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Hi
When should I change the oil on my 1200S final drive?It's got 19000kms now.
Thanks

The 'maintenance free' drive is now recommended for service at 600 miles then at every 6000 mile service.

If yours has not been done yet then if definitely needs doing.

The latest service instruction decreases the amount of oil. If you need a copy of it PM me your email and I will send you a PDF.

It's an easy job to do. The only awkward bit is getting the fresh oil back in. I use a large syringe I got from the vet which means I can accurately measure the amount I put in.

Herb wrote:I use a large syringe I got from the vet which means I can accurately measure the amount I put in.

That is the way to do it. Do not mix the oil grades. The syringe I use for gearbox oil is only used for that type of oil.

The amount to fill in is 180 ccm. Sure don't mix the oil grades ... I use use the same oil for the FD and gearbox (Castrol Syntrax 75W90 or Motul Gear 300LS 75W90 - needs to have the spec API-GL5 for the FD).

Brgds
Oliver

Yes, same oil for both. The syringe and tube lives in a ziplock bag to stop contamination.

tanneman wrote:Yes, same oil for both. The syringe and tube lives in a ziplock bag to stop contamination.

I do the same so it does not get mixed up with my heroin syringe.

You get injected with oil you'll end up a oilhead

Herb wrote:The 'maintenance free' drive is now recommended for service at 600 miles then at every 6000 mile service.

Why am I laughing? I shouldn't be laughing! lol

Harry Lime wrote:

Herb wrote:The 'maintenance free' drive is now recommended for service at 600 miles then at every 6000 mile service.

Why am I laughing? I shouldn't be laughing! lol

Is it accompanied by a Herbert Lom twitch?

Try adding 200-210mm rather than 180.

180 just isn't enough oil.

Herb wrote:
The latest service instruction decreases the amount of oil.

Seems strange, I'm inclined to agree with Steptoe, I always feel happier putting a "little more" oil in anything rather than a "little less" , however, I know too much can pop seals etc so best to follow recommendations.

Wonder why the service recommendations are changed ?

The amount of oil in the FD has been revised by BMW from 220 to 180 ccm. And that for good reason.

The FD originally did not have any degassing/vent (later the FD was modified) and the oil filling of 220 ccm resulted in foam building up in the FD. As a result the front AX bearing did not get enough lube and heated up beyond specs. As a further result the plastic cage breaks and dissolves. And then the bearing fails.

The FD was later modified (new version has a drain plug on the bottom and and a vent). But for the previous FD the amount of oil was reduced in order to reduce foam building up in the FD ...

If you have the "old" FD and if you want to reduce the possibility of damage I can only suggest to stick to the official amount of 180 ccm.

A good howto can be found here http://www.r1200gs.info/howto/reardrive.html

Brgds
Oliver

Steptoe wrote:Try adding 200-210mm rather than 180.

180 just isn't enough oil.

NO NO NO - DO NOT OVER FILL - There is no breather on these final dive units and when teh oil gets hot it expands. The Stealer (non BMW) who serviced my bike before I bought it overfilled it and it blew the large bearing seal. Itss till weeeping now - I must get round to chaging it this winter. It's been leaking the last 10,000 miles, The reason we say 180 is beacuse the capacity is 200 and you just cannot drain it all out unless you leve it for a couple of days. 180 is certainly enough oil, four teaspoons full too little won't cause it to wear out but four teaspoons full two much can blow the seal.

As well as the oil expanding due to heat, the air in there will also reach a similar temperature. Air also expands with heat. A compound effect.

Gearbox oil also expands due to churning. Although, in an enclosed casing with no vent, that raises an interesting question. If churning is essentially aeration, then surely it can only be mixing in air that is "trapped" in there with it? So I'm not convinced that churning itself will cause any increase in air pressure. In a "conventional" set up, with breather plug, the churning causes a rise in oil level, but surely only by taking air on board.

The heat produced definitely will expand the oil and the air though.

Glad to hear they've seen sense and gone back to a breather plug (according to omg1010).

Yes, second generation FD has a breather plug and can easily be identified by the drain screw on the bottom of the FD.

Anyway, I strongly suggest to go for the recommendation of filling only 180ccm.

Brgds
Oliver