How to tell leaky seal or final drive repair?

[KDeline]

How do I know if this is a seal problem or if the final drive is going out? I can barely feel a slight play at the 12 and 6. But it’s so slight I question if there is any.

[dirtrider]

8 minutes ago, KDeline said:

How do I know if this is a seal problem or if the final drive is going out? I can barely feel a slight play at the 12 and 6. But it’s so slight I question if there is any.

 

Evening KDeline

 

That looks like the seal is leaking. It could be the seal itself or it's possible the final drive was over-filled. 

 

The final drive oil fill amount was lowered because of some oil leakage issues. 

 

On a cold final drive a little  12 and 6 movement is normal & most have that. The actual BMW spec is up to 1mm (cold drive). 

[KDeline]

Final drive has not been filled for thousands of miles, this just started. Compared to three bikes, that one and one other have barely perceptible play at about seven and one. The other one, I can’t detect any play. So yours and my assumption is that it’s a bad seal. I just don’t want to be riding it and it go out on me.

[dirtrider]

5 minutes ago, KDeline said:

Final drive has not been filled for thousands of miles, this just started. Compared to three bikes, that one and one other have barely perceptible play at about seven and one. The other one, I can’t detect any play. So yours and my assumption is that it’s a bad seal. I just don’t want to be riding it and it go out on me.

Evening KDeline

 

I definitely can't tell if your drive is going out over the internet, but typically a leak from that seal is just a seal leak. If it starts leaking on the other (crown bearing) side then that can spell trouble in your future. 

 

Pop the little black plastic seal cover off so you can get a better look at the entire seal (it needs to come off to replace the seal anyway).

 

Can you feel any growly type roughness in your front foot pegs (through your feet) as you coast slowly with the engine noise turned off? When the crown bearing starts to go you can usually feel it in the footpegs when it gets bad enough.   

[KDeline]

So do I pop the rear wheel off and look at it, or would already be showing with the wheel attached?

[Lowndes]

KDeline,

 

As Crocodile Dundee says, "Why, that's not a knife, THIS is a knife!!"

 

 

Just add some oil when you stop for lunch and drive it like you hate it.  Then fix it next winter.

[KDeline]

So I assume you have the full blown final drive failure?

[dirtrider]

3 minutes ago, KDeline said:

So I assume you have the full blown final drive failure?

Evening KDeline

 

That is an entirely different final drive type with a very unique failure. Your 1200RT can't fail in that way as your 1200RT has a hollow spool axle. 

[dirtrider]

5 minutes ago, KDeline said:

So I assume you have the full blown final drive failure?

Evening KDeline

 

You shouldn't need to as the leak on that side (if you ever get one) will show up between the wheel & the drive side cover (it will be evident) 

[KDeline]

OK, so I assume this is good.

[KDeline]

[dirtrider]

5 minutes ago, KDeline said:

OK, so I assume this is good.

 

Evening KDeline

 

Yep, the rotor side looks nice & dry. The R/H side looks like the seal has been leaking. 

 

 

[KDeline]

Thanks, I’ll see if I can get this thing replaced on my own. I have the seals so here we go.

[Lowndes]

16 minutes ago, KDeline said:

So I assume you have the full blown final drive failure?

Yep.    But Dirtrider got me thru it.  Just do what he says and it will be good.

 

I was just sayin it could be worse!!

[dirtrider]

18 minutes ago, KDeline said:

Thanks, I’ll see if I can get this thing replaced on my own. I have the seals so here we go.

Evening KDeline

 

Just don't forget to remove the seal retaining ring first.

 

Then be very/very/very careful to not to drill too deep into the seal metal as it is so easy to damage the drive if you drill too deep. (use a drill bit stop, or a few wraps of masking tape to limit drill depth)

 

Once you drill 3 small holes & screw in the sheet metal screws you can use a piece of wood or other padding (protection) & a claw hammer (or side cutters over a fulcrum) to remove the seal. Try to not bend or damage the old seal as you can flip the old one over then use that to drive the new seal in.  

 

[Bernie]

It's very easy.You won't even loose any oil. I have done it on 3 different RT's. 

Just take your time.

[KDeline]

All finished, did most of what you said DR, marked the drill bit, but I did not know about the retention ring, until after a couple tries. Once that was out, the seal came out, fairly easy, cleaned everything up install the new one, use the old seal as a driver. I did put a little dent in the dust cap, so I guess I’m going to have to get another one of those. Now it’s time for a test ride.

[dduelin]

Sounds like you got it fixed by now. I had a similar seal side weep show up about 7,000 miles ago. I cleaned the seal out with a plastic Seal Mate tool and no reoccurrence to date.

[KDeline]

1 hour ago, dduelin said:

Sounds like you got it fixed by now. I had a similar seal side weep show up about 7,000 miles ago. I cleaned the seal out with a plastic Seal Mate tool and no reoccurrence to date.

Yeah, I wish I would’ve thought of that before I replaced it. How hard was it to get in between the seal surfaces?

[dduelin]

On 4/3/2023 at 5:16 PM, KDeline said:

Yeah, I wish I would’ve thought of that before I replaced it. How hard was it to get in between the seal surfaces?

Not hard at all as the FD seal is easily accessed all 360 degrees. When I bought this bike 48,000 miles ago the right telelever slider was seeping fork fluid and the Seal Mate cleaned out/ stop leaked that seal to date as well but doing fork seals is somewhat harder as access isn’t as easy.

[KDeline]

10 hours ago, dduelin said:

Not hard at all as the FD seal is easily accessed all 360 degrees. When I bought this bike 48,000 miles ago the right telelever slider was seeping fork fluid and the Seal Mate cleaned out/ stop leaked that seal to date as well but doing fork seals is somewhat harder as access isn’t as easy.

I have discovered that if I pull the fork off and clean, it usually stops the leak. That has worked every time so far, I think I have done five. Might have to try the seal mate.