slcbob

Hi there. So I mangled my Nexus SC-8R25 hub. See pics. At a minimum, from this diagram, I know the bearing clip #7 is bent and so are the two retaining spring/clips that go around the driver unit #11 to hold in the pawls. A few pawls were out of place but I've got them all and they look OK. The retaining springs I'm talking about are the not-quite-circular things in the pic just above the axle assembly by the loose bearings and pawls.

I'm looking for other damage, haven't completely disassembled it but don't immediately see any. I'm confused that the end of the hub shell slide spring #26 pokes up from the groove in the shell where it rides. You can see that in the pic of the shell - is that normal? I don't remember seeing that when I took the hub apart a while ago to know if it is right or wrong, and am not even sure that's where that "spring" goes. I'm not sure what the tolerances should feel like so can't tell if the wiggle in the driver unit is normal or not.

I've asked around a bit here but haven't found an IGH savvy LBS mechanic. If you know of one in the DC area, please point me to them.

I figure my options are:

1. Ship it off to a specialist such as ABR for an overhaul. It looks like that would run at least $100 + parts + round trip shipping, so ~$150 or more.

2. Buy a new and better hub and lace it into my current wheel (I can do that myself). An SG-8R36 is only $175. The 8 speed Alfine is only a little more so I'd consider upgrading even further but I'd check for reusability of shifters, hub flange dimensions, etc.

3. Replace the parts I know are bad, slap it all back together, pray and test drive. I'm not confident in my ability to diagnose/inspect, but if it is good enough or bad enough, I'll find out by braille. if I can find the pawl retaining springs cheap and separately from the driver unit (which is $50-$70), the #7 bearing clip is only a few bucks. I see a few websites in England selling #7, may try ABR to see if they'll sell parts, but welcome supplier recommendations.

What do you think?

As for what went wrong, I'm not sure. The hub was old and had a lot of miles in it, so I overhauled it about 700 miles ago. Reassembled after ATF soak and using the special Shimano cake icing grease. I could have gooned something up inside when I cleaned and lubed it, probably didn't right then but might have reassembled it a little loose. It ran well and saw me through a few local rides plus all 450+ miles of RAGBRAI without incident. I was out on a ride recently, things felt a little funny on the rear end, and I found that the lug nuts were loose. About 5 miles after tightening them I started getting more grinds and chunks in the mechanism in 5th or 6th gear. I shifted around a bit, things were best in 4th, so I rode back to civilization (another ~10 miles) there and now here I am. When I opened the hub up, the bearing clip was obviously bent, four of the balls had come out of the clip and were in there messing with the pawls and such. Best guess -- when the lug nuts loosened up too there was some torque or bending, +/- a little slop from my overhaul, that allowed things to get out of whack enough to mangle itself over the next few miles.

mconlonx

I would get a new hub and re-lace the wheel. Set aside the old hub and use it for parts. I think this would be fastest and would give me the most peace of mind.

slcbob

Any other thoughts on this?

I'm heading up to Boston and may see if Harris Cyclery or another spot up there can give it a look. So DC or Boston recommendations welcome.

fietsbob

Aaron in Seattle suggests regularly servicing them if used in Foul wet weather .. fresh clean re-grease.

If hubshell is OK, maybe buy another of same hub and swap in the new Core , bypassing the wheelbuilding.

slcbob

That's a good idea, fietsbob. Unfortunately, it looks like the newer models have upgraded guts and the shells aren't compatible. In a quick search, I haven't found any new old stock of the older hubs at all, let alone at a discount that makes them attractive relative to the newer model even with the relacing hassle.

fietsbob

Same spoke hole circle diameter and number of holes is a measurable piece of Data.. to re use your spokes and rim..

But there are also ready built wheels even back room wheel building divisions of like QBP .

the parts to make up the wheel are distributor costed, so less than if your LBS gets the parts and does the work