R65 transmission clip

[kentuvman]

My son helped get the frozen water to come out of the tranny box by putting a heat lamp underneath her overnight. A bunch of water came out and I found this clip dangling from the drain hole.

Now I know the transmission has some damage and we need to pull it. Can anyone identify this part? The part that looks like a fishing hook (where it forms a "U" is where the clip broke.

Any suggestions appreciated.

Ken in MN

[20774]

Possibly part of the pawl spring. Usually when this breaks, you're stuck in that gear. You can shift the bike, but you first have to turn the bike upside down...:bolt

If it is the pawl spring, the tranny will need to be opened up. #7 here:

http://www.realoem.com/bmw/showparts.do?model=0363&mospid=47851&btnr=23_0268&hg=23&fg=05

[boxermaf]

Though it doesn't happen often, it does happen that the pawl spring (which that might be the end of) for the shifter pawl can break on airhead transmission. When this happens, one often ends up with the transmission stuck in a gear or between gears - which at least sounds somewhat like your situation.

check out this thread in our R65.org technical section on one member's repair/rebuild of his transmission:
http://www.bmwr65.org/cgi-bin/yabb2/YaBB.pl?num=1233267267

You'll see a photo of the inside of the transmission with the rear cover removed - toward the left is the shifter pawl/selector plate and associate linkage with spring. There is another thread that has just these specific items taken apart and shown, but I can't find it at this instant.

[108625]

Can you change gear at all? That looks like part of the notorious pawl spring, which was cleverly designed by superior german engineers to leave the bike stuck in whichever gear it was last shifted into before it broke.

Before you commit to pulling the transmisiion and spending serious $, (that's if you don't need any hard parts beyond bearings, seals, etc), stop and sleep on it. I'd strongly encourage you to thoroughly inspect everything else, drop the oil pan, look at the rear wheel drive splines, and so on. How's the gas tank? They're never cheap, unless it's a gamble. I'd really want to know the engine runs well (you can run it with the transmission off, as long as the clutch assembly is left on) before moving on. You can easily fall into a motorcycle money pit.

[kentuvman]

All good suggestions.

Right now the plan is to have my boys help me go thru the bike as a learning experience. The entry price was 1k - I do know that in the best of times it might be worth 3k running. The good news is everything is there. Bad news could be having to do some major repairs.

I can tell it will take some $$ to get it up to speed - carbs need rebuilding and not sure of motor but will check. Good suggestion to pull the tranny and see if the motor will spin.

Cosmetically, the bike is very cool looking - Henna Red - tanks and everything else is in "B" condition.

Is it possible the transmission will work with a broken Circlip? Since the water came out, the shift lever works but I haven't futzed with it to try to get it into neutral.

[108625]

All good suggestions.
Is it possible the transmission will work with a broken Circlip? Since the water came out, the shift lever works but I haven't futzed with it to try to get it into neutral.

The circlip and the pawl spring are two different things; one causes excessive wear and premature failure, and the latter can break in an otherwise perfectly good transmission and leave it stuck in gear. Odds are, your water filled transmission is no longer perfectly good.
On the optimistic side; this is probably why the bike was parked, and as it's a failure that would prevent riding, one would hope the engine ran well enough before it happened.

http://www.ibmwr.org/r-tech/airheads/openTranny.shtml

[kentuvman]

Good Point, Bob - thanks. Wil keep you posted as I get further into this.

[20774]

Opening a tranny has too many wrenches on the grading scale for me...this is something I'd want an expert to go. But I've run across a couple of websites that provide a lot of details regarding this. Might be enough to decide if this is something you can do.

http://jhau.maliwi.de/mot/gearbox.htm

Another good site with information is Anton's:

http://www.largiader.com/tech/airtrans/

The thing that seems difficult is getting the shimming right. The correct way to do that is using a rear cover designed for this purpose. The first link actually gives the information to have one machined. They also show up on fleabay once in a while.

[kentuvman]

Okay - I know a transmission guy - assuming we break open the case and everything looks good - is the clip that broke easily replaceable? The picture I was just sent below shows what I think is the clip that broke.

[20774]

I don't have a clue as to how to replace the spring. But there's more to consider when you go inside. There's the circlip issue...I forget your model and year...might not apply. There was a shift kit which improved shifting...I believe a new style spring was included with the kit. The kit is NLA but I think pieces can be bought. People like Tom Cutter or Ted Porter would know more of these details. They do this work all the time.

[boxermaf]

Your transmission should have the output shaft circlip (the thing that many worry about not being there) in it - BMW started leaving those out after the shift to putting the R65 engine in the R80/R100 monoshock chassis, sometime after 1986. The part that broke on you isn't that part (and the circlip never breaks), but the shifter road pawl spring (shown in that pic) or one of the springs on the shifter plate linkage do - usually it is the one that goes around the rod as shown in your pic. Unfortunately it does involve significant tear-down. If you ask one of the moderators on the R65 site, he has just finished tearing an R65LS transmission apart and rebuilding/shimming it himself and can probably give you first hand advice on how to do it, or whether you should undertake this yourself or not.

[tghsmith]

pawl spring part yes,causes the stuck in gear, 1981 does not have the improved mech(shift kit)this change started in 83, but you really have to look inside a 83 some had it some didn't. water bad(have to inspect all the internals). transmission guy, does he have the required tool for pulling the drive flange, (this can be purchased cheaper than the average hour of shop time) also required in putting the drive flange back on, search around some very good gearbox pages out on the web, If you can get your hands on the tools needed everthing can go back together in an evening. the old haynes manual had plans on how to make a shipping crate for the gearbox if you didn't have a dealer near you....

[crazydrummerdude]

Right now the plan is to have my boys help me go thru the bike as a learning experience. The entry price was 1k - I do know that in the best of times it might be worth 3k running. The good news is everything is there. Bad news could be having to do some major repairs.

My R90's needed some repairs; new rings, honed cylinders, cleaned pistons, new valves, new valve springs, fresh valve seats bead blasted heads, rebuilt transmission with new gaskets output shaft and new bearings, new steering head bearings and races, rebuilt carbs, rebuilt master cylinder with new piston and seals, rebuilt caliper with new piston and seals, new fork seals, new fork boots, new fork oil change, new engine oil change, new everything else oil change, reworked the headlight wiring harness, reworked the turn signal wiring harness, new bulbs, new points, adjusted the valves, balanced the carbs, new air filter, new oil filter, etc etc..

I'll be registering it for the road within the next couple weeks; after I throw some new tires on it.

I still have less than $3000 in it.. and I could have saved some money along the way.

Good luck.

[RandyB]

My R90's needed some repairs; new rings, honed cylinders, cleaned pistons, new valves, new valve springs, fresh valve seats bead blasted heads, rebuilt transmission with new gaskets output shaft and new bearings, new steering head bearings and races, rebuilt carbs, rebuilt master cylinder with new piston and seals, rebuilt caliper with new piston and seals, new fork seals, new fork boots, new fork oil change, new engine oil change, new everything else oil change, reworked the headlight wiring harness, reworked the turn signal wiring harness, new bulbs, new points, adjusted the valves, balanced the carbs, new air filter, new oil filter, etc etc..


Good Lord. I'd hate to see what you call an extensive rework. Great job and great pics of your bike.

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