DIY bike repair?

October 6, 2009 10:04 PM

I just bought a mountain bike on the cheap and want to make some changes, namely adjust the shifters (or perhaps change them altogether), and replace the handlebars. Is this a rookie-doable project or should I take it to a shop?

The bike has a full suspension, a lightweight frame, 18 speed, grip shift. I wish I had a pic to show you, but that's part of the problem--I can't find the brand Lejune anywhere on the interwebs. (It's possibly a Chinese knockoff of a different brand's design..or something). Anyway, the derailleur is Shimano, but the shifters are some weird no-name brand (Logan? Anyone heard of them?) There is considerable rust with the brake cables (which are otherwise in great shape), and the shifters (which ain't in such great shape; half the time there is a very delayed reaction when I change gears, and sometimes nothing happens at all.)

The other issue is that I think the frame might be a bit too small for me, but I think I can solve that by getting a different set of handlebars. I've already raised them the inch or so they can move up, but it's not quite comfy yet. The handlebars now are rather narrow and don't rise up at all--just a straight line. I want to get some that raise up a bit more, with U-shape bend in them. As of now I have to hunch over and my wrists get sore with the current setup.

I have some hex wrenches, a ratchet set, plyers, and a Leatherman. Your basic tool set. I'm pretty comfortable with the idea of taking my bike apart, but I wonder if I'll get in over my head before I know it.

Would it be a gargantuan task to 1) adjust--or replace--the shifters, and 2) replace the handlebars?

posted by zardoz to sports, hobbies, & recreation (14 comments total)

Yeah it's doable. Get yourself a copy of this (which is likely to be in one of its editions in good secondhand bookshops) and you're on your way.

Beware though, if you got your bike that cheap, a new set of shifters, cables, and new handlebars might wind up approaching the cost of the bike.
posted by Fiasco da Gama at 10:09 PM on October 6 [1 favorite]

I've found Park Tool's DIY repair site to be a pretty invaluable bike wrenching reference.
posted by killdevil at 10:15 PM on October 6

I would recommend the website of the late, great Sheldon Brown as a guide to all things bike. The Zinn book that Fiasco de Gama links to is good also.
posted by nestor_makhno at 10:25 PM on October 6 [1 favorite]

My experience of bike repairs that are all but the most basic (replacing tyres, handlebars, pedals, etc) was that theoretically I _could_ do it. But my job was so crappy that I would prefer to pay a bike shop 30 bucks to do it and have a smooth running bike than spend three hours on it myself, have a kinda badly tuned bike at the end, and probably ruin a pair of pants or t-shirt from grease stains. So ymmv.
posted by smoke at 10:36 PM on October 6

Also, mefi's own bike tutor.

Ignore smoke, he speaks with the devil's tongue. He has no idea of the sublime joy of getting fingers greasy and clinking tools about.
posted by Fiasco da Gama at 10:40 PM on October 6 [1 favorite]

Definitely get greasy (well, with handlebars, not so much) and do it.

Unlike cars and computers, bikes are simple and, more importantly, most of the interacting parts are visible before disassembly, so you can see how things work without having to form as complex a mental model.

Bikes are great for people who have never repaired diddly before. Just use your head, follow a guide book, tighten everything up before your test ride.
posted by zippy at 12:19 AM on October 7

It's definitely something you can learn to do yourself.
If you are serious about being your own bike mechanic, I would seriously suggest you get a repair stand. I do my own wrenching, and it was the best thing I ever bought.
posted by Thorzdad at 5:32 AM on October 7

Before you replace the shifters, replace the rusty cables and adjust them (see any of the references above for how to do that). Delayed shifting is almost always due to 1) shifters/cables are out of adjustment; simple to fix; 2) cables that don't move freely (rust is one possible cause); or 3) whose strands are breaking, causing the cable to gradually stretch until it ultimately fails, usually inside the shifter. 2 and 3 require replacement. It's easy to do and you'll need to adjust the new ones. If you do replace them, stretch them once before trying to adjust them, by pulling them aside like a bow-string, where they are exposed along the top tube.
posted by TruncatedTiller at 5:56 AM on October 7 [1 favorite]

Probably clear, but in case it wasn't, that should have been:
...replace the rusty cables and adjust them the new ones...
posted by TruncatedTiller at 6:00 AM on October 7

Agreed with all above re: you can do it yourself. I started wrenching with zero knowledge, messed a couple of things up, but they were all easily fixable (and cheap) and I know a lot more about my bike now.

You should certainly replace the cables and housing first. Do that, adjust your front and rear derailleurs (according to Sheldon Brown's site, Zinn's guide, or the Utahmountainbiking site), and squirt some lube into the shifter assembly, and I bet your shifting will be miles better in no time.

Past that point? You can do more, but I'm not sure if I'd advise putting that much money or time into a kind-of-cheap off-brand bike. If you want to raise your bars, the right way to do that is getting a new stem or quill, depending on whether your bike has a threaded or threadless headset. (I'd assume threaded, if it was old and/or cheap.) But at that point, you should really start to look around on Craigslist for an older frame that really fits you and swap parts on that. Any quality vintage frame will be much better (and much easier to repair/maintain) than any new, cheapo frame.

Best of luck! Have fun!
posted by aaronbeekay at 7:23 AM on October 7

Being able to replace cables and cable housing is a good thing, but it takes one specialized tool -- a bike cable cutter.
posted by Zed at 7:25 AM on October 7

I would not recommend doing any more work on this bike aside from tuning up the shifting system. It may be tough to hear, but your bike sounds like a boat anchor. It will be much more worth your while to pick up a quality used bike on CL and tune that up. Have any bike geek friends? Let them help your shop. Or send me CL posts that you're eying, and I can give you some pointers. But a bike like this won't last you very long, even if you do get it tuned up.
posted by craven_morhead at 8:02 AM on October 7

do it!! bike maintenance is not hard and will make your bike work so much better.
posted by Large Marge at 9:51 AM on October 7

Being able to replace cables and cable housing is a good thing, but it takes one specialized tool -- a bike cable cutter.

A Dremel or similar rotary tool will work in a pinch without, er, pinching the cable housings. Try spraying the heck out of the shifters with a penetrating oil like Liquid Wrench.
posted by RikiTikiTavi at 9:56 AM on October 7