Measuring gearbox end-play - Page 2

DiabloADV · 06-04-2012, 12:06 PM

While there is a long trail of tears around no-circlip problems, I've yet to come across an archive of owners complaining that the 0.05mm axial play clearance of the gearbox shafts is causing people's RTW trips to come to a halt. Perhaps maybe they got that one right.

Besides, given the shim sizes they made available (when they were all available), the 0.05mm figure obviously has some play in it as well. A little more; a little less. Probably OK. I'm shooting for a fit in the 0.05mm to 0.10mm range since shims are not available in an infinity of sizes.

supershaft · 06-04-2012, 01:12 PM

Quote:

Originally Posted by DiabloADV

Yes...and I know exactly who....

The engineers at BMW that decided that 0.05mm was the right number.

They get paid to think about such things.

Where did they say that? Everywhere I have looked they said 0 - .1mm. You can usually get it a lot closer to zero if you stack shims. That is if you want to.

bmwrench · 06-04-2012, 08:37 PM

Quote:

Originally Posted by supershaft

Where did they say that? Everywhere I have looked they said 0 - .1mm. You can usually get it a lot closer to zero if you stack shims. That is if you want to.

In a Service Bulletin about 1985. I suspect it was needed with the 17.5 degree gears.

supershaft · 06-04-2012, 09:34 PM

I don't remember that one. Never seen it mentioned in other manuals. I wonder what their reasoning was? I know from experience that less works just fine on the later PFA gearsets. I wish I could read that one. Somebody around here knows how to look them up. I believe trannys are in group 23?

Olliew72 · 01-22-2013, 09:00 PM

Well I'd just like to say that I tried this solder trick for measuring the end play and it worked perfectly. I just wish that I was smart enough to have thought of it myself. I'm glad I stumbled on this thread. Thanks.

ME 109 · 01-22-2013, 11:34 PM

Well then, after my recent tranny rebuild using a shim plate, I've more confidence in the solder method.
What diametre solder did you use?
If you took just .05mm from your solder thickness, and your input shaft spun freely after assembly, it would suggest that my concerns of the solder distorting the cover (and ultimately giving a tighter clearance than thought) are groundless.

a_bakla · 01-23-2013, 01:36 AM

My Rosen core wire was tin and had space at the center. This tin was soo soft that I can even bite and shape it.IMO this type solder wires cant distort the cover.The cover is designed to handle much more force to be able to function.

mendoje · 01-23-2013, 07:02 PM

Can you post the exact brand and part no. of the solder you used? I'm suggesting this so that if we all use it as part of a standard procedure, we can get consistent results.

Thanks!
Jeff

Quote:

Originally Posted by DiabloADV

Today, I tried a method I'd read about. Place little pieces of hollow-core solder so the ends sit across the outer races. Heat the cover and install and torque. Then take the cover back off. Measure the squashed solder, subtract 0.05mm, and you have your shim specs.

It worked perfect, and took 15 minutes instead of the tedious afternoon of ultimate failure. Plus you don't need a $70 flat plate and a $100 indicator. Or much skill.

supershaft · 01-23-2013, 07:23 PM

As I have said a while back, any solder I have around is soft enough. I just thought that I would be concerned with the solder being too soft as far as measuring your clearance with the oil baffles on the bearings. The solder might not be hard enough push them down all the way. Oh well, loose doesn't hurt a thing as far as I can tell. Too loose does from what I can tell. Like I said earlier, I think they shift slightly better set up as tight as possible but, then again, I shift my airheads way more often than anyone I have ever ridden with.

I set up all my tranny work including my own setups without the paper gasket. I have never had a problem for it and I do think it is easier to nail the clearance if that is what you want to do. I use Durko there. Actually, I think they hold oil better without the gasket myself.

2VEZR25 · 03-14-2013, 07:21 AM

For those with transmission experience: As a guide and after all calculations; What would be the typical measurement range of shims (min/max) before being alerted that either a calculation or something internal is not right?
Thanks.

ME 109 · 03-14-2013, 12:27 PM

Quote:

Originally Posted by 2VEZR25

For those with transmission experience: As a guide and after all calculations; What would be the typical measurement range of shims (min/max) before being alerted that either a calculation or something internal is not right?
Thanks.

For me, it was .85 - .95mm

Bigrider · 03-14-2013, 02:16 PM

I have taken apart two five speed trannies. After the first one I was given some advice to measure the clearances of the tranny with original shims right after taken off the cover before removing anything. This will give you a ballpark figure for what the whole system should measure once you get everything back together, generlally within a few thousands. Any gross difference may indicate the pieces weren't seated fully. Another tip was to place new shims on a flat piece of 800-1000 grit sandpaper and lightly snad to take off any burrs that may throw off the measurements even by a little bit.
Dave H
San Antonio, TX

supershaft · 03-14-2013, 07:50 PM

IMO, I wouldn't use what was in there as a guide. A lot of them I have worked on were set up more than a couple of thou on the loose side. Tons of them were shipped that way. They work fine that way but I do think they work better set up tighter. I think that loose end play has something to do with some bearings walking on later snap ringless trannies while others don't but that is really another story. That and I put them back together without the gasket. I know quite a few that do that. Easier to nail the shimming and they tend to leak less without the gasket IMO.

06-04-2012, 12:06 PM	#16
DiabloADV ^OP Semi-Occasional Joined: Oct 2010 Location: Nor Cal, USA Oddometer: 1,534	While there is a long trail of tears around no-circlip problems, I've yet to come across an archive of owners complaining that the 0.05mm axial play clearance of the gearbox shafts is causing people's RTW trips to come to a halt. Perhaps maybe they got that one right. Besides, given the shim sizes they made available (when they were all available), the 0.05mm figure obviously has some play in it as well. A little more; a little less. Probably OK. I'm shooting for a fit in the 0.05mm to 0.10mm range since shims are not available in an infinity of sizes. __________________ '74/'70 R98/6/GS Traveling Bike (construction under way) '91 Bill Holland Steel w/Dura Ace

01-22-2013, 09:00 PM	#20
Olliew72 n00b Joined: Mar 2011 Location: Portland, OR Oddometer: 8	Well I'd just like to say that I tried this solder trick for measuring the end play and it worked perfectly. I just wish that I was smart enough to have thought of it myself. I'm glad I stumbled on this thread. Thanks. __________________ 1970 BMW R75/5 (Came as a free box of parts)

01-22-2013, 11:34 PM	#21
ME 109 Studly Adventurer Joined: Jun 2009 Location: Albury Australia Oddometer: 605	Well then, after my recent tranny rebuild using a shim plate, I've more confidence in the solder method. What diametre solder did you use? If you took just .05mm from your solder thickness, and your input shaft spun freely after assembly, it would suggest that my concerns of the solder distorting the cover (and ultimately giving a tighter clearance than thought) are groundless. __________________ Lord of the Bings

03-14-2013, 07:21 AM	#25
2VEZR25 Recuerde el 911 Joined: May 2012 Location: C.A. USA Oddometer: 52	Shim stack range For those with transmission experience: As a guide and after all calculations; What would be the typical measurement range of shims (min/max) before being alerted that either a calculation or something internal is not right? Thanks.

Thread Tools	Search this Thread
Show Printable Version Email this Page	Search this Thread: .
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

06-04-2012, 09:34 PM	#19
supershaft because I can Joined: Sep 2010 Location: San Francisco Bay area Oddometer: 6,068	I don't remember that one. Never seen it mentioned in other manuals. I wonder what their reasoning was? I know from experience that less works just fine on the later PFA gearsets. I wish I could read that one. Somebody around here knows how to look them up. I believe trannys are in group 23?

01-23-2013, 01:36 AM	#22
a_bakla A&F Joined: Oct 2009 Location: Turkey,Tekirdağ Oddometer: 68	My Rosen core wire was tin and had space at the center. This tin was soo soft that I can even bite and shape it.IMO this type solder wires cant distort the cover.The cover is designed to handle much more force to be able to function.

01-23-2013, 07:23 PM	#24
supershaft because I can Joined: Sep 2010 Location: San Francisco Bay area Oddometer: 6,068	As I have said a while back, any solder I have around is soft enough. I just thought that I would be concerned with the solder being too soft as far as measuring your clearance with the oil baffles on the bearings. The solder might not be hard enough push them down all the way. Oh well, loose doesn't hurt a thing as far as I can tell. Too loose does from what I can tell. Like I said earlier, I think they shift slightly better set up as tight as possible but, then again, I shift my airheads way more often than anyone I have ever ridden with. I set up all my tranny work including my own setups without the paper gasket. I have never had a problem for it and I do think it is easier to nail the clearance if that is what you want to do. I use Durko there. Actually, I think they hold oil better without the gasket myself.

03-14-2013, 02:16 PM	#27
Bigrider Living the Legend Joined: Apr 2005 Location: 76 R90/6, 84 R80RT, 84 R100RS Oddometer: 11	I have taken apart two five speed trannies. After the first one I was given some advice to measure the clearances of the tranny with original shims right after taken off the cover before removing anything. This will give you a ballpark figure for what the whole system should measure once you get everything back together, generlally within a few thousands. Any gross difference may indicate the pieces weren't seated fully. Another tip was to place new shims on a flat piece of 800-1000 grit sandpaper and lightly snad to take off any burrs that may throw off the measurements even by a little bit. Dave H San Antonio, TX

03-14-2013, 07:50 PM	#28
supershaft because I can Joined: Sep 2010 Location: San Francisco Bay area Oddometer: 6,068	IMO, I wouldn't use what was in there as a guide. A lot of them I have worked on were set up more than a couple of thou on the loose side. Tons of them were shipped that way. They work fine that way but I do think they work better set up tighter. I think that loose end play has something to do with some bearings walking on later snap ringless trannies while others don't but that is really another story. That and I put them back together without the gasket. I know quite a few that do that. Easier to nail the shimming and they tend to leak less without the gasket IMO.