Good resource for basic bike repair?

[unflinching]

So I got a bike and I'm loving it, but I have trouble doing basic maintenance and repairs on it because I just have never had to before.

I have an internal gear shift (Shimano 8-Speed Nexus internal), which I've never had before, I've always only had bikes where there are multiple teeth and a derailuer. Right now I'm having a problem where I can only upshift, and if I try to downshift the shifter cable goes slack. If I get off the bike and physically push the contraption at the back it downshifts, so I'm sure something just needs a tweak somewhere.

Anyways, I'm googling but can't find anything, and I feel pretty confident it's an easy fix.

Is there some awesome secret n00b bike repair forum somewhere?

[Russ]

Shimano's website features very thorough technical documents (such as these) on all their products.
sheldonbrown.com is good for general advice and many of the more obscure things
parktool.com has a repair section that covers most modern components (maybe not IGH's though, not sure)
bikeforums has a mechanic's section. if you can't find the answer written down somewhere, someone there will know

sounds to me like there's a problem with lubrication, mechanical interference, or a return spring, but it's hard to tell from here ;-)

[Russ]

You think some WD40 might clear things up? :P

nonononononono. not sure if you were joking but WD-40 is srs bsns. No WD40 on bikes ever. a) it's not a lubricant and b) it'll fuck up any lubricant that's in there. Internally geared hubs with internal brakes are especially dependent on proper lubrication, because the gearing requires lots of oil while the brake requires high-temp grease, then all the seals and bearings require waterproof grease on top of that.

I did some more digging for you. Here's Sheldon's page on Nexus hubs with more links at the bottom of the page, a page with step-by-step photos of the disassembly and lubrication process, and another page that doesn't seem to have much point beside pointing out design flaws, but it has lots of pictures and might help you understand the inner workings.

If I were you and was sure that the problem was inside the hub, first thing I'd do would be take it apart and see if there was a simple mechanical fix. Then try lubricant baths to loosen everything up. Maybe ask your local bike shop if you can use their parts cleaner for five bucks or a six-pack first. If nothing works then, and you're sure the internal mechanism needs replaced, try and fix that before buying a new one. I mean, it's toast anyway, so why not give it a shot? From the tech docs it looks like the whole thing is held together by a couple E-clips which should come off and on pretty easily.

[ferrosapien]

There are two books that I have found to be pretty good. Bicycling Magazine's Complete Guide to Bicycle Maintenance and Repair, and Zin and the Art of Road Bike Maintenance

Both are fairly comprehensive, obviously the Zin title is focused on road bikes.  I have rebuilt a couple bikes from the ground up with the Bicycling Mag. title, and the text is great about identifying the necessary tools for every task.  A small investment and you can perform 95-99% of your own repairs, couple that with a good bicycle coop or a friendly used bike shop, and almost any repair can be done on the cheap.

[capital]

Oftentimes the problem with an internal hub is with the cable run or shifter as opposed to within the hub, so before tearing the hub apart, start by checking out the simple parts:
-inspect the cable run for any obvious kinks or catches
-disconnect the shifter cable from the mechanism on the hub, and push the arm/wheel/whatever and see if it returns on its own
-see if the cable moves through the housing smoothly when disconnected from the hub
-see if the shifter shifts up and down cleanly when disconnected

If the cable is catching in the housing (which would be my first guess from the problem description), a new housing and cable (stainless steel cable is definitely the extra cost for a bike you'll be using a lot in all weather) is a cheap and easy fix. Make sure that when the shop cuts down the housing, they either clean up any burrs/bent steel at the end of the housing, unless you have enough metalworking tools at home to handle it yourself.