need help...simple task turned hard...

[plexiform]

77 R100s rear shock relacement....I thought this was supposed to be easy...

All i wanted to do was change out the rear shocks of my 77 R100s and after getting the right side done i started the left and found that the bolt holding the bottom of the rear shock was put in from the inside out.... Now to get it off i have to slide it out but the disc brake rotor gets in the way. I'm not a mechanic, never taken the rear wheel off before and its becoming a real mess.

1. All I really want to accomplish is move the rear wheel far enough off center to get enough room to pull out the lower rear shock bolt (left side).

2. I've wiggled the wheel every which way but cannot accomplish #1.

3. Now that I have the wheel half way off I can't put it back together because of two reasons:
i. the piece that sits inside the wheel hub between the wheel and the shaft side of the swingarm keeps moving off center so i can't get the axle through all the parts it needs to go through, but before i can even get to this i have the next issue:
ii. brake caliper is shut closed and i can't separate the brake pads to get the caliper back in place. I did not try to pull them apart as i figured that was not a good idea. The caliper brace is one of the parts that the rear axle goes through. Any help would be appreciated.

follow link for pics.

http://photo.net/photodb/folder?folder_id=1083163

 

[20774]

I don't have a rear disk on my /7, so I can't go out and look at a similar setup. But seems like you want to get the rear wheel removed which brings the disk with it...that should give you enough room, right?

As for the brake pads being squeezed together, you can very carefully pry them apart. What would be best is to remove the top of the rear brake fluid reservoir...don't let brake fluid spill out. Then, with some wooden shims or maybe a plastic putty knife, slip it between the two pads and separate them. With the cap off the reservoir, there shouldn't be much back pressure. You might be able to use your fingers/fingernails to move the pads apart.

Once you get them enough apart, replace the reservoir cap, and work to slipping the wheel back in place so the axel can be inserted.

I'm not sure where you are in the process of replacing the shock.

 

[pglaves]

Back in 1977 even the itty-bitty riders manual covered the removal of the rear wheel - a skill required in the event of a flat tire with the tube-type wheels. Unless, of course, the rider's recourse for a flat tire is a flatbed tow truck and credit card.

The part that keeps getting in the way of the axle is the arm on the brake caliper that anchors around the axle. This is an agglomeration of pesky parts that don't often cooperate.

Yes - the pads need to be spread to allow the disk to be inserted between them and this must happen before the caliper can possibly line up to allow the axle to be reinstalled.

My advice would be to get the instructions for wheel removal and do it. Then do the shock. Then reinstall the wheel. It will be great practice for the next flat tire.

 

[plexiform]

Bike did not come with user manual. My Clymer manual was ordered last night....will be a few days before I get it. Thanks for the responses. Will continue to try to get the wheel off completely and learn a few important lessons here.

 

[brewmeister]

Hi,can you find a airhead guy in the anonymous book near you? I went through the same thing a few weeks back and showed garlic head how to line up the things you speak of while showing him how to change his tire. He now knows much more on how to do that in the future.I'd come over but you are way to far away from my place to help. I do better showing something like this than trying to adequately explain it to you. But that's just me.Good luck to you sir. What Paul said.

 

[Friedle]

simple task

IIRC, the 77 S had a drum rear brake, the 78 S had a disc brake. You should first be sure of what model and year you have before attempting any maintenance. Owner's manuals are still available from the dealer or on line.

Have you joined the Airheads Beemer Club yet? They are a national organization dedicated to the well being of the Type 247 BMW motorcycles and are very strong in California. They have a lot of hands on Tech Days and lots of members always willing to help another member.

Friedle
NY Airmarshal
ABC Board of Directors, Region 4

 

[plexiform]

I have joined airheads.org and I looked on ibmwr.org for local mechanics and no one near me. I'll look at the anonymous book. I'll keep trying...gotta have someone nearby! I learn much better by seeing than reading but hoping the clymer manual will be user friendly. Will look online for old manual. And yes it's a 77 R100s with rear disc conversion. Checked the vin# and production date which was july1976.

 

[lkchris]

IIRC the bolt in question is supposed to be installed with the nut on the outside.

In addition, it was originally a pretty special bolt in that it's a really fine thread. NOT the same thread as the bolt at the top of the shock.

Also again IIRC both the bolt head and the nut are something like half as thick as usual bolt heads/nuts--providing clearance.

I suspect your problem is caused, then, by operator error, i.e. use of nonfactory parts or perhaps just failure to "convert" everything that required converting. Lots happens to these bikes in 40 years, obviously.

 

[plexiform]

Eventually the plan is to figure out all those conversions/upgrades and learn how to do them myself. Seems like it will be a pretty tall task. But not in a rush and am eager to learn. Appreciate the responses.

 

[plexiform]

I called a local member and he rode his bike down from Paso Robles and helped get the wheel off. Thank you very much Roger. Shocks replaced. Now need to get it back together which I think I can get done myself. Ended up having to take the rear disc rotor off the wheel and then the rear wheel came right out. Anyone know what torque is needed when bolting rotor back to rear wheel hub? Needs cleaned and spline/bearings greased. I called the BMW dealer and he said any Moly will do but forum says Honda moly 60. Any thoughts on which grease to use for rear wheel spline?

 

[20774]

Go with the Honda Moly 60...should be easy enough to find.

 

[roncooper]

Honda MOLY 60 has been discontinued. GUARDOG 525 is now the "go to" stuff.

 

[20774]

Right...I forgot about that...it might be possible to still find some on the shelf. The discussion on the K-Bike forum was here:

http://forums.bmwmoa.org/showthread.php?78215-ATTENTION!!!-All-K-bikes-HONDA-MOLY-60-DISCONTINUED

 

[plexiform]

Ordered Guard Dog 525 from beemershop in Scott's Valley....hopefully get it by Tuesday.

While prying apart the brake pads I chipped a small piece of one of the pads. Do I replace both pads, one of them, or just use it since it's a small chip and not going to affect the braking capacity? See picture of the chipped area.

 

[godfather]

I would not worry about it. There is plenty of pad on either side of the chip.

 

[20774]

I agree I wouldn't worry about it...but I might check it every month or so and see that the size of the chip remains the same.

 

[plexiform]

Done!

got its done. Thanks for the help. How do you tighten the rear axle bolt without pulling the bolt through more than it should be?



Here's the finished product: Farley stand also installed during the down time waiting for GD525 grease.

 

[plexiform]

View of other side

 

[20774]

How do you tighten the rear axle bolt without pulling the bolt through more than it should be?

You can't pull it through more than it should be. On the left side, the axle bolt has a shoulder in it that must be drawn tight up to the bearing stack on the left side. From your picture, I would say that the axle bolt hasn't been pulled in far enough...but you have the disk setup...I'm more familiar with the drum rear brake setup.

The pinch bolt on the left side of the swing arm needs to be loose while you tighten the large axle nut. Once you get it tight, then go back and tighten the pinch bolt. You'll need to keep the axle from turning as you tighten the axle nut...the tool kit has a round bar which fits into that open hole on the left of the axle...you use this to stabilize the bolt as the nut is tightened.

 

[plexiform]

axle bolt

Im not sure if its different for a disc brake setup but it seems the more I try to tighten the nut on the right side it just keeps pulling the axle bolt through. Clymer manual doesnt mention anything about this from my initial search. Will keep looking.