I documented removing the handlebars, headlight shell fenders and front wheel here:
Removing the fork tubes is covered here:
This page covers removing the steering stem, bearings and races and replacing them.
Here are the part’s I needed. The Triple Tree Seal Ring is often damaged when removing the lower bearing race, and in my case, it was missing. I replaced the Chrome Cap as the chrome on original was in sad shape with chrome plating flaking off.
|07 11 9 985 070||Steering head bearing, top & bottom|
|31 42 1 234 509||Triple Tree Seal Ring (aka, Lower Dust Cap)|
|31 42 2 000 312||Chrome Dust Cap|
I use the hook spanner tool in the bike’s tool kit.
I use a steering head bearing puller from BMW that I borrowed from a BMW mechanic.
You can also get one from Cycle Works (Cycle Works Steering Stem Bearing Puller).
Remove Steering Stem
This is where I started from. At this point, the steering stem is still connected to the steering head with the slotted nut as shown below.
Remove the slotted nut with the hook spanner tool in the bike’s tool kit.
The chrome dust cap lifts off to expose the top steering head bearing.
Using a rubber mallet, knock the steering stem out of the steering head. The upper bearing is a shrink fit onto the stem and will slide up the stem, but it takes a couple of firm blows to get it to slide. Keep your hand under the steering stem to catch it so it doesn’t slam into the floor.
Here’s the steering stem after removing it from the steering head. I put the top bearing back on the stem and you can see the shiny band on the stem underneath which is where it seats on the stem. Also you can see the bottom bearing and race attached to the steering stem.
Inspect Steering Stem Bearings
This shows the Brinelling marks in the upper race. This is caused by the tapered roller bearing pounding into the race and the fact the roller bearing never rotate very much. Over time, the race gets dented. You feel this as notchy steering when moving the handlebars either side of center.
BMW Steering Head Bearing Puller Assembly
I borrowed the BMW bearing puller from Clem at BMW of Denver who loaned it from his personal stash of tools. It is a “Beast”, that’s for sure.
The puller has two threaded rods; an inner one attached to the jaws and an outer threaded rod that holds the puller arms and has a hex nut for a crescent wrench at the top.
The ring goes on top of the steering head.
The jaws of the puller use the inner threaded rod to push the wedge in between the jaws so the lip of the jaws is driven underneath the race.
Remove Steering Stem Bearing Races
Turn the jaw assembly on the inner rod raising it and spreading the jaws until they are firmly under the race. Then tighten the lower nut to secure the jaws. This is cumbersome as the puller has a lot of moving parts and the outer arms get in the way. I folded them over the top of the puller to keep them out of the way.
This shows the jaws spread underneath the race. After tightening the lower nut to secure the jaws, turn the outer threaded rod to bring the outer arms down until they rest on top of the ring being careful they don’t cover the edge of the race. Tighten the outer rod enough to snug the outer arms down on the ring. Again, this is cumbersome with so many moving parts.
The outer threaded rod has a hex nut for a crescent wrench. Use a crescent wrench to turn the nut to pull the rod and the race out of the steering head. It will take a good deal of force to get the race to start moving.
Here is a better view of Brinelling on the inside of the top race.
To remove the lower bearing, I used a Dremel tool with a cutoff wheel and cut through the cage to remove the bearing cage and the bearings. The bearing is a shrink fit onto a wide area at the bottom of the steering stem. I used the Dremel cutoff wheel to cut notches in the bearing shell and then used a cold chisel and a hammer to crack the shell. I drove the chisel downward near the outer edge of the shell to crack it. I was careful to avoid scoring the steering stem.
Another technique is to use a propane torch and heat the shell to a dull red and then use a hammer and chisel on the outside edge of the shell to drive the shell up the stem.
Here is the lower race after I removed it.
Installing the New Bearings and Races
The bottom bearing has to slide over the upper bearing land and the lower land until it seats at the bottom of the stem. The technique I use is to freeze the steering stem and heat the bearing. But before I did that, I cleaned and polished the aluminum lower triple clamp making sure there are no nicks or gouges in the lands where the bearings seat.
Here’s the parts for the bottom bearing including the new lower dust cap.
I decided to have an insurance policy to ensure I got the lower bearing to seat. I took the old race to cover the bearing and the Cycle Works swing arm puller metal tube. I could slide the tube over the stem so it was on top of the old race. I figured I could hammer on the top of the tube to drive the bearing all the way to the bottom of the stem if it hung up and I wouldn’t damage the bearing.
I took the steering stem out of the freezer and slide the bottom dust cap on.
I heated the bearing with a heat gun until it was about 220 degrees F as verified with my handheld infrared thermometer. Using welding gloves, I picked up the bearing and put it on the stem and it dropped all the way to the bottom. No insurance required 🙂
I put the top and bottom races in the freezer for an hour to shrink them a little before driving them into the steering head.
I put the flat side of the the Cycle Works swing arm puller aluminum block on top of the race and hammered it into the top of the steering head until it was seated and flush with the top of the head. You can hear a change in tone when it is seated.
Since I stripped the bike to the frame, I could turn the frame over to drive in the lower race. I put the top of the steering stem on a board, centered the frozen race in the hole and with the flat side of the aluminum block on top, drove it in until it was flush with the bottom of the steering head. The lower race is recessed into the steering head. I had read that the old race can be put upside down on the new race and then hammered in to seat the lower race. I was concerned that I wouldn’t be able to get the old race out, but it was easy to wiggle loose. And, I could have used a screw driver under the inner lip to rock it out.
Install Steering Stem in Steering Head
The upper bearing is seated on the land at the top of the stem by tightening the ringed nut until it seats. Here is the order of the top bearing parts, top to bottom, lower to upper.
The bearings need to be packed with grease, and I use NLGP2 EP red grease.
Here are the packed top and bottom bearings.
Insert the steering stem into the bottom of the steering head.
Which Side Goes Up?
The slotted nut has a wide face and a narrow face. So, which face goes up? The wide face does. Here is the incorrect direction;
And, here is the correct orientation.
Put the top bearing on the stem and hand tighten the slotted nut on the stem. The bearing will sit high on the stem until it is seated.
Tighten the slotted nut using the ring spanner from the tool kit until it is tight. This will drive the top bearing down on the stem until it is seated.
Then remove the slotted nut, put the top chrome dust cover on and tighten the slotted nut again until snug. After I install the forks, I’ll adjust the bearing pre-load.
This is a milestone on the project as this is the first time I installed parts back on the frame. 🙂
2017-04-04 Update organization and Table of Contents. Add Cycle Works tools.