, front fender brace, front forks and the steering stem.

Remove Front Wheel and Front Fender

NOTE:
I chose to remove the front fender with the wheel in place as I wanted to get the fender to the painter. But it’s easier with less opportunity to scrape the paint on the fender if you remove the wheel first, and I recommend removing the wheel, then the fender. I’ll present this in that order, but the pictures will show the fender missing when I remove the wheel.

The axle is secured with a nut and washer on the left side. There are two axle pinch bolts on each fork tube that keep the axle from spinning. There is a hole in the right side of the axle you can insert a screw driver or the rod supplied with the tool kit to keep the axle from spinning when you remove the axle nut, but with the pinch bolts tight, you shouldn’t need to do that.

Front Axle Nut & Flat Washer

Front Axle Nut & Flat Washer

Front Axle Hardware Detail

Front Axle Hardware Detail

Remove Front Axle Pinch Bolt

Remove Front Axle Pinch Bolt

Front Axle Pinch Bolt Hardware Detail

Front Axle Pinch Bolt Hardware Detail

After I get the axle nut off and the pinch bolts are loosened (in my case, I removed them since I’m disassembling everything), I use a screw drive and insert it into the hole on the right end of the axle to draw it out.

Using Screw Driver To Pull Front Axle Out

Using Screw Driver To Pull Front Axle Out

The “top hat” insert that fits into the dust seal of the left wheel bearing can come out, which mine does, so remember to insert it back into the hole before you install the axle.

Front Wheel Bearing "Top Hat" Came Loose

Front Wheel Bearing “Top Hat” Came Loose

There is a steel sleeve that acts as a spacer that goes on the right end of the axle next to the threads. I put it on the axle with the axle nut so it doesn’t get lost.

Axle with Right Side Spacer

Axle with Right Side Spacer

The fender is secured to the fork brace with four carriage bolts and acorn nuts. I remove them.

Front Fender Secured with Acorn Nuts

Front Fender Secured with Acorn Nuts

Under the acorn nut is a flat washer that sits on top of a rubber grommet that protects the paint on the fender. The rubber can stick to the fender and the washer, as mine did, so I use a small screw driver to gently pry the rubber grommet off fender and not scratch the paint.

Remove Front Fender Rubber Grommet & Flat Washer

Remove Front Fender Rubber Grommet & Flat Washer

Front Fender Mounting Hardware Detail

Front Fender Mounting Hardware Detail

The carriage bolts fit inside the fender brace in the inside set of square holes.

Fender Mount Hardware Fits In Inside Square Hole in Fork Brace

Fender Mount Hardware Fits In Inside Square Hole in Fork Brace

Remove Fork Brace

This bike has the stock BMW fender brace the fender mounts to–with the mud on it in the picture below–and a San Jose BMW aftermarket fork brace that fits around it.

Front Fender Removed Showing Two Fork Braces-Stock (Muddy) and San Jose (Black)

Front Fender Removed Showing Two Fork Braces-Stock (Muddy) and San Jose (Black)

I pull the rubber dust covers up the fork tubes.

Fork Dust Cap Pulled Off Fork Slider

Fork Dust Cap Pulled Off Fork Slider

The fork braces are secured to the fork sliders with four Allen bolts, washers and lock nuts that I remove.

Remove Fork Brace

Remove Fork Brace

Fork Brace Mounting Hardware Detail

Fork Brace Mounting Hardware Detail

I slide the fork braces down the fork sliders to remove them. They are pretty tight so I use a rubber mallet to remove the stock fork brace from inside the San Jose fork brace.

Remove San Jose Fork Brace & Stock Brace By Sliding Them Down The Fork Sliders

Remove San Jose Fork Brace & Stock Brace By Sliding Them Down The Fork Sliders

Separating The Stock Fork Brace From the San Jose Brace

Separating The Stock Fork Brace From the San Jose Brace

San Jose Fork Brace & Stock Brace Removed

San Jose Fork Brace & Stock Brace Removed

Remove Front Forks

I drain the forks, remove the fork sliders and then remove the fork tubes with the damping rods still installed. I’ll pull out the damping rods when I rebuild the front forks.

Drain Forks

There is a fill hole under the top black plastic vanity cover and a drain hole on the bottom of the fork slider. I use a screw driver to pry the vanity cap off.

Fork Top Nut Black Plastic Vanity Cover

Fork Top Nut Black Plastic Vanity Cover

Fork Top Nut Vanity Cover Removed

Fork Top Nut Vanity Cover Removed

Then I remove the Allen bolt that is in the fork oil filler hole.

Remove Fork Top Cap Nut Fluid Fill Bolt

Remove Fork Top Cap Nut Fluid Fill Bolt

Fork Top Nut Fluid Fill Bolt Detail

Fork Top Nut Fluid Fill Bolt Detail

The bottom of the fork has a large Allen bolt that secures the damper rod to the fork slider and a smaller Allen bolt with crush washer that is the fork oil drain. I remove the smaller bolt and drain the oil.

Fork Slider Bottom Detail

Fork Slider Bottom Detail

Remove Fork Slider Allan Drain Bolt

Remove Fork Slider Allen Drain Bolt

Fork Slider Allan Drain Bolt Detail

Fork Slider Allen Drain Bolt Detail

Remove Fork Sliders

I use an electric impact driver to remove the large Allen bolt with copper crush washer from the bottom of the fork slider.

Electric Impact Wrench Makes Slider Bolt Removal Easy

Electric Impact Wrench Makes Slider Bolt Removal Easy

Remove Fork Damper Rod Allan Bolt

Remove Fork Damper Rod Allen Bolt

Fork Damper Rod Bolt Detail

Fork Damper Rod Bolt Detail

Remove Fork Slider From Fork Tube

Remove Fork Slider From Fork Tube

The damper rod is exposed. There is an aluminum bumper in the bottom of the fork slider, so be sure to remove that from the fork slider so it doesn’t get lost.

Fork Damper Rod Detail

Fork Damper Rod Detail

Fork Damper Rod Bottom Bumper Ring Sits At The Bottom of Fork Slider

Fork Damper Rod Bottom Bumper Ring Sits At The Bottom of Fork Slider

Fork Damper Rod Bottom Bumper Ring Orientation

Fork Damper Rod Bottom Bumper Ring Orientation

Fork Damper Rod Bottom Bumper Ring Fits Inside the Bottom of the Fork Slider

Fork Damper Rod Bottom Bumper Ring Fits Inside the Bottom of the Fork Slider

Fork Sliders Removed

Fork Sliders Removed

The bottom of the fork slider has a snap ring that secures the metal plug in the bottom. I don’t remove it.

Fork Slider Bottom Detail

Fork Slider Bottom Detail

Remove Fork Tubes

The fork tubes are secured with a large nut to the top fork plate and with a pinch bolt in the bottom fork triple clamp.

I use a special 36 mm socket to remove the top nut. The face of the socket has been ground flat as the top nut is thin and the taper in a standard 36 mm socket will not engage the nut fully and you will round it off when you try to remove it.

36 mm Socket With Face Ground Down Flat

36 mm Socket With Face Ground Down Flat

36 mm Socket with Face Ground Down Flat

36 mm Socket with Face Ground Down Flat

I like to use my air impact wrench to remove these nuts. They are torqued to 75-80 FT-Lbs and the impact wrench gets them out without damaging them.

NOTE:
if you push the forks to the stop and then use a socket wrench to remove the nuts, you will deform the lower fork triple clamp which causes the forks to be out of alignment. That results in higher “sticktion” and a rougher ride.

Remove Fork Top Cap Nut

Remove Fork Tube Top Cap Nut

Fork Top Nut Hardware Detail

Fork Tube Top Nut Hardware Detail

There is a piece of PVC plastic pipe acting as a spacer to adjust front fork sag installed by a previous owner. Unexpectedly, I find an aftermarket adjustable fork spring inside that has two springs, a longer lower spring and shorter upper spring, with a threaded adjuster between them.

PVC Pipe Spacer for Spring Preload

PVC Pipe Spacer for Spring Preload

Aftermarket Fork Spring Components

Aftermarket Fork Spring Components

Aftermarket Upper Fork Spring Detail-Cap at Right is Stock Component

Aftermarket Upper Fork Spring Detail-Cap at Right is Stock Component

Aftermarket Fork Spring Adjuster Detail

Aftermarket Fork Spring Adjuster Detail

The last thing to remove is the pinch bolt on the fork triple clamp. I remove the Allen pinch bolt and use a large blade screw driver to spread the halves of the fork tube clamp to make it easy to slide the tube down and out of the fork lower triple clamp. I tap the screw driver gently into the slot to spread the clamp. If you pound hard on the screw driver you can damage the clamp which is made out of aluminum. Also, the fork tube may slide out under its own weight when you tap the screw driver so hang on to it so it doesn’t fall out, hit the floor and dent the bottom edge of the fork tube {Don’t ask me how I know this 🙂 }

Lower Triple Clamp Allan Bolt

Lower Triple Clamp Allen Bolt

Remove Lower Triple Clamp Allan Bolt

Remove Lower Triple Clamp Allen Bolt

Lower Triple Clamp Hardware Detail

Lower Triple Clamp Hardware Detail

Spreading Lower Triple Clamp To Remove Fork Tube

Spreading Lower Triple Clamp To Remove Fork Tube

Sliding Fork Tube Down and Out of Fork Lower Triple Clamp

Sliding Fork Tube Down and Out of Fork Lower Triple Clamp

Remove Steering Stem & Fork Top Plate

The steering stem fits inside the steering head on the frame. It is secured by a large acorn nut in the center of the fork top plate. I remove it with a breaker bar, but I could have used the air impact wrench to remove it as I did for the fork top nuts. Once the acorn nut is removed, the fork top plate comes off.

Steering Stem Cap Nut

Steering Stem Cap Nut

Removing Steering Stem Cap Nut

Removing Steering Stem Cap Nut

Steering Stem Cap Nut and Top Plate Removed

Steering Stem Cap Nut and Top Plate Removed

I use the hook spanner in the bike tool kit to remove the slotted steering head bearing preload nut. When the nut comes off, I can remove the chrome vanity cover over the top steering head tapered roller bearing. It’s very grimy.

Took Kit Hook Spanner For Removing Slotted Nut

Took Kit Hook Spanner For Removing Slotted Nut

Remove Slotted Nut

Remove Slotted Nut

I use a plastic mallet and to strike the steering stem so I can remove it from the steering head. Again, to prevent damage to the fork lower triple clamp if it crashes to the floor, I hang on to it while tapping it out of the steering head.

NOTE:
I didn’t remove the top roller bearing first. It’s a press fit on the stem and comes off when I drive the stem downward.

Steering Stem Removed

Steering Stem Removed

I put the top tapered roller bearing on the stem to show it’s location.

Steering Stem Top Bearing

Steering Stem Top Bearing

Here is the front of the bike now that all the front end parts have been removed.

Front End Removed

Front End Removed

Front End Removed

Front End Removed

Revisions

2019-11-27  Edits and typos.
2022-01-02  Correct typos.

4 thoughts on “31 BMW 1983 R100RS Remove Front Suspension Components

  1. Brook, first, thanks for your excellent documentation. Your site has helped me more than every other airhead resource combined.

    Now the question: Did you remove the steering-head outer races before taking the frame to be powder-coated?

    eric Z

    • Hi Eric,

      First, thank you for your kind words.

      I think it’s best to remove them before powder coating the frame if you plan to replace them. The frame gets heated to around 400 F to melt the powder coat so if you leave them in, the races should still be okay for continued use.

      Best.
      Brook.

  2. Hi Brook,

    First of all I would like to thank you for such a good tutorial, it has helped me a lot to rebuild and transform my BMW R100.

    Now that it is finished, I am having some leakages on the bottom of the fork sliders. I replaced the bolts (small & large) and the metallic seals, I also put some sealing Loctite, but nothing is working. I was wondering if it has to do with the metal plug that is in the bottom, is there any o-ring (or other seal) that prevents the leakage. I fear that when I disassembled everything for painting, I did not remove this plug, so now I was thinking that inside there is a seal that I did not replaced and now is provoking this leakages.

    Please, I would appreciate if you could send me a couple of tips so I could decide to remove that metal plug or not.

    Thank you very much in advance.

    BR,

    Ander

    • Ander,

      I would clean up the forks and then try to verify exactly where the leak is coming from: seals, bottom plug, drain plug, etc. Forks are different on different models and years so I don’t know exactly which model/year you have.

      Best.
      Brook.

Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.