[cummings]

I was riding my bike at the skatepark and I fell and smacked my derailler on the coping in a mini halfpipe. Then after while I was riding, the chain started to skip on the cassette and almost switch gears without me pulling the trigger. I noticed after that my derailler had me riding in the wrong gears.(I have an 8 spd cassette and derailler) Example: my shifter said I was in the 8th gear but my chain was on the 7th. What is the problem and how do I fix it?
P.S. Just by looking at it, I can't see anything wrong with my derailler hanger. I' m pretty sure it isn't bent.
Thanks.

 

[standard235]

Well, if it was in perfect tune before, I have never heard of it being knocked out of tune without bending it..

You could visit www.parktool.com and look at the rear derailleur tuning instructions and see if that will help.

In the 7th cog when it should be in 8th sound like a limits problem.

 

[freerider167]

same thing happens to me. it is still happening to me, infact it's soo bad i need to replace my whole drive train. i think it's the cable and shifter. it's a pos anyway, and if you have a hardrock with the acera der, and deore shifters you might as well replace it.

 

[SHIVER ME TIMBERS]

might need to straiten your derailler hanger

 

[cummings]

might need to straiten your derailler hanger

It's straight. Is it possible my derailler itself is bent? I thought it was always the hanger that bent. If it is my hanger or derailler bent, do I just give it a few good whacks in the direction it should be with a hammer?

 

[SHIVER ME TIMBERS]

It's straight. Is it possible my derailler itself is bent? I thought it was always the hanger that bent. If it is my hanger or derailler bent, do I just give it a few good whacks in the direction it should be with a hammer?

I would have to see what is bent.......I bend with the hand not a hammer.......take it to the bike shop...a quick fix should be free

 

[dream4est]

It's straight. Is it possible my derailler itself is bent? I thought it was always the hanger that bent. If it is my hanger or derailler bent, do I just give it a few good whacks in the direction it should be with a hammer?

take it to your lbs. your lack of experience with this problem may result in a broken hanger. a hammer is not an option here. there are specific tools to do this job. what im saying is that if a minor problem like this brought you here your already in over your head.

if your hell bent (haha) on fixing this yourself call at least three bike shops and pick their brains for advice.
i have never bent a hangar back in 16 years of mtbing. i have had a shop realign my hanger once or twice. very cheap and if you beg a winter slow shop maybe only 10-15 bux.

at least reset the cable and limit screws first. then call local lbs for advice. btw google searches will net you lots or info on derailleur setup/fixes.

 

[dogonfr]

Check your stop screw as suggested earlyer, loosen everthing up then reset up as if installing a new cable. Put your bike in a rack or upside down remove the rear wheel then check your hanger. If all is ok go to the LBS with bike.

 

[cummings]

Thanks for all the advice, I just took my bike to the lbs and my derailler was indeed bent. The guy just took a pair of pliers and bent it back to place. I also needed some major adjusting to get the gears and shifter to match up correctly. I also found out that my chain has a small crack in it(dang it!)The crack is only about 1mm to 2mm long. Does anyone know how long it will last before breaking?

 

[dogonfr]

I also found out that my chain has a small crack in it(dang it!)The crack is only about 1mm to 2mm long. Does anyone know how long it will last before breaking?

What did the LBS say?

 

[cummings]

What did the LBS say?

the guy didn't really know. He said a little while. Does any one have an idea how long it'll last? Looking at it again, the crack only looks like 1 mm. the riding I'm doing right now is skatepark with box jumps if that'll help determine the chains life. Also, should I replace the link/chain now before it breaks to save me from some crash.

 

[dogonfr]

the guy didn't really know. the riding I'm doing right now is skatepark with box jumps if that'll help determine the chains life. Also, should I replace the link/chain now before it breaks to save me from some crash.

Nice mechanic guess that shop is doin too much buisness. You are better off replacing it beffor it breaks all the way, then it'll be a long walk.

 

[SHIVER ME TIMBERS]

Thanks for all the advice, I just took my bike to the lbs and my derailler was indeed bent. The guy just took a pair of pliers and bent it back to place. I also needed some major adjusting to get the gears and shifter to match up correctly. I also found out that my chain has a small crack in it(dang it!)The crack is only about 1mm to 2mm long. Does anyone know how long it will last before breaking?

replace immediately and buy it at the shop that did the work....that helps pay for the time he worked on your bike

 

[jungleuk]

Im with SMT, get that chain replaced immediatly. Putting full pressure on a chain and then having it snap can be a very painful experience.

replace immediately and buy it at the shop that did the work....that helps pay for the time he worked on your bike

I

 

[Tracerboy]

what is ur bike set up, if it is a bike that you use to ride mostly downtown and doing urban and stuff like that than go single speed, cheeper than buying a new deraileur and also more reliable

 

[Guest]

Putting full pressure on a chain and then having it snap can be a very painful experience.

ohhhhhhhhh yes

 

[standard235]

ohhhhhhhhh yes

Try it clipped in on a BMX bike at 25mph on pavement...

 

[sflett]

you could just replace the link in the chain, if the chain is relatively new, but if you dont know how to do this yourself, then just buy a new chain and the shop should install it for you for next to nothing.

to check your chain wear, put it in the biggest chainring, and and grab the chain on the very front of the chain ring. pull towards the front tire, and if the chain pulls far enough away from the chain ring that the space is longer than the teeth on the chain ring, THEN GET A NEW CHAIN you can also just measure it. i believe its 12 links=12 in. google that one though.

 

[SHIVER ME TIMBERS]

you could just replace the link in the chain, if the chain is relatively new, but if you dont know how to do this yourself,
.

no no no....if the chain is that damaged...no matter what replace the whole thing....chains are cheap and it is not worth breaking down

 

[Tracerboy]

Try it clipped in on a BMX bike at 25mph on pavement...

y were u cliped in on a bmx bike on the pavement?