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1978 r100rs rebuild

Snowflake wheels

Right after I bought the '78 R100Rs for a restoration, I also bought an '83 R100/T. The R100/T was somewhat of a basket case, and the rear Snowflake wheel had been removed --- the wheel bearing had seized.

I have the Snowflakes cleaned, powdercoated, and I plan to install them on the '78 R100RS. I have pressed in the bearing races in both wheels and installed the distance spacers with the plastic donuts. Hopefully I can figure out the wedding band spacers and the top-hat spacers.

Look at the picture of the Rear Drum Snowflake. The bearing race presses deep into the hub on that side of the wheel. The distance to the edge is much more than the thickness of the oil seal. Am I to assume that the seal installs flush to the edge of the hub?

I think there is an 18.7mm bushing that installs on that side of the axle. Right?

I did not get to observe how everything fits since the wheel was already disassembled.

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Put the thrust sleeve into the seal, then push the seal flush. Then push the thrust sleeve against the bearing. If none of the sleeve protrudes through the seal, push it in a little farther, until a little of the sleeve does.

For many years BMW has supplied the seals for the left side that are very soft. Rather than trying to tap the seal in, smear it's O.D.with grease and push it in with your thumbnails.
 
Thanks for the info.

I was actually wondering if TWO seals were required. There is certainly enough room for two stacked together.
 
From the BMW service manual, "The sealing rings must be flush with the upper rim of the hub when driven in."

This quote was under a snow flake wheels with disc brakes, but I think the procedure probably applies to both type of wheels since they did not address drum brakes???

Also, remember there has to be room for the wheel bearing too.
 
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1978 R100RS Rebuild

The rebuild has been slow.

It is very hot in the garage. There is only one A/C vent and no return.

Reminder: A/C Project for Fall, 2010 ---- Return and another vent --- or --- separate unit for Garage. Yea, that's the ticket.

At the moment, the frame, front-end, swingarm, rear drive, subframe and wheels will be assembled in my office. It is 76-degrees in there. :)

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1978 R100RS Rebuild

One other thing ---

In another thread, I mentioned getting a new centerstand. I also mentioned that I thought the frame centerstand mounts were not parallel. :banghead

Well, this picture makes it very clear. I will have to heat and bend them back to parallel. These long bolts threaded into the mounts easily show how much they are out of parallel. The mounts may also need to be filled, drilled and re-tapped. The bolts wobble quite a bit even fully threaded into the mount/tang/thang. What would it be called?

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The center stand mounting lugs can be bent cold-your paint job is safe for now. There are a lot of methods for straightening them; I now use a K-Bike or Monolever front axle with a 10mm stud threaded into it. I thread the stud into the stand lugs and use the axle as a prying tool to get them straight. You may need the help of a couple of strong friends. If necessary, I slip a fork tube over the axle for more leverage. If the threads in the lug are weak, you can Heli-Coil them rather than welding and re-tappng.
 
Looking great!

Wow, this is what I can look forward to?? Hope so!
Hey Dap here is a picture of my flywheel and yours side by side: looks like the same mod, but they went swiss cheese on mine...here's a pretty cool thread about it...
http://forums.bmwmoa.org/showthread.php?t=47745
 

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Suggestions for crankcase vent hose

Still working on this rebuild. I now have a somewhat rolling chassis with the snowflakes and front forks / brakes from an '83 R100/T.

I am currently working on getting the electrics back into the engine. New diode board from Rick at Motorad Electrik.

Rebuilt Starter. Newer wiring harness from an '82 R80RT.

The crankase vent hose is disintegrating. Does anyone know a substitute? Just checked at MaxBMW, Huckey's, A & S BMW ---- no one seems to have the original hoses. Any ideas?

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Dap_Spackled said:
The crankase vent hose is disintegrating. Does anyone know a substitute? Just checked at MaxBMW, Huckey's, A & S BMW ---- no one seems to have the original hoses. Any ideas?
Click to expand...

There's Bob's BMW, Ted Porter at the Beemershop. Maybe one of the salvage yards? Although you might get something just as old. A number of used part places are listed in the Links and Resources area.
 
Vent Hose

You might try to find a good business near you that does nothing but hoses...I know from experience that some of them have the ability to make a custom hose like that including the bends and one end being larger that the other. This was deiscovered during my airplane rebuilding days.....
 
I'm reading about your project with great interest as I've just recently acquired an '81 R 100 RS and it's always good to see what may be in my future. I notice you have soon nice non stock pieces on your bike, along with the flywheel you have a nice braced rear swingarm, but I'm curious about your gas tank- that's not stock is it? looks nice though. also curious about front blinkers and handlebars- did your bike lose its fairing along the way? looks like you're doing a great job- continued good luck!

Michael
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'78 R100S '81 R100RS
 
hoses are available

you can find a proper hose at most any auto parts store... Auto Zone or Napa.. just take the unit with you and get new flexable rubber hose and cut it to size.
 
Michael,

This 1978 R100RS will end up being a Heinz57. There were very FEW things original from a string of previous owners. However, I have been thoughtful in selecting components that would enhance three categories: performance, comfort and dependability. I honestly have enought parts to reconstruct an origional R100RS, but that is not my challenge.

I believe the tank is from a /6. However, I also have a /7 tank.

I build bikes that are "near stock" with my personal modifications. We'll see how it turns out. I am anxious to finish this one, and start on the other: an '83 R100/T.

Thanks
 
Flywheel

Whoever did the safety wiring on the first flywheel did not know what they were doing....It is completely wrong. In my experience a properly torqued bolt very rarely comes loose. There is almost certainly a web site where proper safety wiring is shown...The old FAA books AC 43-13 part 1A and 2 clearly show this. Those have been superceded but I do not know what the current numbers are right now. If your are going to use safety wire, it does no good to do it incorrectly....That just gives you a false sense of security. You also need a good quality pair of safety wire pliers...This photo shows the wiring was not done with that tool.
 
Pretty hard to even tell the way they safety wired it.

Oh, by the way, I recently picked up one of those diode boards in a lot of BMW stuff. Is there a way to bench test it, as you can with the original?
 
Cool. That drawing helps.

The PO only drilled and wired a single side of each bolt. They are not drilled through.

I actually had no plans to use the safety wire again. They are now torqued with blue Loctite. That's enough for me.
 
You will be ok, I have never seen a bolt that was in good shape and torqued correctly loosen. I spent 16 years working on military aircraft and we had to safety wire everything per regs.

I am still around aircraft (small personal aircraft) and they also safety wire everything. I see the point, since something like an oil-filter coming off in flight could be a problem. I also see the point in racing applications. But, my bike is 32 years old and the flywheel has not come off yet. No safety wire either.

Keep going on the rebuild, it looks nice.
 
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