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thanson
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I went through my final drive to replace all the seals on my 57 R60 (did not replace any bearings), I checked pinion depth, ring gear backlash as well as float. I did have to swap out shims for float adjustment...the other two were fine.

I know I'm not the only one who has ran into this before and even the Barrington manual says to give it a couple good smacks on some 2x4" boards if the final drive is stiff to turn by hand. I did give it a few good smacks when the cover was still warm and it turns nice and easy (while warm) but as soon as it cools down I can't turn the pinion by hand...I have to use pliers.

I heated up the cover to 180 degrees like the manual states and used a modified aluminum can to cover the splines to protect the cover seal and prevent it from twisting.

I did use a bit of grease to hold the float shim in place.....maybe its a bit tight due to that grease and will loosen up when I start riding it again? Any other thoughts?

malmac
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Toowoomba, Australia
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not that I know much

I have only rebuilt one final drive - but do have one sitting waiting its turn for a rebuild.

A question or two - were the shims you replaced on the crown wheel or the pinion gear?

On the assumption the final drive is not back on the bike - is there any backlash at all in the final drive now?

If there is backlash, however small - does it seem greater when checking the input pinion shaft Vs the output spline?

This might tell you that the crown wheel is too stiff and the pinion shaft is about right.

The other thought is - did you try and take all the wear out by adjusting just the crown wheel and not making a slight adjustment to the position of both gears.

Or maybe the shim you put in was just a fly shit too big - and it sucks but you may have to replace with a slightly thinner shim.

Like I say just some thoughts - which might trigger something in your mind that helps you address the issue.

Regards

Mal

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mal - R69s
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thanson
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.

malmac wrote:

I have only rebuilt one final drive - but do have one sitting waiting its turn for a rebuild.

A question or two - were the shims you replaced on the crown wheel or the pinion gear?

On the assumption the final drive is not back on the bike - is there any backlash at all in the final drive now?

If there is backlash, however small - does it seem greater when checking the input pinion shaft Vs the output spline?

This might tell you that the crown wheel is too stiff and the pinion shaft is about right.

The other thought is - did you try and take all the wear out by adjusting just the crown wheel and not making a slight adjustment to the position of both gears.

Or maybe the shim you put in was just a fly shit too big - and it sucks but you may have to replace with a slightly thinner shim.

Like I say just some thoughts - which might trigger something in your mind that helps you address the issue.

Regards

Mal

The shim I had to swap out for float (that sits on the large bearing on the backside of the ring gear).

I can wiggle the pinion back and fourth a bit (.....and can not even budge the ring ring gear. That does tell me the problem is the ring gear is too tight. I'm not sure how as I followed the book as exact as I could and triple checked all my measurements. Maybe that light layer of grease I put on the shim is what's causing the problem?

malmac
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I know it sucks but

I know how frustrating it is when you think you have been as careful as you can be and you end up in a bind like this (pun intended).

However I know I would pull the thing apart and get it right, rather than run it and hope for the best - mistakes can be so very expensive.

The problem I see is that large spacer/shim sits between the alloy cover and the bearing - and when something is forced to turn because the engine is stronger than the friction between the spacer and the alloy case - it will the alloy case that is chewed out - the wrong spacer will not suffer - as you can see I am a chronic optimist (I'm kidding of course) - however it does make some sense.

I just completely cooked a rear engine bearing - went a beautiful dark blue - because I misjudged the electric hot plate - so errors happen - I believe yours hasn't happened yet - because no permanent damage has been done - maybe just a bit of time traded for experience.

All the best with your problem.

Mal

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mal - R69s
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thanson
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I hear ya, I have removed

I hear ya, I have removed the cover 3 times now.....every time I reinstall I have to wait for it to cool down before checking.

It still bothers me that my math didn't work....I don't understand what is wrong

I used the Barringtons final clearance of .010 instead of BMW's final clearance of .002. Even though my new cover gasket seems to be the same thickness if not a little thinner than the old gasket and yet I still have a tight final drive.

Twocams
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i just put in one new seal

i just put in one new seal and checked the gears inside. It was real stiff to turn and I did the old 2X4 trick and slammed it down pretty hard. turns easy enough by hand now. But mine was fairly kool by then.

Rich

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Twocams
69 R69S 03 K1200GT
92 R100RT

thanson
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Just put the stock shim back

Just put the stock shim back in, reassembled, let cool completely after giving it a few good wraps against a couple 2x4's.....it turns easy by hand again.

malmac
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Toowoomba, Australia
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Glad to hear it is working out

Sounds good -

I hope mine goes together well in due course.

Mal

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thanson
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As I am still new to

As I am still new to driveshaft bikes I have a question about heat. Should there be some heat to be expected from the final drive?

I got everything back together and after double checking all fasteners/fluids ect....I took the bike for a little 10 minuet ride down the street. Listening and feeling for anything odd.

It seemed to feel ok the only thing I noticed was a bit of a wine from but I'm sure that's to be expected from a shaft bike. (I'm still used to chain drive bikes)

(By the way I also replaced front and rear wheel bearings/adjusted preload ect....)

I felt the front hub and It was cool, I felt the rear hub and It was warmer than outside temp. It was not Hot by any means I guess it was just expecting it to not really be producing any heat. I got out my Infrared heat gun and it said 85 degrees F. The temperature outside was 55 degrees. Is this to be expected. It could also be the new rear wheel bearings causing the heat but I doubt it as I set up preload on them the same as the front. (same method anyway)

I feel I finally got the engine tune down very good as well, nice and smooth idle as well as at throttle. pulled the carb boots off and put my empi sync tools on the carbs to double check and what do you know....they match perfect.

malmac
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Toowoomba, Australia
Joined: 06/29/2014
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I am no expert

This is a 17c rise in temp in a short ride - it does seem a little high given how short the ride was and low the starting temp was.

We also have a 1200gsa and last year towed a trailer around - I was concerned for the rear final drive because of the towing - I am sure it was running at least 15c above ambient temp - however that was over the period of a days ride of many 100's of Ks -

So I would check that your backlash is not excessive - did you blue the contact patch to check that the contact patch was about right?

You could drain the oil and see if there is any contamination>

Also you could try running a full synthetic oil which might have better friction reduction properties.

Also you could use your heat sensor to try and find out if heat build up is greater from different locations.

Also you may just use your rear brakes more than the front ones - or your shoes may be dragging causing heat.

Just a few ideas to consider.

Mal

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mal - R69s
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caker
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Philadelphia area (NJ)
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Brakes convert kinetic energy

Brakes convert kinetic energy into: heat. If you used the brakes, you heated the hub. Need to factor that into the analysis Smile

-Chris

thanson
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I'm sure you are both

I'm sure you are both correct, possibly just heat built up from the brakes. I took another ride today (it was 65 degrees out). I took it for a ride across town and back. Pulling over regularly to make sure nothing is getting excessively hot. by the time i got back I checked temp with a heat gun. Aprox 90 degrees coming from the rear final drive opposed to the the 80 degrees coming from the front hub. I was using both front and rear brakes. Next time I take it out i will do my best to not use the brakes to see if there is any difference. Bummer that there are so many factors (bearings,final drive, brakes)

(Edit: I forgot to mention i replaced front/back brake shoe linings)

After reading a few other threads related to rear differential heat i think maybe i am just being overly cautious and probably making a big deal out of nothing.

Fred Heiler
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Chester Springs, PA
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R60/2 Restoration

I'm midway through the restoration of a 1967 R60/2 that sat for 30 years. Not surprisingly, I'm having trouble removing the rear wheel bearing stack. I've done the usual stuff, including heating the hub to nearly 300 F, and putting it in a press (to six tons), but no go. Any advice?

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Fred Heiler: Chester Springs, PA
1967 BMW R60
1965 Porsche 356 SC, 1986 Porsche 911

schrader7032
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San Antonio, TX
Joined: 10/27/2006
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Duane Ausherman discusses the

Duane Ausherman discusses the process here:

http://w6rec.com/bmw-motorcycle-wheel-bearings-1956-through-84-repair-pr...

The bearing stack only goes out one direction, so be sure it's going the right way.

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Kurt in S.A.
'78 R100/7 '69 R69S '52 R25/2

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