Uh Oh...

I just got a disturbing memo from the Transmission Ministry Of The Interior.
And he's NOT happy...




It was time to replace all fluids today. Everything was going great till I washed the tranny plug off in the solvent bath to clear the oil off the magnet. It looked a bit fuzzy and after a bit of rinsing... oh boy. Bad news.

So I guess I'm pulling the gearbox tomorrow dangit.

Which bike?

That would put a damper on your day.

It would appear that the slow but inevitable process of mechanical decay has in this instance - accelerated.

PGlaves said:

Which bike?

Click to expand...

Oops, forgot to mention that. It's my 81 R80G/S that wants help this time. I'm surprised to see this happen at 66K kms which is only 44K miles. The PO had sent the speedo to Palo Alto for repairs when the odometer reset button quit working and told me they set it back to original miles. I am beginning to doubt that claim very much.

I also had to replace the steering head bearings which were fairly hammered but that may have been because they were quite obviously NEVER greased. Other things I have repaired and found on the bike over the ten years and 24K kms I have had it lead me to believe the mileage might be a bit higher than claimed but who knows after 38 years?

In BC I could do a title search that includes mileage at time of sale to new owners of which there were supposedly only two; the original owner and the guy I bought it from. I think they want about 40 bucks for printing out a sheet of paper from their server so I never bothered preferring to trust people instead. Maybe I'm naive?

So the '81 is not within the range of missing circlip transmissions which was about '85 to '94. Is it possible that the transmission is newer than 1981 and is a transplant?

Guess with that kind of spooge on the drain plug, it doesn't look good. You could service the transmission and recheck the drain plug in say 1000 miles and decide what to do then.

20774 said:

So the '81 is not within the range of missing circlip transmissions which was about '85 to '94. Is it possible that the transmission is newer than 1981 and is a transplant?

Guess with that kind of spooge on the drain plug, it doesn't look good. You could service the transmission and recheck the drain plug in say 1000 miles and decide what to do then.

Click to expand...

With only two owners before me and a claimed very low mileage when I bought it ten years ago I highly doubt it is not the original gearbox. Not sure how to even find out if it is a "numbers matching" bike but pretty sure it is. I don't think this one is without the circlip but after 38 years... who really knows until the rebuilder tears into it.

I'm always telling people not to keep riding a known problem and since this is the first oil change that produced any shiny metal at all and a couple of the bits look like bearing cage being torn off I am not going to ride it another mile. It's coming out today and my spare 5 speed gearbox is going in there pronto. Not sure who I will send it to for repair. The original one has a kick-starter; spare does not which is OK as I have never used it. Apparently, post /5 gear boxes kick starters break easily...

Since you're going to open it up, confirm that it has the circlip. Snowbum has been keeping lists of bikes that are clip-less here:

https://bmwmotorcycletech.info/transmission.htm

20774 said:

Since you're going to open it up, confirm that it has the circlip. Snowbum has been keeping lists of bikes that are clip-less here:

https://bmwmotorcycletech.info/transmission.htm

Click to expand...

Not too sure what I'm going to do with it just yet Kurt. I might take a stab at it but really, I don't have a huge vise or the flange nut tool and also, have never rebuilt a gear box. I did talk to my local guy and showed him some close ups of the swarf which I think is a mixture of steel dust but also some small bits of bearing shell being peeled off. He agreed it looked like bearings and probably the gears and shafts are fine. Still about $1K to replace all the bearings. But that's Canuck bucks. You can add at least 35% if I send it to the USA rebuilders like Porter, Clement, Cutter and Anton. And then the shipping of a pretty heavy object.

Anyway, she's all back together as of last night. Took me two hours to get it out, half a day to go out of town to get 4 drive shaft bolts and then yesterday to clean, prepare and install my spare gear box. I did have the tank and battery left to put on this morning as I decided to repaint the battery tray. After traffic dies down a bit this evening I'll go for a spin and see how this gear box is!
Rebuilt by Bob Clement in Montana, installed in a late 80's or early 90's GS and went a few K before the bike was in a crash and written off. Been in my shed for years waiting for this moment actually so I have never used it yet! Hope she's a goodun!