How long has she got Doc?

[SteveD]

Will a mono 85> tranny fit an 81?

Yes. Even a 650 trannie will fit too. Any ribbed trannie from ??1980 on...??
The issue will be the year and the circlip. Ask hzbloke from Beechworth as he had that to sort when he did his g'box last year or thereabouts. He might even have the tools?
The BM Motorcycles guys suggest a trannie after 1981 for different cut gears that are easier or maybe cheaper to replace. Not sure of the details, but a trannie between 9/1981 and the first non circlip year. Not sure when the circlip was dropped either, but it seems that if one has a non circlip g'box then one of the things to do if it gets opened is to put one in.

[ME 109]

Thanks Steve, I was reading just the other day what year the circlip stopped......88?

I was asking on another thread what can be gleaned from the magnetic plug as to the condition of a tranny. I think I jinxed mesself. My interest in asking that question was in consideration of getting a tranny from Germany as a spare for when the inevitable happened. That's all the info he gives really, and a very basic bench test.

[SteveD]

The $OZ being so good against the Euro lately and his history of fair and accurate description, the limited test available is the only thing stopping me from getting one too! However, if I saw what you saw on the bolt, I think I'd pull the trigger.

[hzbloke]

G'day,

The bloke from Beechworth here. Yep, I rebuilt my gearbox 50,000km ago. And again 20,000km after that. I should have fitted the circlip (actually a snap ring) the first time. I've cobbled together the necessary tools if you want to borrow them. They may not be BMW Special Tools standard but they do the job.

Your photo of the drain plug looks strangely familiar.

Cheers
Ray

[ME 109]

Gidday Ray,

A few of the chaps here know of my penchant for bmw special tools.

That's a mighty kind offer from you to lend your tools.

I 'spose I need to do some ground work firstly as to what is commonly replaced besides obviously worn components. Things like that little spring that breaks, and also the thing that actuates the neutral switch which has broken? in my tranny.

Is there certain brand bearing that is best, or are SKF, Timkin, Toyo, Fag etc all the same?

I reckon there's another ride or two left in the tranny but I don't want to push it now, lest I end up with a real shit fight.
It just goes to show that what you don't know doesn't hurt you.......until yer find out.
I have been most impressed with the transmission's ability to stand up to the workload I've placed on it. The old bangers got about 260,000 K's on it now.

I drained the final drive today, just slime on the plug. Another amazing piece of equipment!

[SteveD]

...
It just goes to show that what you don't know doesn't hurt you.......until yer find out.
I have been most impressed with the transmission's ability to stand up to the workload I've placed on it. The old bangers got about 260,000 K's on it now.

I drained the final drive today, just slime on the plug. Another amazing piece of equipment!

Yep, the final drive..It can have issues too! Asymptomatic.

[ontic]

Hey Jeff,
If you decide to rebuild it yourself I've got a gearbox bearing kit from motobins I need to sell. Whatever the cheapest price you can get it for- I'll beat it!
I was going to try my G/S box myself but I've been convinced otherwise... I'm going to hand mine over to Paul Rooney to do, and he prefers to use his own bearings.
When looking at doing it myself I was going to follow the 'alternative' method of measuring axial shaft play (soft soldering wire or something similar).
http://jhau.maliwi.de/mot/gearbox.html
I'd like to try the gearbox rebuild myself one day but I want to get the G/S done sometime this decade and when it is done I don't want to be pulling things down again for a quite a while.
Cheers,

[Airbear]

Just read Jörgs page on the gearbox rebuild. Excellent tech writing - he makes it sound if not easy, at least doable, with care. Interesting prospect.

[ME 109]

Thanks for your offer Hans, certainly a lot of research is needed to be able to properly identify all 'worn' parts.
No point just replacing bearings only to find sooner rather than later that other components needed replacing.

I've just started looking for the ideal? site covering a 5 speed overhaul.
I'm sure there will be a well presented pictorial and text out there somewhere.

[ME 109]

Just read Jörgs page on the gearbox rebuild. Excellent tech writing - he makes it sound if not easy, at least doable, with care. Interesting prospect.

Prolly my only prospect Charlie, at the moment anyways. Where's Jo..rgs page? How do you get those eyes to stay up on top of the o? They keep falling off for me. o.. see