[berry79]

Well with my birthday is coming up next month, the wife has been asking what I would like. So i'm going to take advantage of this opportunity to do some more upgrades to the bike. The first will be the fork and second, the item in question, will be the crank. After doing some searching here I see that crankset designed for 9 spd cassette will work with 8 spd cassette. My question is will the cranks designed for 9 speed also work with a 7 speed cassette? Also, I currently have a 42T ring gear up front and it seems that alot of new cranks come with a 44T outer gear. Will this 2 teeth increase mean I would need a longer chain or would my current length chain be long enough?

 

[TwinBlade]

It will work with a 7 speed and going up 2 teeth will have no impact.

Your shifter only shifts so many times, that is why it will work. Think of it only shifting 7 of 9 gears. 2 teeth adds a negligible amount to the diameter and will impact nothing. :thumbsup:

 

[rlouder]

Since 7 and 8 speed drives use the same width chain, I would think a 9-sp crank will work with a 7-sp cas.

Since your adding 2 teeth of gearing, you would want to add two links to the chain. It's a good time to replace the chain anyway, especially if your rings are worn.

See parktool: http://www.parktool.com/repair/readhowto.asp?id=26

 

[TwinBlade]

I just went from a 42 to 44 top gear myself and changed nothing and it is flawless. Not arguing, just sayin'. :thumbsup:

 

[berry79]

Thanks for the help. Nothing should be worn. I've only had the bike for 2 weeks. I had what I thought was a creaky BB the other day and took it back to LBS. They said it was a little loose and tightened it up. Went for a ride today and after a few minutes of riding the noise came back. Everytime it creaks I can also feel it kind of poping. I replaced the pedals to rule those out and I'm taking it back to my LBS tomorrow. If this is what I can expect from my stock crankset on my 2010 hardrock, it will be getting replaced with an upgrade.

 

[captainjoon]

Originally, all bikes have chains installed with 2 or 3 link slack. Likely there won't be a scenario where you would need to use the 44t front with the 34t(or which ever is the biggest cog) rear but the slack is there as a safety.

I wouldn't worry about the 2 additional teeth to the chainring, but if you want to do it properly you would need to add 2 links to the chain.

But to reiterate, likely you won't need to use a 44t/34t combination so ignoring the recommended slack is OK.

 

[rlouder]

I just went from a 42 to 44 top gear myself and changed nothing and it is flawless. Not arguing, just sayin'. :thumbsup:

It probably works okay since one should never use the big ring with the bigger cogs anyway, but I always try to suggest ideal methods.

 

[TwinBlade]

It probably works okay since one should never use the big ring with the bigger cogs anyway, but I always try to suggest ideal methods.

I hear ya friend. As a machinist, I always strive for "mean" on my tolerances as well. :thumbsup: :thumbsup:

 

[rlouder]

It sounds more like a bottom bracket problem than a crank problem. I've read a few recent posts where people are having the same problem with new hardrock bb's. Look around for them.

Since it's that new, I would want the lbs to fix it properly. That may mean replacing the bb.

 

[berry79]

It sounds more like a bottom bracket problem than a crank problem. I've read a few recent posts where people are having the same problem with new hardrock bb's. Look around for them.

Since it's that new, I would want the lbs to fix it properly. That may mean replacing the bb.

Thats what I was thinking. I just figured I could get a new crankset that came with a BB and be done with it. My LBS are a bunch of good people so I'm sure they will do whatever it takes to make it right. I just have this problem with all my hobbies that I can't just seem to leave stuff alone and I'm always changing something. I know with the money I'll spend on upgrades I could have bought a bike with better components. But, by doing it this way I figured I could learn to wrench on my bike and know everything else about it. Who, knows after the upgrades, I could always just buy another frame and transfer components leaving me with 2 bikes

 

[bad mechanic]

Have the LBS fix the creak, and spend the money and opportunity on more worthwhile upgrades. A good one would be new tires - install Conti Race King SS 2.2 tires with Performance Ultralight tubes, and you'll drop close to two pounds of rotating weight, plus it'll grip better, plus it'll roll a lot faster.

 

[safme]

I changed my stock crank 42x34x24 on my 2009 hardrock to a Deore 44x32x22 and had to change the front dérailleur due to the cage rubbing on the middle ring.

 

[berry79]

I changed my stock crank 42x34x24 on my 2009 hardrock to a Deore 44x32x22 and had to change the front dérailleur due to the cage rubbing on the middle ring.

I read about that as well. I guess I'll have to change that too. I see the race face has an adjustable chainline. I might try them on the smallest chainline setup and see if the factory FD will adjust out that far I believe the raceface can go down to 49mm and I think the hardrock is set up at 47.5.

 

[rlouder]

I think you have been bitten by the upgaditis bug. bad mechanic makes a good point. At most, I would have the lbs upgrade the bb and look at more worthwhile upgrades to sooth that bug bite.

 

[berry79]

Had the LBS fix the problem. Turns out it was the chain. They took care of it free of charge and now it's smoother than ever. I plan on upgrading the tires myself probably within the next week or so. But, no doubt the upgrade bug has bitten. I'm already scouring craigslist for a disc brake wheel set and who knows what will be next.