'83 R65 Wheel Bearing Adjustment

[Mike V]

Flybot,

Sorry I'm getting to this thread so late.  I most closely agree with Armen's post with some amendments.  There's not a short answer to the process, I would recommend re-visiting Bum's web page, and reading Section 4 of his web site on Bearings and Preload over a few times.  We've been in the process of editing/improving the instructions the past few days.  He's included some graphics to help some.  In Bum's defense; it's a difficult task to give a tutorial as involved and complcated to such a wide range of readers with a wide variety of experience, knowledge and skill levels in a smooth delivery without detours.  Correct preload determination can be a safety issue and not taken lightly.  My personal opinion.

Contact me by PM, I can try to talk you through it the best I can with a phone call maybe later this evening.  There's some special tools and equipment involved.  And it's important for me to know some details on where you are and where you've been in regards to the work you've already performed.

Going for a ride...

mvtv@cox.net

-Mike V. / San Diego

[flybot]

Thanks for the offer! I wont be getting into it until the next weekend probably. New seals on order. If I run into any issues I know where to call.
Thanks

[Ed Miller]

How many wheel bearing failures have you experienced in owning a car

Two or three, I'm not sure which.  At least one on my '58 Chevy, before the Napco conversion.  And my wife's '85 Civic wagon had a front wheel bearing go out.  Those suckers are expensive, and are the same kind as your CRX has.  The nice thing about cars is you usually get lots of growling warning and they don't make you wreck.  

I'm pretty convinced that our BMW wheel bearings would also give some advance warning before they failed in such a way as to lock up a wheel.
But I can't prove that.

[flybot]

OK, here is the follow up.

As stated, I initially thought the rear bearings were loose. I didnt suspect the front. I ordered the spacer kit and a few seals, and I did the bearing adjustment last night. Not what I expected.

The front wheel needed .10 mm tighter. The rear needed .15 mm looser. The rear was pretty tight and Im glad I have only done about 150 miles since they were installed. It was suprising. Also, while going through everything I found that one of the shocks was not set the same as its opposite. One full soft, one full firm. That must have been left over from the restoration rebuild.

The lesson learned: New bearings=new bearing adjustment.

Here is how I adjusted mine. It may not be the perfectionist way, but I know what a tight or loose bearing feels like.


The bearing adjustment kit is a rather ingenious kit. Instead of having a "wedding ring" of every size, the kit includes a small and medium size ring and ten 0.05 mm shim rings. Enough to make every needed size.

The adjustment takes several trial and error tests to get the setting right.

I did my front wheel first.

-Take off the front brake caliper(s) and secure them out of the way with zip ties.
-Remove the wheel and remove the left seal. The wedding ring should be under the bearing under the left seal. I had spare seals available, but I used a automotive seal remover and my seals both came out with out any damage what so ever. Since they had less that 200 miles on them I chose to reuse them.
-Re-install wheel and torque to spec. For my '83 I used 32 ft.lbs
-Spin wheel and see how it feels. Rock back and forth and see if any looseness is present. I could feel a slight knock on mine.
-Remove wheel again. I needed to tighten my bearing, so that means a thinner wedding ring.
-Remove wedding ring and measure thickness with a micrometer. Mine was at 6.65 mm. As a starting guess, I decided to try 6.45 mm using the bearing adjustment kit.
-Re-install wheel and give it a spin. If its too tight, try a setting between current and where you started. Too loose still, take off another .10 mm (two shims).
-Re-install and repeat until you have the tightness right.
-NOTE: when it gets too tight it will be apparent. From that point go one size thicker. and check again. As you change sizes to the tighter side, check for over tightening of the bearing as you torque the nut down.
-Since I still had one more wheel to go and only one adjustment kit, I took the correct spacer size, measured it, and then took the old wedding ring and used a file to carefully reduce its thickness to the required thickness.
-Re-install with re-sized spacer and recheck tightness.
-When your sure its right, re-install seals and reassemble front end.

For the rear wheel:

You cant check the bearing of the rear wheel when its on the bike. Too much drag with the rear drive. You need to make a spacer for the drive side. Pretty easy and it cost me about $6.

I bought 3/4" galvanized electric conduit and a 3/4" washer. Cut the conduit to 3.25". When testing off the bike, assemble the axle, and on the drive side of the wheel, put on the hat, 3/4" washer, conduit spacer, and washer and axle nut. Tighten to spec. I cut the conduit with a tube cutter, like for copper pipe. That way you get a nice flat cut. Seemed to work pretty well. Just make sure your spacer is pushing against the "hat" and not reaching over the hat to the seal/bearing area.

The spacer tube needs to be a min of 17 mm to go over the axle, and a max of 22 mm to stay on the hat (or use a washer like I did).

-Remove the seals as before.
-I used the same "feel" test as the front wheel, initially using the existing wedding ring as a starting point.
-From there, the trial and error adjustment is the same as the front.

[Barry]

Good write up.  

There is a lot of mystery around wheel bearing adjustment but it's not rocket science and actually doing it is far easier than reading about it. When I first got my bike I checked the bearing adjustment using the feel method based on Duane Aushermans write up http://w6rec.com/duane/bmw/wheel_bearing/index.htm and concluded they were fine. I stopped short of the full 32 ftlbs as 25 ftlbs is considered adequate if all traces of play have gone by that point which was the case. I think in any case that the 2 thou increments of adjustment are too big without using some variation in torque setting to compensate. When I checked again recently to re-grease and do a wheel balance I found no detectable difference in the set up.

There is some discussion doing the rounds on other forums about measuring frictional torque using string and a spring balance or a low range torque wrench. This is considered the correct and perfectionist way to it but is probably not absolutely necessary. If I have no perceptible play and the bearing doesn't get excessively hot in use then I'm happy with that.  

Good to see someone else thinks seals can be re-used when appropriate.

[flybot]

Thanks for the comments. Yes, the .2 mm initial stab to tighten was too much. I made an edit in the post about checking the tightness when going to a tighter spacer. It was just a guess. I really had no idea what was appropriate since Id never adjusted a bearing in this way.

The feel method does rely on a bit of experience to determine what is right. The scale and string procedure seems good, and you probably cant go wrong. But I dont have an appropriate scale, and Im confident I adjusted mine to a safe setting.

Oh, and the bike does feel much better now. It still seems like it has a lot of flex compared to other bikes Ive riden. But that seems to just be a characteristic of these great bikes.

[montmil]

I've used the Ausherman Technique from the get go and find it to be more than sufficient. I like the simplicity of both the idea and the technique.

The tapered roller bearing preload on the rear axle of my 1986 VW Cabriolet is set following the popular Bentley manual's instructions:

... fit the thick washer and tighten castellated nut until the washer can be barely moved by using a flat blade screwdriver to push on the washer. Insert cotter pin.

Not too far removed from Duane's process for the BMWs.

[Bob_Roller]

Here's the process of determining proper bearing preload on  737 aircraft main wheels .

While rotating wheel, tighten axle nut to 300 ft/lbs, loosen axle nut to zero, torque to 100 ft/lbs, then tighten axle nut until next holes for safety bolts can be installed .

Not exactly a very precise method to say the least !!!!!!

[Mike V]

Flybot,

They say necessity is the mother of invention. No, not the precise method of preload - I would agree.  But it sounds to me that you have acquired some important knowledge of the general operation of the bearing stack.  That in itself is a most important result of your efforts.

Just want to go on record saying I wouldn't recommend your procedure.  Not saying you didn't find the happy and safe zone of preload.  And congratulations on saving a couple of dollars on the grease seals.

-Mike V.