rear hub snag

[mickwinf]

ok so i am rebuilding the rear hub on my 500 and have hit a snag. It is a refurbished hub with all new bearings and cush drive rubbers, the issue is when I try to replace the sprocket carrier assembly. If i use the d ring seal the carrier will not sit down enough even when i tighten the retainer ring down as tight as i can get it. If assembled without the seal everything looks fine. Is the seal too thick? is it necessary at all?
help please!

[Oddjob]

Which way round have you got the D ring fitted Mick? round side up or round side down?

[mickwinf]

Ken I am a bit confused about this, I have seen other posts, but if I am doing this correctly it fits around the bearing housing? The seal has the flat side on the inside diameter of the seal so both upper and lower edges of the outside diameter have a round edge, therefore either way up is the same? It seems to me an ordinary o ring would work just as well.

[McCabe-Thiele (Ted)]

Someone else here had this problem a couple of months ago iirc - was it the bearing not fully home?

[Oddjob]

There is some debate on the forum Mick on which side of the ring sits uppermost. The groove it sits in is flat, so you'd think the flat side of the ring goes against the flat side of the groove leaving the round side uppermost. However it an also be fitted with the round side down, this leaves the flat side uppermost and it makes some sense for that to be the way as it would mean it seals better (more contact area) and the reduced profile would also allow the sprocket carrier to slide on easier.

Which as you say makes you wonder why they fitted a flat sided or D shaped oring in there in the first place, if it sat round side up then surely a round oring would do the job as well, or is it flat so it doesn't twist out of shape as the carrier slides over it.

My head says it fits flat side up, which way have you got it ?

[K2-K6]

O-ring form into a square rebate should leave space for those two curved edges to spread into the groove corners, and allowing the flat outside face to move away from the other component.

It does seem logical to me Ken as you've stated it, curved in groove, flat out. Use plenty of silicone grease to slide it into place, said the customs officer to the Bishop 

Obviously, the flat side in the groove and it can't expand in there, leaving the outer now less compressible.

[Oddjob]

Got to say Nigel I didn't consider the compression the ring would be under and the ability for a round profile to deform into a square profile, yeah that makes perfect sense.

Try flat side up Mick and I would confer on using either silicon oil or silicon grease to ease it on.

[mickwinf]

even more confused as there is no groove, will take pics tomorrow

[Oddjob]

Groove is on the hub Mick, on the protrusion where the carrier fits.

[mickwinf]

OK I am officially an idiot! I did not see that the groove was in a raised rim so had the seal on the top! For future reference for other members I took a pic. Now as to the orientation of the seal, I think flat side into the groove, as the seal is about 3mm thick if it is turned inside out so to speak it would distort and be ineffective. If honda wanted flat side out surely they would have it manufactured that way? Now fitted round side out and still needs a firm squeeze to get it in. Now realised my spoke kit has the wrong size nipples so stuck again

[K2-K6]

 

At least you've got that bit sorted now.

[Oddjob]

Should have tried it both ways Mick so you can see if it made any difference. Might solve the debate once and for all.

[Trigger]

Removed and fitted hundreds of these O'rings, even off your old hub Mick , flat side down