[BlueGTIguy]

Current setup: Old school Rockhopper (steely) w/ 110bcd crankset (46/36/24). I want the lower gearing of a 44/32/22 crankset and I'm wondering if I can run a nine speed crankset with my current 8 speed setup. I'm thinking either Raceface or Truvativ w/ ISIS bb. Can it be done? Will I possibly need to upgrade anything else in addition to the crankset and bb? Front derailleur? Shifter? Chain? Thanks for replies; hope this isn't a repost.

 

[dflickinger]

Searching "9 speed crankset" in this forum pulled up lots of good answers to that very question. Worth searching yourself but in brief, I think the answers are:

"Can it be done?" Yes, no probs w/ 9sp cranksets on 8sp setups (tho many folks aren't huge ISIS bb fans)

"Will I possibly need to upgrade anything else in addition to the crankset and bb? Front derailleur?" Assuming you're staying w/ 8sp, no. "Shifter?" No. Chain?" Some folks say use an 8 sp chain to match your cassette, others say the wider 8 sp chain interfered with the pins in their new 9sp cranks, so they recommend a SRAM 9 sp chain, which is narrower than 8sp but wider than Shimano 9. Of course, replace the chain if it is worn and you are getting new rings.

 

[BlueGTIguy]

Thanks for the reply; Also, you're right about the searching; I ended up searching "crankset" and found a thread asking a similar question; I apologize for the typical newbiness. So, I'm fairly confident that I can run my choice of crankset, but I've been assuming that ISIS drive problems of a couple of years ago have been largely resolved. I currently have square taper bb; should I try to stick with this? Any bb recommendations?

 

[glenk]

Bottom bracket options

I would think more than likely your existing BB will be a bit too long for a newer square taper crankset like the Deore, but you can measure the spindle length and check. If it's 110 or close, you can just change the crank.

My Shimano 110BCD cranks of late 80's and early 90's were 117MM and 122MM, so I had to replace the crank and BB. Which I used both the Shimano UN53, UN72. I also used a Nashbar BB which is comparable in quality/weight to the UN53 and it's been running for +3000 road miles.

If you have to change the BB, then you have the fun option of going to the newer Octalink or ISIS drives and a whole range of cranksets.

Or you can do like me and just buy a 24 and 34 tooth chain rings and keep your 110BCD crank still going. Your not giving away too much hill climbing ability and the chain rings are easy to find. I like the polished aluminum arms of my older Shimano and Sugino cranks over today's colors. Although I searched around and got flat silver Deores on-line for my other bike.

glenk