seahabit said:
I haven't see any threads on the initial FD oil service, after a rebuild. Upon draining the FD oil at 1,000 mi after the crown and tapered roller bearings were replaced, I found it contained more glitter, and the magnet had more fuzz than I'd ever seen before.
Can someone please put the "This thread is useless without pics" on this?
At 2.000 mi there was a some sludge on the magnet and the oil was dark, but it lacked the look of glitter. At 3,500 miles, oil had a mildly darker coloration and only a slight coating of sludge on the magnet.
I've done the "rear wheel play test" and spun the wheel while dry (not me, the bearing) after flushing with solvent while listening for problems. Nothing to note. I'm aware these tests aren't definitive, but I couldn't stop myself.
I'm not looking for the prediction of impending doom for my final drive, just wondering what others have found on their first oil changes.
Is that my rebuild? I have spreadsheet data for a FD rebuild for you. The spreadsheet data shows preload shim calculations and my findings regarding existing shim thickness. It doesn't have data regarding changes to other components like the tapered roller bearing.
I've gone through my message archives and don't see the correspondence but I have to delete msgs periodically because the mailbox gets too full.
Did I post pics for your rebuild after I did it? If it is my rebuild, I want to reconstruct what I found during the rebuild. Specifically I want to know why I replaced the tapered roller bearing, if I did. You state tapered roller bearing(S), are you talking about the swingarm pivot bearings which are needle bearings or are you talking about the tapered roller bearing that is inside the FD?
Please confirm if this is my rebuild.
Grey fuzz is normal during wear-in following a rebuild. Shiney metal flakes should not be being generated. If a crownwheel bearing failed, depending on how far the bike was ridden with a failiing bearing, metal flakes can get up into the input pinion shaft area. (this is another reason why continuing to ride after symptoms of bearing failure is discouraged). I always try to flush out the pinion shaft area during a rebuild. It is relatively inaccessable and while unusual, it is possible that metal flakes can hide in there in spite of efforts to flush them out in the parts washer. In short, it is possible that metal flakes can find there way out after a rebuild and not be a symptom of new failure.
If the shiney flakes are residual from the previous failure, they will eventually all be captured by the drain plug magnet.
Really dark lube can be a sign of aluminum wear. There are two failures that generate aluminum suspension in the lube but the crown wheel bearing doesn't generally generate much aluminum. Aluminum will not be captured by the drainplug magnet like the gray fuzz and shiney flakes will.
I recommend changing the lube (use cheap lube, I like WalMart Tech brand) after a few hundred, up to a thousand miles, again. Contrary to the suggestion above, if you are seeing shiney metal flakes, I'd recommend frequent checks of the drainplug. It is possible to check without draining all the lube. Pull the drain, hold the lube in with a finger while you inspect the plug. (a second pair of hands might help). If you loose much lube in the process, you can just top it off. If you are still seeing increasing metal, and it is my rebuild, ship it back to me (once I open the drive I can tell if it is my rebuild).
"I've done the "rear wheel play test" and spun the wheel while dry (not me, the bearing) after flushing with solvent while listening for problems. Nothing to note. I'm aware these tests aren't definitive, but I couldn't stop myself. "
The "shake the wheel test" is definitive, it will definitely tell you nothing. By all accounts, by the time you can feel wheel movement, there will be lube leak at the hub seal.
Rotating the wheel and feeling for roughness is equally difficult. Only advanced bearing degradation will be detected, and by that time you might also be feeling it during the ride on smooth road surfaces.