Bent my pedal sprocket today - how to fix?
 

When changing gears I was pushing too hard, which made the chain derail. Then i cranked again before noticing, and it bunched up, and bent the middle sprocket pretty badly.

Is this an easy part to replace for a biking newbie with decent mechanical skills? It is the middle sprocket on the front (pedal) crank.

Or should I just let my lbs fix it?

(I hope my chain didn't get bent - it seems to work fine when not on the bent sprocket, so...hopefully it didn't!)

Are you able to replace individual rings? Or is the whole thing an assembly?

Replace the damaged chain ring. If you are not sure of the bolt pattern, take the chain ring to your LBS.

Assuming he has replaceable chain rings.

I managed to get the biggest chain ring off without taking the pedal crank off.

I tried to get the middle (bent) one off without taking the pedal crank off but it will not go off because it is too small to clear the pedal crank (it can't clear the 4 arms that are used to hold the large chain ring on)...

So I loosened the middle screw that holds my pedal crank on and took it off.

Now I am trying to take the pedal crank off, but it wont budge.

Do I need a special tool? I was thinking of prying it off but I really don't want to damage anything with a hammer or screwdriver..............

Any help would be appreciated this seems like an easy job but I cant get the pedal crank off. It looks like it just slides on and off onto some square piece that sticks out of the bottom bracket.

the bike is a 2002 rockhopper comp fsr xc

You'll need a crank puller, they're about $15.

This is one here, I have one and it gets ALOT of use. Mine is a axiom one but I havent been able to find it online.

http://www.parktool.com/products/det...6&item=CCP%2D4

damn, there's always some kind of special tool involved...grrr...

My crank has a square hole thing going on......Would that crank tool you linked work on my bike?

legalize what? :D :D :D

I would bend it back.

Beneficial plants.

Yeah I may as well TRY to bend it back at least...

Im surprised it was so easy to bend. Damn. You'd think theyd at least heat treat these things so they would be strong.......

+1 Your biggest expense will be the crank puller. I don't see how you can do this job without it, maybe someone else can explain that.
My son's bike had a chainwheel bolt loosen, then dislodge right into the crank. When he pushed down on the left pedal he rammed it home and bent the middle chainwheel so bad I was sure it was toast. I pulled the chainwheel crank, disassembled the chainwheels, took a 12 oz hammer and straigtened it. Amazing, this process actually works pretty well. It was a bio-pace chainwheel too. I'm not sure if I read that this was the acceptable practise in Sheldon's website or from Todd Down's book, but before you trash that gear, you should try straigtening it.

I've done it on motorcycles (dirt bikes), and usually with the sprocket on. Hammering on a flat surface is best, but a couple pairs of pliers and some TLC goes a long ways :D

Won't the middle chainring come off if you remove the pedal instead of the whole crank arm? I'm pretty sure it should come off with the pedal removed but maybe not for all cranks/rings.

No, the problem is not the pedal. THe thing it cannot clear is the 4 "arms" that come from the pedal crank which are used for the 4 bolts to go through (which in turn hold the largest chain ring onto the crank arm)

Were you able to bent it back, or will you have to pull the crank?

Im not going t try bending it back. Itll just come out ****ty and i dnt even have plates to clamp it with vicegrips with

just going to bring it to the bike shop instead of paying 14-25 for a crank puller that ill barely ever use

If I learned anything tonight while surfing the web its the name for those arms your talking about, they are called the "spider" ooo scary!

link:

http://www.sheldonbrown.com/gloss_sp-ss.html#spider

It is going to take 4 days for them to do this simple job, I can't believe it

The middle chain ring will cost 30 bucks!! Am I getting ripped off by the lbs? It's a shimano chain ring, looks the same as what I have.

Plus 15 in labor

Damnit, I feel so taken!

grr

Prices are normal, 4 days is BS. This is a 10 minute repair, if they're that backed up they shouldn't take in new work. Call another shop.

normally i would bother but its going to be raining for the next 3 days anyways and it has been raining nearly nonstop for 4 or 5 days. the trails have giant puddles in them that go up to your waist or knees, lol.

but yeah 4 days is so lame.

As a wrench in an LBS, I have to say four days is not bs at all. Actually, at this time of the year, it's pretty good. Everybody in the north waits until the last minute to bring their bikes in for Spring tune-ups and other work. Things tend to pile up. My shop is now three days out, but I have heard of shops who are five weeks out right now.

Yeah, it is probably a 20 minute job. But, there are also probably 50 people in front of him who also need work done. Remember, it is first come, first serve. So, what is the wrench supposed to tell all those other people when he jumps a repair to the head of the line?

If it is a good shop, they are underpromising and over delivering. It will probably be done sooner.

And as for not taking work in, be serious. LBS are a business. If you tell someone to take their work elsewhere, they will. That's lost business and lost revenue. Not good.

I have to say, I have never understood this I want it and I want it now attitude. I would hope nobody wants a rush job done. You want it done right. Sometimes, that means waiting a little while.

This is why I do my work myself. You either

a. Invest (yes, invest) $15 in tools, or
b. Go to a bike shop (1/2 hour at least), using $3 (at least) of gas, spend $30 for a new chain ring, $15 for labor, etc. Assuming you make $20 an hour (just a rough guess) that is $68 spent right there.

At my shop, I never have any lines, and I always get things done exactly how I want them. The worst is when I have to wait a few days for a mail-order part to come in.

I understand how shops work, I'm just telling the OP to go to a shop that can take care of him. Nobody should have to wait 4 days for a 20 minute job, and shops that expect customers to wait that long for simple work should expect customers to go elsewhere. Getting backed up 5 weeks with routine stuff? Give me a break, did they expect that the spring rush was going to come in August this year or something? It's not like it's unpredictable. If you got slammed with last-minute spring tuneups, and you didn't send out a 15% off spring tuneup postcard to all the customers in your DB back in April, congratulations, you know more about bikes than business. If you don't beef up your staff this time of year with a half dozen high school kids who know how to swap out a bent chainring, you're not doing good business, and if you're still taking in anything but specialty work with over a month of backlog sitting around you're screwing over the customers that most LBS claim to pride themselves on taking care of.

I'm sorry, I like local shops and all, but I'm tired of the attitude that a LBS deserves anyone's business by sheer virtue of existing. Don't support local shops that don't support you. It's not about an "I want it now" attitude, it's about not having to put up with excessive waits because a business is poorly run.

i really hate giving my bike to someone to fix, just as i hate bringing my car to someone to fix. probably because i could do it on my own and not get screwed out of labor rates. plus, you can't exactly trust anyone. i guess this is why i should invest in tools and start learning how to fix bikes.

they called and said my chain isnt bent but i need a new small ring too, because it is slightly bent and the chain skips under torque. it should be ready today though they said, which means it only took a day. i guess that isnt bad.

Agreed! That's why a previous poster is exactly right to say that tools are an investment, not an expense. You'll need that crank puller when it's time to service or replace your bottom bracket too. And when you can do your own maintenance and repairs, you can do them instantly instead of having to wait, and save a ton of money each time.

yup. i plan on trying to do that from now on. this whole experience (replacing 2 chain rings) cost 61 bucks. (15 for labor, 30 for middle chainring, 15 for inner chainring)

great news! I took the bike out and the chain slips, rubs, and makes noise on 3 certain gears!

can't bring the bike back today because they're closed!
can't bring it in tomorrow because i have work!
thursday is the first nice non-rainy and warm day in more than a week, and that will be the day I bring the bike in

GREAT. god i ***ing hate this sh it. why didn't they fix this or know about this when THEY WERE WORKING ON IT???

just like a freaking car shop, this bullsh it. i need to learn how to fix bikes fast so i dont have to rely on these bast ards. GRRRRRRRRRRRRRRRRRRRR