Mountain Bike Reviews Forum banner

New Chainring or New Crankset?

753 Views 7 Replies 6 Participants Last post by  eric77
Hi guys. I am new to this forum and have found a ton of great info over the last couple days. However, I cannot seem to find an answer to my issue.

I have a 2001 or so Stumpjumper M4 and the middle chainring is bent out of shape. I went to a local shop and they were saying it would be around 80 installed to replace just the ring, but I should replace the whole crankset to avoid future issues. The current crankset is the original specialized strongarm II. I am a pretty big guy at 6'2" 190 and like to ride hard and throw my bike around which is why the tech was saying I should just get a new crankset.

The shop wanted $200 for some raceface crank. I have found an XT M760 for 140, an SLX for around 180, and a RaceFace deus for a little over 200.

I would like to spend as little as possible, but really want my bike to ride as smooth as possible. With all that said, do you think I should just do the middle ring or swap out the whole crank. If I need a new crankset, what would you recommend? Thanks.
1 - 8 of 8 Posts
If you really can get XT760 for 140, don't wait another second.
Unless there's something wrong with the arms, spider or bottom bracket, I don't understand why you'd need a new crankset, assuming it's a 104mm/64mm bolt pattern. It also shouldn't be that expensive to replace just the middle ring - I got an FSA ring for $30 the other day to replace my worn-out middle chainring. Installation shouldn't cost $50, and the ring itself shouldn't cost more than $40. I finagled a little bit of a deal at REI. It's also not a hard task to do yourself if you have the right tools and don't have a compatibility issue. See below.

Issues you need to be aware of... Shimano rings can sometimes have funny shapes around where they bolt onto the crank arm, that will cause you to damage the ring when you try to install it on a non-matching crankset. As in more than just the bolt pattern needs to match. Ask me how I know. Also, most modern multi-speed chainrings have ramps and shift pins to facilitate shifting. Supposedly, they work better if you match brand and put them on with the little marker at the right place. I think this is mostly marketing, especially on the crank, but it could effect your ability to shift from the little ring all the way to the big ring really fast.

Point being that I had a new middle ring installed for $30.

Can you post a picture of your current crank?
See less See more
New crank, new bb and new chainrings on an M760 for $140 is a deal, but if you're not getting the bb maybe not so much. New middle chainring for $80 is silly, unless you're totally unable to change it out yourself.
I've faced this dilemma. It is usually more cost effective to just replace everything
rather than buy new chain rings, BB and bolts.

Just sell off the old used crank set, surely there is someone out there that needs it.
replace the chainring yourself...not very hard, should only need a couple allen wrenches. I'm in that same boat myself right now....I'm just replacing the middle ring. One crappy shift due to poor timing will wreak havoc on aluminum xc chainrings!
An '01 crank is likely to need a crank puller.

OP, do you need a new bb and bolts, or just the ring?
Thanks for all the advice. I ended up calling a few local shops and found one (Adrenaline in Orange) that would swap out the chainring, replace all the cables and tune it up for 85. I just dropped the bike off there this morning and am keeping my fingers crossed that I'll have it by the weekend. I'm strapped for cash at the moment so I really wanted to get this done for as cheap as possible, but next time anything goes wrong I am sure I will upgrade the whole crankset.
1 - 8 of 8 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.