JohnBrooking

I have a Giant hybrid with an 8-speed internal hub, which I thought would be great for low-maintenance winter commuting. However, occasionally, moisture gets into either the cable or mechanism outside the hub and it freezes up on cold days. The cable terminates at a little plastic sliding device outside the hub, and I suspect it's somewhere in there. It could be in the cable, but that's totally enclosed from the shifter all the way to where it attaches to the hub assembly, so I'm not sure how moisture would have gotten in there, except maybe if some got in the shifter and rolled down the cable.

Anyone else experience this, and found a good way to eliminate the moisture? I'm thinking it's probably the mechanism, and will probably requiring removing the rear wheel, disattaching the cable, and taking apart, drying out, and re-lubing the mechanism outside the hub with some kind of dry cold-weather lube. Maybe also removing, drying, and reinserting the cable. But I don't feel confident in this much disassembly (I unattached the cable once and couldn't get the mechanism back together real well), so I may have to take it into the shop over the weekend.

This morning I took a hair dryer to the cable (after leaving the bike inside all night), and WD-40'd the outside hub mechanism and the cable where it goes into the housing, but it still froze up!

Any advice?

jbarham

Since WD-40 is a detergent and not a lubricant, you might be able to help yourself out if you apply either grease or a heavy oil like phil's tenacious.

CastIron

B.S.

There's a wet weather kit for the nexus 8 sp hub to prevent it. Contact Shimano.

rodar y rodar

The OP`s use is exactly what WD 40 was designed for- water displacement.

I read something about that wet weather boot for Nexus, but never managed to find any pictures or anybody selling them. Are you sure they really exist and not some idea that never went into production? I don`t have a Nexus any more, but I`m still wondering what the deal is with that boot.

JohnBrooking

I'm guessing this is the wet weather kit being referred to?

Alfine/Nexus Inter-8 Hub Wet Weather Cassette Joint



Average retail price on the pages I found was $12. I shall be asking to my bike shop about this, probably when I take the bike in to them this weekend. Thanks for the advice, everyone!

JohnBrooking

FYI, when I took it in today, the mechanic looked it over and decided that the problem was in fact moisture in the cable. This was based on the fact that the cable could still move both at the shifter and the hub. (I hadn't tried the latter test very thoroughly.) Plus I do notice it happening pretty much at the water freezing point.

The gear cable on this bike (Giant Cypress EX) is routed under the bottom bracket, then back up to the hub, so the bottom bracket is the low point. And it's totally enclosed, so the theory is that water has collected in the cable housing under the bottom bracket and has no way to get out. He re-routed the cable so there's no point lower than the hub, and recommended WD-40 at both ends of the cable and storing it inside with the front wheel elevated, so the lube runs down to the hub and takes the moisture out with it. We'll see if that does the trick.

He could have taken the cable out and rerun it, but since I was talking about getting the wet weather cassette joint, which would also involve a new cable, he presumed I didn't want to go to the trouble and expense of that twice. Charged me a grand total of $5 for the re-routing and advice.

rodar y rodar

Good- glad you (hopefully) found the problem. Did you locate the new cassette joint and boot? Why would that require a new cable?