Replacing Drive Shaft Rubber Boot

[Spinachpie]

Hi. I'm sure that somewhere in the Airhead Forum is a link to the procedure of replacing the Drive Shaft Boot (on a '80 R80, etc). For the life of me I can't find one! A little help in the right direction would be greatly appreciated!

(advance apology for possibly missing the obvious thread...)

[CTellman]

This is a time for little fingers. Don't be in a hurry! Finesse is the word.
No shortcuts unless you move FD back for more room.
Campbell Tellman II

[Spinachpie]

Is there a link?

[20774]

Can't say that I've seen such a link. It's just something people do...and sometimes not too well!

I can offer the following:

- the boot has a top and bottom along with a front and back...be sure and get that right.
- not sure where you are in the process, if things are all apart or not. But to make things the easiest, you'll need to undo the four driveshaft bolts and you'll also need to remove the swingarm pins so the driveshaft housing can be moved back 2-4 inches. This requires a special 27mm socket with the leading edge chamfer removed. Plus an allen wrench socket along with two types of torque wrenches, one in the in-lb range and another in the ft-lb range.
- I'd get the rear end of the boot started first and get the clamp positioned
- reattached the swingarm with the proper torquing. Snowbum discusses this on his website; it's in this article

http://bmwmotorcycletech.info/inputsplinesthrowout.htm

- reattached the four driveshaft bolts. New ones are best, clean/dry, blue loctite. I used the 12-point box wrench in my tool kit with a rag in my hand and gave it the best grunt I could. Otherwise there is a special tool to have/make to get a torque wrench on it.
- work on the front part of the boot. This gets to be tough as there's not much room to work. You'll need to find something to help work the boot onto the lip of the tranny. Something that doesn't cut the boot. It can be frustrating.

Do you have a manual? Usually you need one or more manuals to help with this. Haynes and Clymers have manuals.

[Spinachpie]

Thank you. This will be helpful. I have performed this operation once before and have regrettably repressed it deep into the recesses of my mind.

[30064]

S,

Kurt has you well directed from his previous post. The new boot will have seams which should be placed in the 12 and 6 o'clock positions. Your new boot "should" have some markings on it, I've seen some with and without. If you find the words "oben" or the like - that part of the boot should go up or at the 12 o'clock position. The driveshaft housing normally is a bit Asymetrical in shape, as Kurt mentions you may want to start there with a good seal of the boot strap. If you have the bolts with split ring or lock washers, discard them and purchase the shorter bolts. I always replace these bolts, cheap insurance. Details are in Bum's link that Kurt provided. Important thing is you get the connection of the shaft to gearbox output flange snugged equally. I find the torque wrench extension special tool very helpful and makes capturing the bolts easier in such a tight space. Blue Locktite on the bolts. I also stuff a clean towel or rag in the shaft housing and gearbox opening during the bolt and flange attachment just in case a bolt gets away from you. Going fishing for parts inside the housing at this stage will be more of an irritant than the job itself.

[Spinachpie]

Great. I ordered the drive shaft bolt torque wrench adapter from Cycleworks (http://www.cycleworks.net/index.php?...roducts_id=327) and plan on taking my time with this operation. The stretch bolts, rubber boot, and new clamps will be picked up locally at www.streetcycles.com

[MCrenshaw]

See this comment from the microfiche...
"This part is a difficult installation, especially on the paralever bikes, and it is possible to install it upside down and/or backwards. You can use a Sears cotter pin removal tool to install the boot."

If your air intake housing has the bow clips I have found that using one of those to hook into the rubber boot to help ease it over the drive shaft housing can be used with success.

[jforgo]

Some time ago, someone on here said the trick was to remove the shocks, and hold the swingarm straight relative to the transmission output. Fighting that angle is supposed to be what causes the hassle.

[brittrunyon]

Some time ago, someone on here said the trick was to remove the shocks, and hold the swingarm straight relative to the transmission output. Fighting that angle is supposed to be what causes the hassle.

It helps..............

[lmo1131]

Fighting that angle is supposed to be what causes the hassle.

Removing the shocks helps ... alot. But you then have to deal with a swing arm that wants to drop to the floor. No big deal, you just need to plan ahead and find something for it to rest on.

The rear band clamp is the real PITA. BMW could have given us another 3-2mm to work with. Depending upon the fillet weld size, the band clamp may be forced to "jog" around it; not good. Pay close attention to how your set looks before you disassemble it.

With regard to "the special tool"

Your u-joint will more than likely look like this (note relieved portion for socket clearance).



If it looks like the one below (like mine...), with no relief, the tool will not fit (wall thickness is too great), but the 12pt box wrench in the tool roll will.