Bicycle Mechanics - Need new crankset, what is good for cheap??

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
joshbarber89
07-21-10, 01:32 PM
Hello, I have just basically bought my first mountain bike "Airwalk, The Transfer 26" and was not impressed. The whole crankset is mangled and warped from the amount of stress I have put on it, but heres the thing, it was within the first 3 months. So I'm looking to replace, but I'm new to bike parts, and I don't know what kind of crankset I should get via specs. I am also looking for one cheap and reliable so it doesn't fold under pressure. Any suggestions would be great. Here is a picture of my bike.
http://www.airwalkboards.com/wp-content/gallery/Bikes/bike%20transfer.jpg
DArthurBrown
07-21-10, 02:34 PM
The answer you're going to get here won't make you too happy. I don't want to come off as a bike snob, because I believe every bike can serve a purpose, but the bike you have is designed to be essentially disposable. The materials in the components are very very cheap.
If you look for a Shimano Alivio crank, or something similar, you'll have a better crank, but the other parts will probably wear-out very quickly if you intend to do more than ride casually across town and keep the bike in a garage when not in use.
The more cost-effective solution in the long run would be to sell that bike you have, for $50-75, eat the loss, and buy an entry level bike-shop bike. If you spend $250 at a bike shop, you will be astonished at the difference in quality versus what you have now. The $250 bike shop bike will likely outlast your commitment to it if it is properly taken care of.
BCRider
07-21-10, 03:06 PM
You could buy a decent crankset off ebay or similar for around $20 to $30. But I'd second what DArthur above said. Assuming that your bike came from a big box department store the bike is fine for casual riding once in a blue moon but they are just not up to the challenge of even medium use as a mountain bike is understood to be ridden in its proper element. If you're riding fairly hard trails or hitting the local jump park or skateboard park for some air time at all then you do need a better quality bike.
It's actually just about impossible to find out anything about your bike from a quick google. The Airwalk web site is more about bling and VERY thin on any sort of fact. I couldn't even find a section on bicycles if it is even there. And there's not much on the web on any other sites. This does not look good for your Airwalk being a decent bit of gear.
CPFITNESS
07-21-10, 04:35 PM
With that said, search eBay you will find some good truvativ mtb cranks with bottom bracket for $30 which will fix your initial issue but long term you prob need something better.
joshbarber89
07-21-10, 08:09 PM
Thanks for the input guys. From what has been said I'd figure the only good thing left on the bike would be its frame. So I was thinking of maybe building from the frame out.
CPFITNESS
07-21-10, 08:38 PM
many will probably tell you not to, like they told me with my road bike but I say do it. It's a great way to learn and get your feet wet and you can always take the parts and migrate them over to another nicer frame when you get the chance.
In the meantime, if you want a cheap crank replacement, I have bought other stuff from this particular ebay seller
http://cgi.ebay.com/SHIMANO-TOURNEY-8-7-6-SPEED-FC-TX51-CRANKSET-CRANK-SET-/290455131404?cmd=ViewItem&pt=Cycling_Parts_Accessories&hash=item43a079950c
he has a few other better quality cranks for a bit more moeny but $30 to your door aint bad at all
joshbarber89
07-21-10, 09:35 PM
Thanks CP for your effort, but the spindle and all needs a replacement.
BCRider
07-21-10, 10:54 PM
The frame will be a match with the rest of the parts. Unless you can find a tag on the frame that says 7005 aluminium or 4130 or CrMo then there's a great chance that it is just basic high tensile steel or a cheap grade of aluminium. Assuming there is some sort of sticker that indicates what metal is used in it tell us what it says.
Building up a frame with all new parts is NOT a cheap operation. And it's only slightly better if you carefully shop for deals as new specials and decent used parts. So why start with a poor foundation?
CPFITNESS, while I understand where you're coming from if he's going to go to that much trouble he really should find out first if the frame is worth it. I'm hardly a "bike snob" and I fully agree with you that he does not need the top dollar option. But there are just too many limitations in a truly cheap bottom grade frame made from cheezy metal when there are many decent frames just a step up the ladder of frame quality.
Josh, is there any possible chance of returning it for a refund? Even a department store bike should not fold up a crankset in only three months to the extent you seem to have had. If you have some sucess on that track then take your money and run. From there do some studying on what is decent in the NAME BRAND bargain basement. As mentioned even the basic bikes from the proper bike makers will be head and shoulders over what this Airwalk sounds like it is.
snafu21
07-22-10, 01:20 AM
Suntour XCC 170mm cranks. tough & smooth shifting. Takes a square taper (122mm- recommended) B/B. 48/38/28 rings. Take off the old crankset and measure the B/B spindle length and tooth count before you do anything else. I take it you have a triple?
If you've mashed a crankset/spindle interface you may also have mashed the bottom bracket bearings if they were loose. These are good, though:
http://www.chainreactioncycles.com/Models.aspx?ModelID=41902
If you've only mashed the crank/spindle, it's likely that the crank bolts weren't checked a couple of times within a week or so of the bike being new. If you replace the crankset and spindle, re-tighten the crank bolts at least a couple of times in the first month, then regularly.
It's likely - but you'll have to check, a UN54 B/B with a 122mm spindle will fit the frame.
http://www.chainreactioncycles.com/Models.aspx?ModelID=17473
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.