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Always pushing harder!!!
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Discussion Starter · #1 ·
I want to upgrade my crankset for the upcoming race season and need some help on this matter.

This will be my very first racing ever on MTB. I've competed on numerous sports before, but never on MTB, so bear with me here.

Over the past year I've shaved some weight on my bike, an Epic, but I want shave some more. I've done already this upgrades: wheelset, cassette, rotors, handlebar, stem, saddle, seatpost and tires. So now comes the crankset.

Besides numerous choices out there on carbon cranks, I don't want to go on that direction beacuse of the terrain I ride. My stock cranks, XT, cranks have taken a beating...so I don't want to go all out on carbon and damage them on the very first race. I mention this because the biggest hit and chip I've put to my cranks came during training on a course where 2 of the first 4 races are held.

Besides XTR, what other options do I have? KCNC? The lighter, the better...

I might also look into a 2x9...my mechanic, the guy who wants to get me into racing, is suggesting this option because of the way I ride. I never use the small ring. I ride mostly on the 32 and 44.

How does the KCNC compare with the XTR on weight with BB included? What other options are out there?
My XT crank weights 860g without BB, so targeted drop should be in the 100-150g range...
 

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If you're not really into saving the last gram just go with XTR. This is really one of the best cranksets out there and the weight is o.k. Some people complain about q-factor but for me this is more a fad thing presently (sorry guys, just my opinion)

Different story when you want to go 2x9 but on that you can find hundreds of threads here.
 

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Always pushing harder!!!
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Discussion Starter · #5 ·
Anyone with some feeback on the KCNC triple? XTR might be an option, but I want to go lighter. I I want to achieve certain weight with a XTR crank, I will have to go with ceramic BB and that shoots my budget. I'm thinking KCNC maybe and with the extra cash go after the chain and some Ti bolts...
 

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carlostruco said:
Anyone with some feeback on the KCNC triple? XTR might be an option, but I want to go lighter. I I want to achieve certain weight with a XTR crank, I will have to go with ceramic BB and that shoots my budget. I'm thinking KCNC maybe and with the extra cash go after the chain and some Ti bolts...
If price is a bit of on issue check out Middleburn cranks & rings.
 

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quax said:
but for 3x9 Middleburn is quite heavy, additionally you would need a light BB which is quite expensive
Not really, weight on my sons Middleburn RS-7[160mm] with Middleburn 22/32/BBG bash guard,alum chain ring bolts,spider & lock ring = 580 grams.
 

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Freezer
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I just went through the same process to choose cranks for a new build. I compared FSA carbon, Truvative Noir carbon, Middleburn, White Industries, and Paul Cranks. The last three are alloy, so more applicable to you. If you get a light Ti BB (150g) like Phil Wood, the Middleburn is about the lightest you can go, and including the BB, it's much cheaper than the FSA. I have the White Industries cranks on a SS, and they're beautiful pieces too. I didn't consider the Ebones as I read several places that they're pretty flexy. Good luck!
 

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Middleburn rs8 duo 27/40. Cheap, light and works. Best bang for the buck. Run a road front mech with it to maximize your weight savings.
 

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Always pushing harder!!!
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Discussion Starter · #11 ·
Middleburn would be a good option indeed, but getting them to where I live will be a pain...

If I run a 2x9, I'm still crunchin numbers on what to get.

I'll start the season with my current cranks and at mid-season, when budget come around, I'll change to whatever will stay for a long time. There's a bike shop around here that sells KCNC, and those guys there are really good at making bikes as light as possible. The others all carry the same stuff and don't pay much attention to all details involving a WW build.
 

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KevinK
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+1 for the Rotor 3D cranks. Did a ton of research, and although they are not as light as some other cranks, like Lightening carbon cranks, they are a decent weight. However, they are very stiff, currently being used by team Cervelo. One of the best Customer Services around. Any questions, shoot them an e-mail. Rotor USA. I purchased my own chainrings, since I wanted round. Went w/ Specialties TA, Stronglight, and waiting for my Mattias Custom Ti chainring.

Good luck,

Kevin
 

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Q-factor is a fad? Not so sure. There's an entire page dedicated to it in my old Bridgestone catalog (circa 1991). So if anything, it's decidedly not a fad as fads tend to go away.

More specifically, Q-factor may or may not be important, depending on your height. For smaller riders (I'm 5'7"), a narrow Q-factor can give you a more natural stance on your bike. It's becoming more of an issue now (hence why it appears to be a fad) because of the natural backlash against external BB cranks, which are probably more of a "fad" than Q-factor.

As far as which crank to go with, if Q-factor is not a, well, factor, I've found XTR to be the most solid performing crank of the many I've tried. Most recently, I've been on FSA K-Force Light, XTRs, and I'm now running the KCNC triple. I went with KCNC because they were comparable in weight to XTRs (a little lighter, I think), they have a narrow Q-factor and they were competitively priced. I'm somewhat happy with them although my main issues with them are as follows.

They are an absolute b**** to install. You have to lube every last inch of those M-Fers or you will never get the spacing right of the BB cups. I'm pretty handy on wrenching, and I had to reinstall them, no joke, 15 times to get them right, trying various combinations of spacers. I was on the phone with the distributor no less than 4 times before I finally got them on right. Second, they are so minimally shaped that my ankle bangs the drive side arm enough that it causes a pretty deep bruise. I might be able to fix that by switching the spacers yet again, but at this point, there's no way I'm taking those off unless they don't spin anymore. Finally, they chainrings flex under heavy torque.

My K-Force cranks were garbage and if you're worried about banging up carbon cranks, you should be. Mine were in tatters when I finally sent them back to FSA because the crank bolt wouldn't stay torqued. They, of course, did nothing.

XTR is the best crank for the money but I feel like I'm a rodeo cowboy when I ride them. I still have them on my "beater" bike and I never have any other problems. Also, they spin great, just as good as my FSA's w/ceramic BB did. I feel the best option is a BB30 but it will be a couple of years before that platform becomes more widespread. Or the next "fad" as the case may be.
 

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Aren't fads often cyclic in nature? People forget about it and then years later someone sells it again and so on.
However, I'm rather short legged and I never felt any difference between my road bike and my MTB. But I do not want to generalize my personal experience.

Regarding weights of 3x9 Middleburn (add 180g for BB), I don't find 780g really light.
 

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Always pushing harder!!!
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Discussion Starter · #15 ·
tranquilo said:
Q-factor is a fad? Not so sure. There's an entire page dedicated to it in my old Bridgestone catalog (circa 1991). So if anything, it's decidedly not a fad as fads tend to go away.

More specifically, Q-factor may or may not be important, depending on your height. For smaller riders (I'm 5'7"), a narrow Q-factor can give you a more natural stance on your bike. It's becoming more of an issue now (hence why it appears to be a fad) because of the natural backlash against external BB cranks, which are probably more of a "fad" than Q-factor.

As far as which crank to go with, if Q-factor is not a, well, factor, I've found XTR to be the most solid performing crank of the many I've tried. Most recently, I've been on FSA K-Force Light, XTRs, and I'm now running the KCNC triple. I went with KCNC because they were comparable in weight to XTRs (a little lighter, I think), they have a narrow Q-factor and they were competitively priced. I'm somewhat happy with them although my main issues with them are as follows.

They are an absolute b**** to install. You have to lube every last inch of those M-Fers or you will never get the spacing right of the BB cups. I'm pretty handy on wrenching, and I had to reinstall them, no joke, 15 times to get them right, trying various combinations of spacers. I was on the phone with the distributor no less than 4 times before I finally got them on right. Second, they are so minimally shaped that my ankle bangs the drive side arm enough that it causes a pretty deep bruise. I might be able to fix that by switching the spacers yet again, but at this point, there's no way I'm taking those off unless they don't spin anymore. Finally, they chainrings flex under heavy torque.

My K-Force cranks were garbage and if you're worried about banging up carbon cranks, you should be. Mine were in tatters when I finally sent them back to FSA because the crank bolt wouldn't stay torqued. They, of course, did nothing.

XTR is the best crank for the money but I feel like I'm a rodeo cowboy when I ride them. I still have them on my "beater" bike and I never have any other problems. Also, they spin great, just as good as my FSA's w/ceramic BB did. I feel the best option is a BB30 but it will be a couple of years before that platform becomes more widespread. Or the next "fad" as the case may be.
Thanks...this was exactly the feedback I was looking for the KCNC triple...

One question...how are the chainrings holding up? One of the trails I train in, and a race or maybe 2 will be held there, has very large rocks at both sides, so hiiting them with you crank arms or chainrings is pretty common. My Shimano's have been to a few battles and besides regular scratches, they are just fine...
 
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