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Since you KNOW the bearings were bad and the shaft(s) were not parallel...and what we see is not an accurate indication of the damage, it's your call on what to do next.
I imagine the mate gear - pinion - is in pretty bad shape.
I hope the replacement gears are "nice".
PS. I've seen some bad gearboxes too. Like the very expensive worm drive I managed to get for a giant piece of textile machinery, and the guys on the back shift decided that 10W-30 ENGINE oil was just as good as "30-weight Steam-Cylinder oil". It nade some very interesting noises before it failed.

Pitting of the gears.........
When I found metal on my drain plug after 13 years of finding just black slime, I wasn't content to just say 'oh well' and put oil back in and keep riding it until one day doing something about it only to find the tranny destroyed.
The hardness of the gears is very thin coating so to speak. When it breaks through, it's going to keep losing material at an increasing rate. My 5th gear had similar wear characteristics.

Of course there is cost to consider. There is cost x at the moment and there will be cost X later.

Consider also the miles Ray does. The worn parts could last a long time.
If we use the above as a base for a decision, why open the tranny in the first place?

Latest setback

No input shaft gears available from Moto Bins or the ususal suspects. MB says they've been on back order for several months. Its for an 82 R100, its part number 23 22 1 242 991, the 17.5 degree cut helical input gear for post 4/82 airhead 5 speeds with the "X" marking in stock. They also would instead be willing to sell an entire input assembly for over $300US...I'll have to pass on that one.


I hope to start calling around in the rare chance someone has on the shelf. Last resort (ugh) is to try to find a good used input gear.

I'm just posting this so people who tackle this type job in the future would be able to search and finad out that not all the frustrations of this type project are technical in nature.

If I'm reading your post correctly Ray and the x gear is in stock, can't you upgrade both input shaft 5th and layshaft 5th to the later x gears?

What part numbers are you looking for? I see this on ebay: http://www.ebay.com/itm/BMW-Motorcycle- ... 4f&vxp=mtr

If I'm reading your post correctly Ray and the x gear is in stock, can't you upgrade both input shaft 5th and layshaft 5th to the later x gears?

Jeff - My input gear, an X gear was a no brainer-definitely needs replaced. The matching helical gear on the layshaft, the one I showed a pic of, well I really don't want to use it. The pitting looks to me, while in my hand, as bad enough to replace.

Now MBins does have the helical gear from the layshaft. I'll have to use the hydraulic press to pull that one off and put a new one on. MB says the matching "X" input shaft gear, 23 22 1 242 991, is out of stock. I can't find one in the US either. MB says to upgrade to the post-85 inut shaft assy but it blows my budget at over $500.

Tim - the part I need is 23 22 1 242 991. Marko at Re-Psychle pulled apart a gearbox to get me one but it was shot too.

Maybe I need to put out an all points bulletin (APB) - Calling all airheads, I need an input gear for a 4/82 to 1985 gearbox!

What about the taller (+5%) input shaft 5th gear? Is that available? Prolly is.

I put the taller input shaft 5th in my RS and like it a lot.

Google is your friend, there's one available in Georgia. Isn't cheap: http://www.barnsleymotorwerks.com/81gearbox.html

Nope

Although shown on their site, none in stock

I was able to get the new input gear from Nathan. He had one on the shelf.

I'll let yall know how it this thing turned out once the parts all come in and I get the box back together

Thanks for all the comments & help