Clydesdales/Athenas (200+ lb / 91+ kg) - Upgrading Cranks / Cassette

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View Full Version : Upgrading Cranks / Cassette


Fleet
08-20-07, 06:54 AM
Hello everyone,

I'm continuing on my quest to upgrade my Specialized Hardrock mountain bike. So far, I've swapped out the fork from the Suntour to a RockShox Tora 318, with great success. Really a great upgrade.

Now I'm looking to upgrade the Crankset since the stock one is starting to fail. In fact the Bottom Bracket really needs replacing right away - the bearings are shot. I can get a new BB for about $25, but I noticed the right crank arm is cracked, so its time to move on, and move up. I'm pretty sold on a Shimano LX M580 crankset with the external BB.

I was also thinking it might be a good idea to replace the Cassette as well while I'm at it. But here's the issue. My hardrock is 8-speed, and the corresponding LX M580 Cassette is 9 Speed. I like 8-Speed. I have no use for the extra 3 gears, and would hate to replace a bunch of corresponding parts to accomodate a new cassette. What would I need to replace? (Crank, Cassette, Shifters, Chain, Frt Derailer, Rr Derailer?) Ouch. That's getting expensive and extensive.

Any advice on this upgrade path? I don't have $400 to put into this bike. I have around $200 and the M580 crank is $140. I'll also need a new chain, I'm sure. Are there other alternative for a new 8-speed cassette? Or is there a better combo I should be looking at besides LX Cranks / Cassette? I would like this bike to last another 3 years. For all I know, the crankset/chain is all I need.


jaxgtr
08-20-07, 07:20 AM
Just buy an 8 spd Shimano cassette, it's not a big deal. I run a Ultegra 12-23 on my hybrid even though I pulled off a 11-34 SRAM. You will just need to replace the chain. It's pretty painless.

bdinger
08-20-07, 09:31 AM
Sounds like a good route to take. I was going to do the same with my Hardrock, but the shop I bought it from is going to replace the Truvativ BB at their cost (this was so odd, I didn't even complain, I just asked if they carried them) with free labor. BUT, the LX crank is a good choice, that was one I was looking at.

As far as cassette/chain, get a SRAM cassette and a SRAM PC-68 (IIRC) chain. I've heard good things about both. Heck, the SRAM cassette on my Trek FX looks nearly new, with almost 1000 miles on it. The Hardrock.. notsomuch :)


Bill Kapaun
08-20-07, 02:20 PM
To go to a 9 speed cog, you'd have to replace the rear shifter also. Other stuff should still work.
There are different ratios available if that's what you meant by "options". Here's just some of them-
http://sheldonbrown.com/harris/k7.html#8

Fleet
08-20-07, 03:04 PM
Thanks for the replies. I'm getting a little clearer in my head in regards to whats required for an upgrade. I'm going to replace the cranks for sure. The chain is a no-brainer too. That's $20. The cassette is pretty cheap at 8-speed, so I may just replace all 3 pieces - crank, chain, cassette.

It is very very tempting to just "upgrade" to 9-speed if its just replacing the shfiters on top of that.

I'm trying to practice self control, though.

clearwaterms
08-20-07, 03:29 PM
Thanks for the replies. I'm getting a little clearer in my head in regards to whats required for an upgrade. I'm going to replace the cranks for sure. The chain is a no-brainer too. That's $20. The cassette is pretty cheap at 8-speed, so I may just replace all 3 pieces - crank, chain, cassette.

It is very very tempting to just "upgrade" to 9-speed if its just replacing the shfiters on top of that.

I'm trying to practice self control, though.

comparing the xt 8 spd to the xt 9spd, I don't see much advantage to the 9 speed setup. all it is is a 34 tooth big gear. so unless you use first gear alot now that you need to have a 34 and a 30, i wouldn't waste the money (thats just me though)

jaxgtr
08-20-07, 05:29 PM
comparing the xt 8 spd to the xt 9spd, I don't see much advantage to the 9 speed setup. all it is is a 34 tooth big gear. so unless you use first gear alot now that you need to have a 34 and a 30, i wouldn't waste the money (thats just me though)

You know this is a good point, I did not think really think about that. I guess I will just stay with my 8 speed when I upgrade my crank and derailleurs sometime next year.

(51)
08-20-07, 06:18 PM
You will just need to replace the chain. It's pretty painless.

I haven't changed a chain since I was a kid. Back then there was a "Master Link" that had like a clip holding it on. How do you go about doing it these days? I guess I could Google it :rolleyes:

CastIron
08-20-07, 06:30 PM
Park Tool (http://www.parktool.com/index.asp) will walk you through every procedure in detail on their website (http://www.parktool.com/repair/)for free. They also make the tools you'll likely need to use. Good stuff, too.


http://www.parktool.com/images/products/productimages/det_CT-3_002_2007511_75346.jpg

jaxgtr
08-20-07, 07:10 PM
^^^ +1

Takes about 10 minutes to change it out. A full size chain tool is better than the small emergency tools for sure.