Bike problems: I can't peddle *SOLVED*

Magic Pink

About 3 or 4 months ago my bike started making loud grinding noises whenever I peddled and I was slowly losing forward momentum. It was really hard to peddle as well, like I had cranked the gear up to crazy level. I took it in and they replaced some big ol' part and the grinding noise was less (but still there) but I had all my momentum back and peddling was back to normal.

Flash forward to today where the problem is starting all over again. What the heck is wrong with my bike? I had it for a good 5 years without this problem. Do I get it repaired again or just junk the thing and get a new one?

Skoal Cat

I guess that depends on how much money you can spend and if the bike was any good to begin with.

Magic Pink

It was and I have plenty. I just don't want to have to constantly get this repaired over and over.

EggyToast

What's your maintenance routine like? How often are you oiling things and replacing bits? how many miles do you put on a week? are you a steel frame or aluminum frame? what kind of brakes do you have?

Magic Pink

No maintenance at all. I do squirt some lubricant on the gears every so often. I ride them till they something needs fixing and then I take it in. The other questions: I have no idea.

Darkewolfe

Where in the drivetrain is the grinding sound coming from, up where you peddle or back where it drives the wheel? Is the grinding louder when you shift gears?

I'd prop the bike up and use your hand to get the wheel going, try to figure out where exactly the sound is coming from. It'll help a lot to know if it's a problem at the cranks, or if it's something simple and silly like the derailleur being misaligned and grinding on the chain.

Magic Pink

It's definitely in the peddle itself. If I'm coasting or going downhill it's fine. No matter the gear, as soon as I hit an incline the grinding starts, loudly, and I lose momentum and peddling gets really difficult.

Wulf

I had an issue like this with my bike when I was trying to change gears and the chain hadn't fully engaged. Does the bike make a loud popping grind when you try to shift?

matt has a problem

It sounds like the bearings in your bottom bracket are going/have gone bad.

http://en.wikipedia.org/wiki/Bottom_bracket

Basically that assembly between the two pedals needs to be replaced.

:edit: Also, "peddle" usually refers to a traveling saleman, "pedal" is what you're doing on a bike. Just, you know, grammar pedant...

BlindZenDriver

matt has a problem wrote:

It sounds like the bearings in your bottom bracket are going/have gone bad.

My guess as well. Lifting the chain of the chainrings will tell because then the crankset can either rotate with pretty much no effort or something is wrong. It may be that just some lube and adjusting in the right place is enough to fix the issue but most likely the bearings are dead and a new unit is likely needed.

I suggest stopping by at the local bike shop because some special tools are likely needed.



PS. While you're at it make the LBS check the whole transmission for wear.

Magic Pink

matt has a problem wrote:

It sounds like the bearings in your bottom bracket are going/have gone bad.

http://en.wikipedia.org/wiki/Bottom_bracket

Basically that assembly between the two pedals needs to be replaced.

That's what they replaced last time but then it only took 3 months and I have the same problem again. So back to my original question: Do I get this repaired again or get a new bike?

Darkewolfe

You never need a new bike, ever really, unless the frame itself is cracked or warped, and even then you could theoretically just replace the frame. That's why people asked if your bike is a nice one. If it's a decent bike, it'll be cheaper to replace damaged parts than buy a new one. If it's just a box bike from a retail store you might be better served just replacing it.

I'd recommend going to a different bike shop, not explaining the situation so far, and just letting them know about the noise and asking what they think should be fixed. Might be a second opinion from a bike pro who may or may not have a better fix on the problem would do you well.

Jebus314

Magic Pink wrote:

matt has a problem wrote:

It sounds like the bearings in your bottom bracket are going/have gone bad.

http://en.wikipedia.org/wiki/Bottom_bracket

Basically that assembly between the two pedals needs to be replaced.

That's what they replaced last time but then it only took 3 months and I have the same problem again. So back to my original question: Do I get this repaired again or get a new bike?

Your first step should be to take it back to the bike shop and tell them it isn't working again. Unless you had an accident somewhere along the line, your bottom bracket breaking after 3 months seems like a shoddy installation. It's worth at least trying to get the shop to repair it for free since it should not have broken so quickly. At the very least they might be able to indicate why it seems to be breaking all the time, at which point you would know what needs to be replaced.

As for getting a new bike vs repairing, the truth is bikes are so easily taken apart that it never really makes sense to ditch the whole thing. The only reason to replace a whole bike is if the frame is damaged or if you damage all your parts in an accident. If you find out that the frame is damaged, and that's what's breaking your crank set, then it would still make sense for you to remove the parts and keep them for your new bike, or trade in/sell your old bike.

Donovan Puppyfucker

It might not be the bottom bracket this time, it could be the rear hub.

Seconding the advice to take it back to the shop you took it to last time to get them to look it over again.

Magic Pink

Turns out my rear wheel had becime unseated (after getting sideswiped by a bus a few days ago) and it was rubbing againt the chain casing. The grinding was actually my seat post full of grit, having never been greased when the bike was put together. Why the grinding was loudest when I was peddling up-hill... no one knows.