crown bearing in fd

[steveg]

my fd has some play in the crown bearing, am thinking about replacing it before the fd is totally wiped out. has anyone done this ? and what were the results this is the second fd on the bike and i really dont want to go for another 800 bucks

thanks steve

[twilmotte]

How many miles did you get on the first FD? And on the second one?

[steveg]

90,000 on the original and the 2nd one was used with 6,000 on it now have additional 64,000

[Dances_With_Wiener_Dogs]

If it looks like this, then I'd suggest replacement:

 

 

This is when the primary bearing (primary? errr, the one holding to the rear wheel?) started to go so I stripped it at 75,000 miles.

[JohnBeaven]

When I has the bearings replaced in my R1100RT at about 100000km the bearings looked okay. However, on the bike there was a definite rumbling from the final drive.

 

They certianly looked nothing like the one in your photograph.

[chrisz]

I've just replaced my crown bearing after finding metal slivers in the FD fluid. The fluid was also very dark in colour. Did the work myself without removing the FD. Just take off the rear wheel and get the bearing from there. I posted questions on this forum a week or so ago, and received much appreciated infomation, including step by step instructions. About $200 in parts and 8 hours of my labour. Replacing the bearing did cure the rumbling vibration I had. (My R1150RT has ~95K km)

 

Good luck.

[steveg]

thanks for your help guys , disassembled the fd on the bike , inspected the bearings, everything looked fine. turns out that the play was in the paralever bearings and not the fd,loosened and retorqued the bearings . no more play in the driveline

steve

[Steve W.]

thanks for your help guys , disassembled the fd on the bike , inspected the bearings, everything looked fine. turns out that the play was in the paralever bearings and not the fd,loosened and retorqued the bearings . no more play in the driveline

steve

I had the same problem (looseness) on a 96 RS. I pulled the rear drive and the little bearings fell apart. You may consider checking these bearings. It is a common problem. YMMV.

Cheers

Steve (01 GS)

[OoPEZoO]

thanks for your help guys , disassembled the fd on the bike , inspected the bearings, everything looked fine. turns out that the play was in the paralever bearings and not the fd,loosened and retorqued the bearings . no more play in the driveline

steve

 

Nice . That always makes you feel good.

[steveg]

yes I know, I've had this apart many times with repairing original fd, then replacing fd with a used one then to rebuild the trans. Im one my third set of pivot bearings. just ordered the bronze oilite bushings from rubberchicken for the next episode. I love this bike but it has its weak points. fd and pivot bearings are at the top of the list . all in all the bike has been pretty reliable considering I've put almost 160,000 miles on it and not all of them have beem easy ones . thats all I have to say about that.

steve

[OoPEZoO]

yes I know, I've had this apart many times with repairing original fd, then replacing fd with a used one then to rebuild the trans. Im one my third set of pivot bearings. just ordered the bronze oilite bushings from rubberchicken for the next episode. I love this bike but it has its weak points. fd and pivot bearings are at the top of the list . all in all the bike has been pretty reliable considering I've put almost 160,000 miles on it and not all of them have beem easy ones . thats all I have to say about that.

steve

 

Hate to hijack here, but I have to ask

 

Have you had to open the engine to repair anything in the 160k miles? Also, what happened to your transmission and what mileage did it go out on you?

 

I currently have about 85k miles on my bike, and I've been fighting with the idea of keeping it until it pops, or looking for a low mileage replacement.

 

I've already had my hall effect sensor and final drive fail so those should be good for a few more miles. While in there, I also replaced my pivot bearings with the ones from rubber chicken. My only real deciding factor has been coming down to "how long will my engine and transmission last". I feel pretty comfortable with the engine, but the tranny always leaves me with a question mark.

[RFW]

You cannot just replace the bearing.

 

It is manditory to measure preload tolerence and replace the bearings shim with one of correct thickenss for the NEW bearing. The reason for this is that the axial tolerance of these bearings, is GREATER than the very tightly controlled preload dimension.

 

To be specific, the preload must be between 0.05mm and 0.10mm . But the actual axial tolerance on the bearing is in the range of +/-0.2mm . This means that if you do not measure and reshim as required, you could end up with excessive preload (thus leading to early failure of both the new ball bearing AND the tapered roller), or you can end up with no preload at all and actual play in the system (resulting in bearing AND gear damage).

 

It is also important NOT to replace the tapered roller bearing if at all possible. If it is in good shape, leave it alone. The reason for this is that replacing this bearing likely also requires replacing its shim (bearing tolerance issues again). But this bearing's shim controls the gear tooth contact engagement. If this is wrong, you destroy your gears in short order!

[steveg]

the trans had a shim wear out which caused the bearing to be ground into the gear with the u shaped part on it i think towards the front of the trans.the symtoms of that were increasingly loud sound when in nuetral with the clutch engaged. that was at 120,000 miles. had trans rebuilt and by a shop and I r&r it myself. the exhaust valve burned out at 140,000 miles , I had the heads rebuilt at a shop and I r&r my self and also replaced the piston rings and the cam chain guides on the rt because they were broken, I still have the original hall sensor. you should be good to go for alot more miles

 

 

 

 

RFW

I did not replace any bearings in the fd just inspected them and they looked fine but I know what you mean because the first time I had play in that bearing a shop just shimmed it with a thicker shim and the fd totally self destructed within 2000 miles and had to tow the bike back to the shop and replace the fd with a used one do to so much damage to all the gears and bearings.the parts would have cost more than a whole new fd

steve

[smiller]

the trans had a shim wear out which caused the bearing to be ground into the gear with the u shaped part on it i think towards the front of the trans.the symtoms of that were increasingly loud sound when in nuetral with the clutch engaged. that was at 120,000 miles.

That particular problem is not caused by a shim wearing out, but it is something to watch out for and you're certainly not alone in seeing it. I would strongly suggest that anyone with a high-miles 1100 send a transmission oil sample off to Blackstone every once in a while to as to detect this or any other problems early.

[steveg]

In my case I found part of what looked like a shim on the magnet when I drained the trans and then the noise kept gettig louder

[OoPEZoO]

the trans had a shim wear out which caused the bearing to be ground into the gear with the u shaped part on it i think towards the front of the trans.the symtoms of that were increasingly loud sound when in nuetral with the clutch engaged. that was at 120,000 miles. had trans rebuilt and by a shop and I r&r it myself. the exhaust valve burned out at 140,000 miles , I had the heads rebuilt at a shop and I r&r my self and also replaced the piston rings and the cam chain guides on the rt because they were broken, I still have the original hall sensor. you should be good to go for alot more miles

 

Thanks for the reply.......I figure my bike only needs to last 3 more years and another 40k miles and I will be OK. If I can get that without a major mechanical engine or tranny failure, I will be thrilled. That will leave me enough time to get Danielle through nursing school, then maybe I can justify replacing it with something else. Of course, if it lasts that long....I will most likely end up adding a bike instead of replacing a bike