it looks to me that the chain runs are riveted together, so I can’t just replace one. but it looks like I can get the set off the crank.
your picture is a bit huge! But your chain rings are riveted, you’ll have to replace the whole crank if you want to replace the rings. That’s the way it goes with the entry level components.
yeah its a bit large, did it with my phone.
bah! i was hoping to just change a ring, so i would basically need a new crankset. I think I’ll be selling this thing next year and getting something better
Yup, unfortunately cranks are one of the components that bike companies cheap out on to meet a price point. The only bonus is you can probably get a new one fairly cheap to replace it to keep you going.
Or maybe someone has an old square taper crank with replaceable rings in a parts bin somewhere. Be aware you might run into BB spindle length issues with different canks.
yeah I figure I would run into some issue, like everything, haha. I’m not even totaly sure yet I have an issue with the chainring, it may be my chain, or a combo of both.
here is the spec sheet of the bike, is that a standard BB? 68 x 122.5mm?
There isn’t really a ‘standard BB’ with square taper. Shell width is determined by your frame 68 or 73mm, spindle length is usually determined by the crank, from 110mm-127.5mm. There are many cranks that use the same spindle length.
I had the same crankset on my entry level Trek MTB years ago. What happened to mine is that the chain rings / rivets sort of loosened up over time and had a load of play and made shifting annoying.
I replaced it with a low level Shimano Alivio crankset. Not a great set, but it was cheap and offered exchangeable chain rings. The crack arms are quite stiff and you can always buy better chain rings over time. I also had to buy a new bearing as well.
That granny ring looks a little hooked to me, for sure. Good riddens to it, I say. Cheap Alivio set can be OK for the rest of the spec. If you are thinking of selling it at some point, don’t put too much into it, and keep the extra dough for the new ride.
that’s what I want to do, keep the expense to a minimum, the bike is only a year old. I’ve only paid to fix one wheel, and bought a set of wheels that I can keep as spares, and I got the bikefor a really good price new. so I’m not out a whole lot, just hoped the bike would have performed a little bit better/ longer
mec.ca/AST/ShopMEC/Cycling/B … ankset.jsp
I bought a set to replace a stripped out crankarm. Not light or fancy, but for $53 they will keep you going for a while
I was looking at that. trying to find a decent used one first, but not much luck. just need something to last the season before I get rid of it. I will probably end up getting the alivio though.
I’ve got the shimano octalink cranks that came on my 2010 rockhopper if they are of any use to you. $40 for the cranks and BB if they will fit your bike.
they both have the same BB size, but the spindle that came on mine is 4.5mm shorter, but that shouldn’t make a difference since the shell width is the same. Can Someone confirm I am correct in saying that?
I also see it is for a 9speed and I only have 8…
I’m a bit of a newb when it comes to fiddling with the gearing.
I’ll check tomorrow. I think I have a couple of Alivo cranksets kicking around that are not getting used that you can have for free.
wow, that would be awesome.
I found one. I can’t guarantee that the rings are better than what you have now, but at least you can unbolt these.
Let me know how to get it to you.
I sent you a pm, dunno if it sent though, it’s staying in the outbox
You have to click send reply. its a bit weird.
alright, so I now have a better crankset (thanks to Turple!!), but when I installed it on the bike the gearset seems to be farther away than my old one, would the spindle length of my bb have someting to do with this? It won’t shift up onto the 2nd or 3rd chainring at all, I havent fiddled with the front derailleur yet. I think tonight I will put the old one on and measure the difference between the frame and each crankset.
There’s a good chart here http://sheldonbrown.com/bbsize.html for many cranksets and the appropriate BB spindle length. You should be able to find the model # of the crank marked on the arms. Alternately you could measure chainline to determine if your BB is too long http://sheldonbrown.com/chainline.html.
You’ll probably have to do some front derailleur adjustment, especially if the chainrings are a different size (i.e. # of teeth), scroll down the page here http://sheldonbrown.com/derailer-adjustment.html for tips. Adjusting front derailleurs isn’t as cut and dry and rear ones, there is a bit of ‘finesse’ involved sometimes.