Removing the gearbox

[georgesgiralt]

Hi !
Last Sunday, I took the bike out to add mileage on the odometer in order to reach the 1000 km limit after piston rings change. This, when reached will mark the end of the run-in ... And I would be VeRy HaPpY !
At about 20 km from home, there is a village. So I reduced speed and changed gears to prepare to stop the bike. Alas, the gearbox seized in 3rd as the infamous spring broke... I was lucky, the gearbox's spring did not broke in neutral !
I had to return home slipping the clutch (changed with the piston rings .... ).
So I study the dismantling of the gearbox, while waiting for the special tool to remove the output flange and the various parts I ordered from my dealer.
I had a look at the factory repair manual for the R65. Up to 1981, they advised to remove the gearbox after removing the swing arm. Then they advised to remove the engine bolts and slip the engine to the front, as much as it will go and remove the gearbox (the engine has to be supported on something not to mar the push rod tubes).
Last time I removed the swing arm and it was time consuming to re-assemble it and adjust the play. So the idea of having the swing arm in place is appealing.
What do you think, did someone has ever used this method ? Pro ? Cons ?
Thanks in advance !

[Bob_Roller]

With the swingarm bolted in place, I don't think the gearbox will come out, not enough clearance .

I've always removed the swing arm to remove the gearbox, only about 20-30 minutes work to remove it from the bike .

[donbmw]

Gear box will not come out with swing arm I place or even pulled back with shocks attached.

Don

[Lucky_Lou]

I did the splines on my 79 without taking the swing arm off, i did however remove the engine mounting bolts and with a trolley jack under the engine moved it as far forward as it would go. Dont forget to disconnect the battery first and if needed take the generator cover off as that will give you another 3cm..... ok just over 1"for our Imperial members. That said i bet there is not much differance time wise taking the swing arm off.
Lou

[georgesgiralt]

It's not the taking off that bothers me, it's the re-assembly and play adjusting which is time consuming.
I'll give it a try and report back... But it's freezing cold in the garage !

[Bob_Roller]

You can use my garage, it's 85 F (29 C)  in there at 1630 !!!!

[tvrla]

Of course the transmission will come out with the swingarm in place!

I've done it a number of time, the most recent a few months ago changing a clutch in a 74 R90. The R65 isn't any different. That's the way I do it these days - I used to pull the SA, but prefer this method.

The reason I prefer not removing the swingarm is the dirt that can enter the bearings - it's pretty messy in there, and it will need to be cleaned very well or grime will be forced into the bearings when the SA axle is replaced.

It's easy! Here's what you do:

Remove the mufflers.
Remove the battery box
Remove aircleaner and starter cover (starter cover might be able to stay)
Unbolt the UJoint
Remove all the other stuff that needs to come out, like pushrod & bearing, clutch arm, etc.

Ubolt the transmission

Remove rear engine bolt - the engine will practically balance on the front one.
 
Tilt the rear of the engine up and remove the transmission to the left side.

Once you've tried it this way, you'll be sold.

[livingdeadhead]

this is where ive been working on my bike rob!

[livingdeadhead]

so, is this a big problem with the r65? when i had a gpz 1100 (watercooled detuned zzr) the guy swore it was fine . should have test rode it! kept jumping out of fith gear , had to lift the motor out, strip the bottom off , gears cost £230.00 plus gaskets , the motor must weigh 250 lbs . a weak spot apparently.

[Lucky_Lou]

You can use my garage, it's 85 F (29 C)  in there at 1630 !!!!

-5c last night so i have moved my beer into the fridge to warm up, either that or loose a lip to frostbite.
Lou

[montmil]

If I was working on an Airhead gearbox...

There. On topic, as always.

On Saturday morning, Bengt Phorqs and I met for another casual, al fresco brekky at the Blue Hangar Cafe on board NorthWest Regional Airport. Then Phorqs had the audacity to score a free brats n' burgers lunch at Fort Worth BMW. Did he share this info with his riding buddy? N-o-o-o-o-o

Saturday, December 1, 2012 and I'm riding the R100S enjoying a sunny, breezy, warm 80[size=12][ch730][/size]F day here in North Texas. We don't get much of what most peeps call "winter".

[smiley=whistling.gif]

[georgesgiralt]

Hello guys !
So the gearbox is on a contraption devised to hold it on the wise during surgery... (An L shaped bar of steel I had rusting under the bench, with 2 holes to place two M8 bolts in the engine/gearbox assembly holes).
I used the method explained in the post 1982 BMW factory manual I saw at my dealer's.
Piece of cake. You do not have to remove the right hand carburettor, the mufflers (just unscrew the joint). So I think synchronising the carburettors back would be easier. I bet I would have to remove the mufflers to set the engine back on it's place.
I just have to wait for the special tools I ordered to show for dismantling and processing to the replacement of the offending spring... And I've to wait to next weekend to get the parts...
One question, though, is it possible to re-use the transmission bolts ? They have just been used for a couple weeks ! And less than 700 km !  

[Bob_Roller]

Are you referring to the 12 point 10mm bolt head fasteners ?

There are two thoughts, one is replace them every time you remove them, the factory manual states that they stretch and should not be reused .

Others, myself included, have reused them, so far no problems .

So, you'll have to make your own decision on this .

Just make sure you don't use lock-washers under the bolt head, this was an original configuration from the factory on some bikes, and you may still find them listed in the parts catalog .

[georgesgiralt]

Yes, these 12 face headed bolts. No, I did not had washer under them and did not put any.
So if I reuse them, what kind of Loctite product should I use ? (the original fitted by BMW was blue and solid, now it is white and some chips are missing. )  I guess that I've to wire brush them to remove all anti slip compound left...

[Bob_Roller]

I use blue Loctite .