1200 GSA transmission whine

I need to do this on mine, got slight play thats not going to improve.
 
I need to do this on mine, got slight play thats not going to improve.

Its not "that" bad a job. But so unnecessary for the sake of another bearing and less of a deep dish on the rear wheel hub.

Get the drive flange to 150C - I used a blow lamp as the 2Kw hot air gun wasn't getting the job done. The hot flange just slides off with a pair of welding gloves to wiggle it free. You can get a cheap IR thermometer to take the temperature readings. Mine came from Lidl for £20.

The cover plate unbolts and out comes the crown wheel and shaft assembly. I made a wooden stand to support the cover plate and knock out the shaft. There's no convenient way to heat the bearing race and chilling the shaft with an ice pack would chill them both. You need a press or a big hammer and protection plate for the shaft end.

You now have a bare crownwheel with the bearing still in the side cover. You need some uber circlip pliers to get the bearing circlip out. Then heat the cover to 150C and the bearing virtually drops out.

Assembly is easy if you heat the outer parts and chill the inners. I had the cover plate to 150C and the bearing direct from the freezer. The bearing simply dropped into the case cover. Ditto with the chilled shaft which slipped easily into the bearing.
 
Thanks for the info. Is the bearing commercially available, or BMW only?

Got a 60 ton press at work, circlip pliers, induction heaters etc and done the drive flange before so I will probably do the job once I can gather parts, I may even make a fixture and replace the input shaft bearing and seal whilst at it (already got the castle nut tool)
 
6013 2rs c1 on an earlier non breather fd
Later breather type is totally different.
Don’t try and drive the crown wheel out with a hammer ,you run the risk of damaging the end and compressing the circlip groove,
Use the press:rob
The housing needs to be properly supported though as they can crack .
Bendy was lucky to get the wheel hub off,I regularly see 10 tonnes on my press before they have moved,and that IS heated to 150
 
Thanks Mike,
At present the play is only slight and getting no worse ( in the last 2000 miles anyway ), I am in no panic to strip and repair. I shall pop to BRT Bearings and get some quotes and take it from there. If and when it gets quiet in the dockyard I'll get it sorted at my leisure.
 
I wondered about going to an SKF bearing but costs were much the same as the OEM FAG bearing.
My concern was clearances within the bearing which will be critical. Who knows what they are on the OEM so best to get the correct part.

I made a thick plywood support for the back plate as there’s not much material to support.
 
If its a 6013 sized race, double sealed with a C1 class fit as Mike specified, it should be manufactured correctly regardless of brand ownership.

We are talking about microns of grind.
 
If its a 6013 sized race, double sealed with a C1 class fit as Mike specified, it should be manufactured correctly regardless of brand ownership.

We are talking about microns of grind.

That’s the information I didn’t have. So stuck with OEM brand bearing. Elsewhere on the bike people have preferred to use SKF - where that’s possible. Maybe it’s some sort of brand chauvinism but I’ve always had a preference or SKF.

The difference between class fits is indeed minute but hugely important with a design that uses one ball bearing for all of the lateral stability.

I heated the housing and chilled the gear spindle (put in plastic bag) and chuck in the freezer for an hour). The parts dropped together.

I didn’t do this but suspect a couple of freezer gel packs packed down the spindle tube while the drive flange is still (very) hot would improve its ease of movement. 150C outside and well below zero on the inside has to help.
 
I heated the housing and chilled the gear spindle (put in plastic bag) and chuck in the freezer for an hour). The parts dropped together.

This concerns me,
You fitted the bearing into the housing,then the circlip,then the oil seal?
Even with housing,bearing and seal heated and the crown wheel chilled it should have been a bit tight,
I’ve Seen crownwheels that have had the main bearing spin on them and have been a loose fit like that.
Added to this heating the new bearing and seal to a high temp is not a good idea.
The crownwheel and housing assembly should also be rotated as they are pressed together to ensure the oil seal isn’t flipped inside out.
Hopefully all is well but it would be worth keeping a close eye on things for a bit

Edit also just reread your previous post,it sounds to me like it came apart too easily!
Keep a close check on play in the wheel,
It doesn’t read like it is a good tight interference fit into the bearing and hub
 
The parts went back ok with suitable heat or chilling of parts.
New main seal added after housing had cooled.
Chilled to -18C the crown wheel shaft into wheel bearing was a firm fit. I made no attempt to heat the bearing assembly. Don’t want to stuff the oil & grease seals.
Not yet refitted the drive flange. If that’s loose I may have wasted the cost of oil seals and bearing.
 


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