Kuakeye

I have an old Trek multi track hybrid that I want to repair to the point where I can use it as a winter beater/commuter bike. Currently, the bike has several issues and I am a novice at bike maintenance/repair.

1. Headset is loose and wobbles slightly. I can probably try taking this apart, clean out the bearings, and tighten everything. However, is it worth it to replace the bearings inside? Where would I even find new bearings?

2. The back wheel tube keeps popping. It lasted for a full year before violently exploding while (thankfully) stopped at a stop light. The replacement tube violently exploded a week after replacement, leading me to think that I probably replaced it wrong and the tube probably pinched against the tire or something. Not entirely sure what happened. I'll need to take a look at the tire to see if any sharp bits got lodged into it causing the tube to pop. I'll also look at the rimtape to see if it's damaged/any spokes poking through. From looking at it currently, rim tape looks pretty new, and tire looks like it's in pretty good shape though....

3. The back wheel became out of true after a car decided to take a sharp turn as I passed by, T-boning me...didn't hurt me, but the back wheel took a bit of a dent. Took it to a LBS who tried to true it but could not do it completely, so trued it to the best of their ability free of charge! Wheel is now OK, wobbles side to side ~1/2 a centimeter. Could the back tube be popping so frequently due to the wobbling untrue wheel at all? Since this bike is old and will be used as a beater, I really don't want to invest in a brand new wheel...

4. Back wheel brake cables somehow got severed...no idea how this happened but I figure I just need a new set of brake cables. Brake pads still have some life, maybe 40%.

5. LBS said the bottom bracket bearings need to be replaced. Not sure what this entails, how to check for signs of wear. What happens if I just ignored this? Would the bike still be functional? (LBS quoted a maintenance overhaul with new bearings, new wheels at around ~$500. NO WAY! I paid less than $100 for this bike!)

The front wheel is old, but works well. Drivetrain works pretty well, almost no corrosion since I cleaned it pretty frequently. Ever since I got a nice road bike, this bike has been sitting in the garage in disrepair for half a year now. Is there any hope for this bike? I'm on a pretty tight budget so I'd like to spend minimal money on new parts. I'm thinking new tube, new brake cable, maybe new headset bearings, that's it.

maddog34

is that bottom bracket rough feeling? if so, REPLACE it before it comes apart on you.

look through your local Craigslist for a used rear wheel.

cables are easy and inexpensive.

you seem to be well on your way to learning about tire/tube issues.

headset bearings are cheap and plentiful... getting the headset adjusted correctly can be tricky, but you'll figure it out... once you have the big, thin wrench(s)

JohnDThompson 

If you're going to the bother of opening it up and cleaning it out, you may as well do it right and replace the bearings while you're in there. The most common sizes for headsets are 5/32" and 3/16" If you know the make and model of your headset, you can probably look it up, or ask someone here; otherwise take a ball to the bike shop and they can measure it for you and sell you the proper size. Some bearings come in retainers; you can replace the whole retainer/ball assembly if you like, or use loose balls. Loose balls may allow more balls in the race, which spreads the wear over more balls, but are a little trickier to assemble.Fill the race until full, then remove one ball. Grease can hold the balls in place while you assemble everything.

Violent tube failures are almost always installation errors: the tube gets stuck under the tire bead and eventually extrudes out and bursts. Sometime a casing failure in the tire itself is responsible, so check for that as well.

Untrue wheels don't lead to tube failures. As long as the rim can pass through the frame and brakes, you can ride it, but it's not ideal. Put a new wheel on your Xmas/birthday list.

If the pads are more than a few years old, they can be hardened and less effective.

For a while it will work, maybe even quite a while. Servicing bottom brackets requires a few specialized tools, which ones you need depend on what type of bottom bracket you have. If you have a cartridge-type bottom bracket, these are not generally serviceable, so when they fail you replace the whole cartridge. Cup-and-cone type bottom brackets are serviceable; you remove the lockring and adjustable cup from the non-drive side, slide the spindle and bearings out, and inspect for wear and damage, replace parts as needed. Spindles wear faster than cups, so look for pits in the bearing track of the spindle. If there are none, repack with fresh balls and grease and be happy. If you do find pits on the spindle, check the cups to be certain they're ok (often they will be), and replace the spindle with one having the same measurements. There are often arcane markings on the spindle that can be used to find compatible replacement spindles.

SkyDog75

Great bike for that kind of duty.

If you disassemble and the headset parts look to be in good shape, you can probably just clean, apply fresh grease, and reassemble/adjust. If you want to use new balls, you can pick 'em up from your local bike shop cheaply enough. If you don't have a local shop, you can order bearings from plenty of places online.

Tubes generally don't rupture without a reason. You can often tell by examining the tube what the reason is. Where did it pop? Tread side, rim side, or sidewall? What's the hole look like? Punctures are often small holes. Blowouts or tears often mean the tube got outside the tire somehow, like through a spoke hole or being pinched by a sidewall. Pairs of "snake bite" holes often mean the tire was underinflated; air pressure can't support the rider and the tire & tube get pinched between the rim and pavement.

An out-of-true rim won't cause punctures. But if there's other damage, like a crack, maybe. I don't think that's a likely culprit, though.

A rim that's that far out of true might cause some braking weirdness, though.

New cable, maybe new housing. Easy job.

No way should you spend $500 overhauling a Trek MultiTrack. You can get another one (or two or three) in great shape for that money.

The bottom bracket, in a nutshell, is the bearing assembly where your crank spins. If it's worn, you may notice some play as the cranks spin, or it might feel gritty. You likely have a Shimano cartridge bottom bracket, which is about $20, as is the tool you need to replace it.

As for wheels, you should be able to find a used 700c hybrid wheel reasonably cheap. Or even a donor bike you can transplant the wheels from. You can even buy a new one in the $30-50 range IIRC from sources like Niagara Cycle. (Not sure what shipping will set you back.) And Nashbar sometimes has sales on Vuelta wheelsets.

Kuakeye

Ok so I examined the damage on the back brakes and it turns out one of the cables for the cantilever brakes have been severed. I looked around online and saw many different types of cantilever brake straddle cables, all with different sizes and rating types. I'm completely lost now.

xenologer

"$500"

The way I see it, you get what you pay for with bikes.
either buying something new and expensive that works well
or something used super cheap then pouring money into untill its fixed

either approach, expect to spend about the same in the end if you want a good ride.


of course the exception to that rule, is if you know what you're doing mechanically and can fix things yourself and have access to parts. Then the former path of buying cheap and fixing has significant savings.
That doesn't apply to you though.

Support the shop, have them do the repairs.
60$ for a bottom bracket replace
100$ to replace the damaged rear wheel (leave the front wheel alone if its not a problem)
30$ rear brake job
well, maybe not the shop you described, since their bid is too high
but some shop someplace that matches those prices is a good value.

hokiefyd 

Cantilever brakes can be tricky. If you can, try to match what's on the front (regarding the straddle cable). The Shimano yokes are derided by many, but are easy to setup. If the front has a Shimano cable (with the little black "coin" at the junction), it probably has a letter code on the back.

Sheldon Brown has a page on the theory and math involved with cantilever brakes: https://www.sheldonbrown.com/cantilever-geometry.html. It's a good read if you're interested, but the info you need is a little more than halfway down. It shows the various lengths of straddle cables. My bike shop doesn't stock these anymore (I suspect few do), so you may have to get them online.

I have a similar bike (a 1997 Trek Multi Track 750) and I converted it to V brakes. This is additional work, but I feel the results are worth it. If you PM me, I can help you with the details on that.

I agree that $500 is way too much to overhaul this bike. That's retail price on replacing a ton of parts that probably don't need it. Your bottom bracket should be a cartridge type bracket that is available for less than $20 (plus the tool, as noted above). The brakes should be relatively easy to sort. Regarding the headset, I'd be inclined to simply grease and go, unless you feel that the bearings need replacing. If it's SUPER loose, it likely had water and other junk inside. Still, bikes and their parts are very resilient. Some new grease and the right adjustment will likely put it back to near-new condition.

nfmisso

A Trek 720 with canti brakes is a great bike; nice light and strong cro-mo frame - surprisingly, lighter than the tig welded double butted cro-mo 930. The frame is well worth having decent components installed if it fits you. My primary commuter is a Trek 720; I purchased the frame and fork for $25-; the handle bars cost more than the frame & fork. It is set up with a 1x9 drivetrain.

Kuakeye

Replaced the back tube of the bike and examined the damage on the old tube. It seems like the failure point of the old tube is right next to the valve. There is a pretty substantial cut there almost halfway around the circumference of the stem. I wonder what caused that...
Hopefully this new tube will hold up better.
Anyone have recommendations for an inexpensive bike tool set that I can buy that will give me all the bike specific tools I'd need to do a more comprehensive repair? I tried to tighten the headset but realized that I would need a much thinner and larger headset wrench. It would also be nice to have one of those long wrenches to screw in pedals in the future, as well as a tool to take casettes on and off. A tool to service bottom brackets would be really nice too. As well as a wheel truer...Otherwise, I'd also be willing to purchase some things separately as well