ME 109 has inspired me.

[Garnet]

It's not that expensive: http://www.cycleworks.net/index.php?mai ... ucts_id=39

To me it's a mater of finding the most accurate method of measurement. Since (for me) it is a single use tool, it would be nice to share one.

[ME 109]

It's not that expensive: http://www.cycleworks.net/index.php?mai ... ucts_id=39

To me it's a mater of finding the most accurate method of measurement. Since (for me) it is a single use tool, it would be nice to share one.

That's right Garnet. The cost of a shim plate pales into insignificance for me, compared to what I've spent on this bike.
Hey, come on over and share my plate!
Charlie could come over and we could discuss end float to the enth degree.

I've managed to find enough time to just measure the thickness of the shim plate.
Maybe this evening I will get a chance to progress.

Oh yeah, the plate measures 19.04mm/.7496 inch. Sort of a ball park figure.
That's a start.

[Major Softie]

I've managed to find enough time to just measure the thickness of the shim plate.
Maybe this evening I will get a chance to progress.

Oh yeah, the plate measures 19.04mm/.7496 inch. Sort of a ball park figure.
That's a start.

Since the plate is only flat within .0004", I'm not sure you should be quite so confident about your precise measurements. On something built to such sloppy tolerances, you'd better measure the thickness in 30 or 40 random spots and record each.

[Ken in Oklahoma]

How much does the proper tool (plate) cost? Within a given country, I would think they could be shared, somewhat. As in, someone needing to use one would pay a portion of the cost, much like a rental, to the person who had stepped up and bought one. Say, maybe 20% of the cost of buying the plate.

If Duane Ausherman were watching the forum regularly I reckon he would already have chimed in with his often recommended method for easily making a good cheap gage plate. Take a transmission end cover to a vertical mill and you can make the gage plate you need. The raw material, a transmission end cover with a broken off ear for the cable-to-push-rod rocker, may be a bit difficult to find.

To make the gage plate you clamp the transmission end cover face down onto the milling machine table. Then you mill it away until you expose all of the bearing cavities for the transmission shafts. Then you need to sand or scrape or file away the bearing journals until the bearings are a slip fit. That way you don't have to heat up the the new gage plate to install it onto the back of a transmission.

Duane then stamps the thickness number on the plate itself, so he only has to measure it once.

By measuring the thickness of the milled-away cover with a micrometer you know precisely how thick the reference plate is. Now you can measure how much each bearing protrudes past the cover and use that figure to compare against the depth of the holes in your good cover. From there you can calculate the shim stack needed for each bearing.

If somebody wants to bring a bad cover to the May Boxerworks rally at my place we can put it on my mill/drill machine and mill down the cover. Scrape away the bearing journals a bit and you're good to go.

As an aside I nearly created a bad cover plate myself after replacing the clutch on my '77 R100/7. I took it out for a ride and all was well. Then, strangely, all of a sudden I got a lot of extra slack in the cable. Stopping to take a look at things I then noticed that the pin going through the two cast ears on the cover plate had lost its circlip, dropped partly out, and then only one back plate ears was engaged. This is the classic way that bad back covers are created.

Having been bit once I then made up some special bolts to use instead of the factory set up. Finding 8mm (I think) bolts with an unthreaded part long enough, I lopped off the excess threads and used a nylock nut to secure the pin in place.



Ken

[ME 109]

I've managed to find enough time to just measure the thickness of the shim plate.
Maybe this evening I will get a chance to progress.

Oh yeah, the plate measures 19.04mm/.7496 inch. Sort of a ball park figure.
That's a start.

Since the plate is only flat within .0004", I'm not sure you should be quite so confident about your precise measurements. On something built to such sloppy tolerances, you'd better measure the thickness in 30 or 40 random spots and record each.

No precision here Major I did measure the plate all over.......too many times. 19.04mm average according to my eyes.
The plate is nominally 3/4" plus or minus .005" according to cycle Works.
There are varying measurements of the pockets in the cover. There are varying measurements from the plate to the bearings.
This is art, not science.

[hzbloke]

I'm a simple soul and in no way an expert on rebuilding gearboxes. But I did mine 30,000km ago (with virtually zero clearance) and it works beautifully. I'm beginning to believe that there is too much thinking going on around here.

I really like mogas' just-get-in-there-and-do-it attitude but, like several others, I have doubts about using solder. I have no doubts, however, that if your end cover is not flat then you need to lap it until it is. A sheet of glass and valve grinding paste works beaut.

I'm fairly certain that it doesn't matter a rats if your shim plate is flat or all the same thickness. It could be cornflake shaped and it wouldn't matter. As long as you know the thickness at the spot where you are taking your measurements from for each shaft (your sheet of glass could be useful here) and you put your measuring device on exactly that same spot every time then it will give you the figure you need to do your clearance calculations.

Don't bother getting someone else to check your measurements (but do get them to check your maths) as everyone has a different 'feel' when it comes to micrometers and such. Do check your own measurements many times.

Don't forget to include the gasket in your calculations.

Do remember that we are doing this for fun.

Cheers
Ray

[Major Softie]

Oh crap - now it has to be fun too!

[ME 109]

I'm beginning to believe that there is too much thinking going on around here.

There is Ray, but it's a way to gain understanding of what is required to achieve a suitable outcome, by people who have not done this before. Me
The outcome of getting it wrong is expensive and frustrating.
The biggest problem is achieving the extremely fine tolerances specified. I'm sure there are plenty of failed tranny repairs out there.

For me, complicating a theoretically simple procedure of measuring shim size, is the fact that even with a very accurate shim plate, I'm getting variations across one bearing which are greater than the specified clearance tolerances.
That does tend to make things a little difficult.
I've taken scores of measurements around all of the bearings, inner race, outer race, multiple positions.
I've tried different measuring techniques with the depth gauge, always ensuring firm pressure of the gauge on the plate.
I need to go and remeasure everything.

FWIW, my measurement calculations for shims thus far, including .05mm end play are......................

Output, 1.026 mm

Input, .949 mm

Lay shaft, .899 mm

All the above measurements seem too big.

Back to the Mitutoyo depth gauge (thanks Ray )

[Deleted User 287]

Don't forget to include the gasket in your calculations.

I know something else not to forget!

[Ken in Oklahoma]

There is Ray, but it's a way to gain understanding of what is required to achieve a suitable outcome, by people who have not done this before. Me
The outcome of getting it wrong is expensive and frustrating.
The biggest problem is achieving the extremely fine tolerances specified. I'm sure there are plenty of failed tranny repairs out there.

For me, complicating a theoretically simple procedure of measuring shim size, is the fact that even with a very accurate shim plate, I'm getting variations across one bearing which are greater than the specified clearance tolerances.
That does tend to make things a little difficult.
I've taken scores of measurements around all of the bearings, inner race, outer race, multiple positions.
I've tried different measuring techniques with the depth gauge, always ensuring firm pressure of the gauge on the plate.
I need to go and remeasure everything.

. . .

Nice answer, ME109. Thoughts I've not thunk.



Ken