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R1200 rear main seal tubes


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I'm replacing the transmission and clutch on a 2007 R12 GSA due to a bearing failure on the input shaft. When the bearing disintegrated it wallowed out the seal and, of course, ruined his clutch disc. I REALLY don't want to ruin the replacement clutch because I didn't take the time to replace a seal so I would like to preventatively replace all seals that could contaminate the clutch. The transmission input shaft and motor harmonic balancer should be relatively easy.


However, the crankshaft seal looks to be much more involved. Per my RepRom, there are three special tools required to perform the job:

A. The crank locking tool

B. The "TDC locking pin" (clutch housing pin)

C. The seal driver


The crank locker will have to be purchased. I feel like I can fabricate the TDC pin because it has such a simple design and function but not sure. And the seal driver is much more complex than the traditional seal driver due to the diameter and height of the crank.


So my questions are...


1. Would anyone be willing to rent any or all of the specialty tools to perform this job? I could do the job in a day and have them back in the mail the next because the bike is already disassembled. I could also put a deposit on the tool(s) for your protection.


2. Has anyone had success in fabricating any of these tools? I do not have a lathe or CNC machine in my garage. I am talking about shade-tree fabrication here.


Also feel free to comment on my need (or lack thereof) to replace this seal. Of all the seals, I suspect this one needs replacement the most since the input shaft would have wobbled wildly once the bearing was no longer keeping it located on axis. Even though the clutch offers a lot of isolation between the two shafts I still think it could have transferred enough energy to damage the sensitive seal.

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Afternoon James


I have only done one rear main seal on the 1200 hexhead, for that I used a piece of Mylar to slide the seal over the crankshaft. For the seal driver I borrowed one from my BMW Tec friend.


You could make your own seal driver using a piece of PVC pipe of slightly larger diameter than the seal OD (if you can find something)



I made my own 1150 seal driver from PVC pipe on my lathe. Lacking a lathe you actually could fabricate one with a hand grinder & a file. All you need is the proper depth step so the seal seats at the correct depth.


The IMPORTANT thing is to make the driver BEFORE removing the original seal so you can make sure the homemade driver will seat the seal at the correct depth. The driver doesn't have to be pretty it just has to work & seat the seal at the correct depth.


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Thanks DR. I have seen others use PVC tubing as a seal driver which very well may work in this instance. I'll take a trip to the hardware store with the calipers and see if the right size tubing exists.

I realized that I really don't need the engine locking device after more careful review of the procedures. And I'm pretty sure I can come up with something to act as a TDC Locating Pin. However, I'm still concerned I may have trouble using PVC as a seal driver in this application but we shall see...


Here are pics of the factory tools in case anyone is curious:


Engine locking tool:



TDC locating pin:



Seal driver:


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