The New And Improved Unofficial R65 Forum V2
Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: BPT on April 04, 2019, 08:26:56 AM
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After what I was expecting to be a simple tire replacement, I've found that I might have a problem with my front wheel bearings. I noticed some runout after having my local shop install it and found that they hadn't seated the bead correctly. After a couple of visits and losing faith in them for what should have been a straightforward thing, I went elsewhere for a second opinion. This works on Euro bikes but not BMW's (Triumph, Ducati, etc.)
The mechanic there checked the tire, deemed it good but noticed some slop in the bearings. He made it sound like replacing those would be simple which is what I thought also. I should have known better..........
I spent a couple of hours last night checking into that.......jeeeeez, what a confusing bunch of crap that was. I started with Clymer's - sounded like preparing to deliver a baby with all of the talk of hot water and towels, then getting to the end where they tell you a special BMW tool is necessary for doing the preload. Ok, thanks for that.
Went to Snowbum - uuhhhhh.......... Bless his heart, I certainly respect his knowledge and experience and truly appreciate the time and effort he's put into making it available online, but ............ I couldn't make heads or tails out of what to do from that article. I'm pretty sure I lost some brain cells there that will never grow back.
I then read Duane Asherman's write-up and it was more relaxed and made more sense than the others, kind of.
So, specifically for the R65, would someone here be willing to offer up some advice here? I've gathered that an 83 R65 should have the wheels that make some of this easier - it has the step and inner sleeve that makes part of the procedure simpler, I believe. But I guess I need to start at the beginning.
What should I look at to be sure I need to replace the bearings, as opposed to service or adjustment (doubtful I could be that lucky).
If they do need to be replaced, how about that preload? Do I need to stock up on shims, wedding bands, spring scales and string? Or is there a simpler way to get "close enough" but still acceptable?
Any and all advice will be appreciated.
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I agree with you that there is too much fuss about setting wheel bearing pre-load. I use Duane Aushermans shake the wheel method which basically involves torquing the wheel nut while testing for the point at which free play disappears. If you still have free play when the correct torque is applied then it needs a wider wedding band spacer or shim added. If free play dissappers at a very low torque level e.g. 5 ftlbs than you need a thinner wedding band. It's not rocket science and in fact I found it very easy to do a better job than the factory.
https://w6rec.com/the-5-wheel-bearings/
While I understand those who will want to actually measure rotational torque with a spring balance the issue I have with that is the increments between wedding band sizes are simply too big to be that precise and it would be pure luck that a particular wedding band size worked perfectly.
I've never had to change the bearings so someone that has can comment but it's simpler than some airheads in that you don't need to remove the whole stack just remove the outer races after heating the wheel.
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Thanks for that, Barry. And I'm glad to hear that you advocate the simpler version. Duane's article was the last one I read before I gave up last night so I'll go over it again today with a slightly clearer head.
As for the wedding bands - is it normal for these to need to be changed over time (from wear?)? Or is it usually when you put new bearings in that they will need to be changed?
And I've seen the package available through Scottie with shims and such. Is that something I should have on hand? I've got no clue as to how many I might need to try to get it correct. It sounds like it shouldn't be too far off if it was previously setup correctly?
Thanks
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The wedding bands don't wear because in use they are clamped tight.
What I found is exactly what Duane wrote about i.e. grossly too much pre-load from the factory so I needed to add a shim (from memory 0.004") which was something I made myself.
In your case you have too little pre-load so you need a thinner wedding band or alternatively you could lap the wediing band to make it thinner. It realy depnds how much needs removing. If you only have slight play it might only need 0.001" lapping off.
The first thing would be to look and see what's in there as somebody may have added a shim which could be removed. On a front wheel that's only a 10 min job and you could inspect the outer bearing race at the same time. From the factory the wedding bands are on the left hand side of the wheel. You will need a tool to remove the bearing seals without damage or new seals. In the absence of the correct tool it can be done using an open ender spanner of the right size.
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Great, that will give me a starting point. Thanks again, Barry.