I’m going to rebuild the forks and I’m going to install the Race Tech Gold Gold Valve Cartridge Emulators.

This is the first time I have used them. I’ve heard that they make a significant improvement in handling and compliance compared to a damper rod design.

The stock springs can’t be used with the cartridge emulators so I install the correct Race Tech springs based on my specifications.

You can read all the details of how I do this work here.

• 31 BMW R100RS/RT Rebuild Forks With Race Tech Cartridge Emulators

And this is a video summarizing the work.

VIDEO: 1983 BMW R100RS Rebuild Forks with Race Tech Cartridge Emulators

I refreshed the wearable components using a fork rebuild kit I got from Tom Cutter at Rubber Chicken Racing Garage.

The damper rods have to be modified so there are six compression damping holes in the bottom of the rod. Race Tech supplies a piece of 3/4 inch PVC to make fork spring preload spacers to achieve the correct preload based on my specifications.

I repainted the fork lower sliders as they had a lot of stone chips.

 

I’m going to powder coat the wheels, so I remove the disk brake rotors. I refurbish the three rotors to remove grunge and get the patina on the disk carriers back to factory condition. I also clean out the holes and sand the disks so the new disk pads will bed in and not get fouled from brake pad grunge baked onto the rotors or the dirt and grunge lodged inside the disk brake rotor holes.

Here are all the details about how I do this work and a short video summarizing the work.

• 34 BMW 1983 R100RS Remove, Refinish, Install Disk Brake Rotors

VIDEO: 1983 R100RS Remove-Refurbish-Install Disk Brake Rotors

Here are a couple pictures of before and after.

 

When I had the heads rebuilt by Randy Long I had him modify them for dual plugs. I have made that modification on two other bikes and I like the improvement in gas mileage and the smooth running even on lower octane gas. So I have to replace the stock coils with coils that have two secondary ports so each coil connects to two spark plug wires.

This bike came with a BMW electronic ignition that includes a “bean can” with Hall effect sensors that act like mechanical points.

The Hall effect sensors use a rotating magnetic field to open an electronic switch in the Hall effect sensor to stop current flow in the coil primary triggering a large voltage in the coil secondary. This is exactly what mechanical points do to trigger a high voltage spark in the spark plugs.

There have been some issues with the BMW electronic ignition. One in particular is that Hall effect sensors do not like heat and fail over time. When they do, you are stranded unless you have a second bean can with you. You can’t remove and disassemble the bean can by the side of the road.

I decided to remove the stock BMW ignition system and install a system that uses an optical switch for the points and a electronic ignition control module from Euro MotoElectrics. The ignition control module has three different ignition advance curves you can select from including one that works well with dual plug engines.

Since I have dual plug heads, I also install dual port coils.

You can read about how I do this work here:

• 12 BMW R100RS Install EME Optical-Electronic Ignition System

And, this is a video summary of the procedure.

VIDEO: 1983 BMW R100RS Install Euro MotoElectrics Optical-Electronic Ignition System

Here is what the final installation looks like.

 

The steering head bearings are roller bearings. But, roller bearings rely on the roller rotating to keep distributing grease between the roller and the outer race to prevent metal-on-metal contact. However, the front forks spend most of their time in one position and are subject to shock loads as the front end goes over bumps. This means grease gets extruded from between the rollers in the inner race and the outer race allowing metal-to-metal contact, and the shock loads pound the roller against the outer race creating grooves in the race. This creates notchy steering, and when it’s really bad, you can feel resistance when trying to turn the forks from the center position.

When I removed the steering head bearings, they showed the distinctive vertical stripes indicating the outer race has Brinelling, which is the groove pounded into the outer race.

I use the Cycle Works tools for removing and installing the steering head bearings. See the “Replace Steering Head Bearings” section below for a link that shows the Cycle Works tools are assembled and used.

I removed the old outer races and the inner race on the bottom of the steering stem. Then I refinished the lower fork brace and then installed the new lower inner bearing race and then installed the steering stem in the steering head.

Here is a link to the description of how I do this work

• 31 BMW 1983 R100RS Replace Steering Head Bearings

And here is a video summarizing how I remove and install the steering head bearings.

VIDEO: 1983 BMW R100RS Replace Steering Head Bearings