List of parts for tranny rebuild

Discuss all things 1970 & later Airheads right here.
DonW
Posts: 103
Joined: Fri Aug 06, 2010 4:25 pm
Location: NorCal- near Walnut Creek
Contact:

List of parts for tranny rebuild

Post by DonW »

Yikes- It's been so long since I've read or posted here. I wonder if anyone remembers me :oops:

Anyway, finally going to rebuild 1 or 2 of the 3 trannies I have in the garage. I've done it 2-3 times in the past, but it's been a long time. Wondering if anyone has:
1) a quick reference list of the bearing and seal #'s
2) Source for the bearings (i think i got my bearings and shims from Ed Korn last time, or maybe Hucky's, or maybe a local bearing supply).
3) I seem to remember replacing the little nylon shift wheel with a metal one from a K-Bike. Anyone know?
4) Do folks still automatically replace the pawl spring?

Thanks all,

Don

'92 R100GSPD
(sold both my ST's, the RT, the R65, and the R100)
'04 R1150RTP
'83 R80ST
'92 R100GS
'04 R1150RTP
garage full of airhead parts...
User avatar
Jeff in W.C.
Posts: 1506
Joined: Tue Aug 03, 2010 9:20 am
Location: Walnut Creek, CA

Re: List of parts for tranny rebuild

Post by Jeff in W.C. »

Hi Don,
I can't help you with the list, but I thought I'd say hi.
Jeff in W.C.
1988 R100 RT
2018 R1200 GS
"I've got my motorcycle jacket, but I'm walking all the time." Joe Strummer/Clash
Deleted User 62

Re: List of parts for tranny rebuild

Post by Deleted User 62 »

Hucky has kits with all the bearings and seals needed: http://www.bmwhucky.com/007523.html
DonW
Posts: 103
Joined: Fri Aug 06, 2010 4:25 pm
Location: NorCal- near Walnut Creek
Contact:

Re: List of parts for tranny rebuild

Post by DonW »

Thanks guys, and Hi Jeff (long time, no see!).

I probably don't need all bearings, but will know more when I look closely. Anyone have a suggestion on the little shift mech wheel?

Don
'83 R80ST
'92 R100GS
'04 R1150RTP
garage full of airhead parts...
User avatar
Ken in Oklahoma
Posts: 3182
Joined: Tue Aug 03, 2010 5:10 pm

Re: List of parts for tranny rebuild

Post by Ken in Oklahoma »

Here's a link that has a lot of info on overhauling transmissions, including a list of bearings and seals for both 4 speed and 5 speed transmissions:

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




Ken
____________________________________
There's no such thing as too many airheads
ME 109
Posts: 7307
Joined: Tue Aug 03, 2010 3:00 am
Location: Albury, Australia

Re: List of parts for tranny rebuild

Post by ME 109 »

It makes no sense to not change all the bearings while in there. 89 pounds for all bearings from Motobins.
Complete gasket and seal kits from Motobins as well.
Re the nylon wheel change, I was going to change for the bearing option until someone mentioned that they had used the bearing and didn't like the 'feel' of it. I think I can grasp what the person was saying.....and renewed the nylon wheel instead.
Lord of the Bings
Dave Backmarker
Posts: 58
Joined: Tue Aug 03, 2010 1:16 pm

Re: List of parts for tranny rebuild

Post by Dave Backmarker »

Don,
Six bearings in all (one on each end of: input, layshaft and output), flange seal, output shaft seal, case gasket and a few o-rings plus several shift mechanism plastic bits and the return spring in for the shift mechanism. A great source of parts and tools is Dan at http://www.cycleworks.net Dan also carries an instructional video with numerous great tips. I also picked up an infrared thermometer that allowed me to bring the case up to 150 degrees F for dis-assembly and assembly. A key tool that Dan stocks are two parallel bars and the shim measuring plate. And, the flange removal tool is a must to get that monster loose. My favorite description of rebuilding the airhead transmission was that you require the skills of hand to hand combat plus neurosurgeon. There are a couple of bolts that are VERY tight and then setting the shaft end-play is quite delicate.

If you discover broken dogs or broken gears, please note there are a number of different transmissions with different helical gears (7.5 degrees vs. 15 degrees) as well as different sizes and number of teeth.

DaveM
1975 R90S
2000 R1100RT
DonW
Posts: 103
Joined: Fri Aug 06, 2010 4:25 pm
Location: NorCal- near Walnut Creek
Contact:

Re: List of parts for tranny rebuild

Post by DonW »

Well, believe it or not, I'm resurrecting this thread. I have put it off and put it off, but now have 3 transmissions apart, and on my bench. I have nearly all the replacement parts (bearings, seals, gaskets) on hand.

One remaining question is which springs to replace on the shift mechanism. It looks like there are 3 springs, but I think the last time I did this I only replaced the pawl spring.

Advice? Part numbers? Recommended supplier?

Thanks,

Don
'83 R80ST
'92 R100GS
'04 R1150RTP
garage full of airhead parts...
ME 109
Posts: 7307
Joined: Tue Aug 03, 2010 3:00 am
Location: Albury, Australia

Re: List of parts for tranny rebuild

Post by ME 109 »

The camp is generally split on replacing any of the springs in the shift mechanism.
Due to reported premature breakages of new springs, some advise to let sleeping dogs lie.

I left the original springs in my recent tranny rebuild.

Maybe ask on adv airheads as well, where there is a lot more experience with said springs.
Lord of the Bings
Deleted User 287

Re: List of parts for tranny rebuild

Post by Deleted User 287 »

Hey Don, do you want a burnt out gearbox to experiment with?
Yours for the price of shipping (what the hell, I'll split the cost with you!). I'm not even sure if it is still serviceable. (Google "rob needs a new brain")
The drain plug fell out on me (or something) and I ran it in 5th gear for a while until I got off the interstate. When I went to downshift I knew something was not right...

It could be a good ribbed case, some of the gears might still be good, but mostly I am just looking for someone to perform an autopsy with pictures. :)
Post Reply