[JohnEZ]

I posted this - following is Doc Nolan's response... comments? XTR lovers say they shift better. I have XT cranks (square taper) that are two years old on my other bike, and they are rock solid.

So, XTR or XT?
4 arm or 5 arm?

XTR $225 vs. XT $90 (4 arm). As for 4 arm vs 5 arm... the 5 arm XTR is not be had on sale, best I've found is $325. Also, it's hard to find. And the rings are harder to find for the 5 arm.
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Posts: 86 | From: Houston, Texas | Registered: Apr 2001


Paul K. Nolan, MD

Member # 12
Member Rated:

posted 11-14-2001 11:01 AM
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JZ:
Unless your are a big gear masher, which I would not recommned for anyone over 30 who wants to stay friends with his or her knees, the XTR cranksets put you at a disadvantage for the higher gearing ratios you will be stuck with (24-36-46 or 24-34-46)and greater weight XTR 685 gm vs XT 647gm. (By the way, if you think you can just use the 11-34 nine speed XTR cassette to get decent granny gears, you best check your family jewels at the door because that alloy 34 tooth granny is going to blow on you at a very inopportune time; see previous post from Charlie as well as my frequent rants on this topic.) The XT hollow tech crank is a lighter, stiffer, and far more affordable crank with a pretty bullet proof bottom bracket. The XT BB is 42 grams heavier than the XTR bottom bracket but since the weight is in the shell, it is not rotating weight, so the lighter XT crank set wins out in less rotating weight. So unless you find yourself consistently spinning out the cranks on the compact drive set up (22-32-42) you gain no great advantage with the XTR cranks except showmanship. However, you do gain high marks for common sense and useful frugality with the XTs.

With that said, if you really have to succumb to the style mavens, you can get 5 arm chain rings for the XTR cranks (74/110 bolt circle diameter) without too much difficulty. Most decent bike shops have access to suppliers that stock 5 arm chain rings. I keep a good representation of them in my shop.

Thanks,

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Paul K. Nolan, MD
The Bike Doc

 

[Brian HCM#1]

Go with the XTR 4 bolt. I have used them for the last 3 1/2 years and have no complaints. The nice thing with the XTR over the XT is the spider is replacable. So you can install a 5 bolt spider for future setups.

 

[oldfart]

The bike doc is misinformed. The 34 tooth cog on XTR cassettes is Titanium. The xt 11-34 or 12-34 is all steel. Rings for standard mountain 5 arm cranks are easy to find. Race Face, Black Spire, Envy as well as Shimano and probably a host of others are readily available from any decent bike shop. Oh yeah, my 44 year old knees have no problem with a 24-34 low. I do run a 22-34 low but its rarely used. The 32-34 on the other hand is awesome. By the way the LX crank is identical to the XT except for the finish and steel rings I think in the middle and small, or maybe just small. So go LX splined, same bb as XT and replace the rings once worn out with aluminum ones. Or ditch the steel immediately and your happenin'. Might cost more to swap rings right away though. Personally I'd go XTR. Its the benchmark all other stuff is measured by.

 

[Mark]

If your thinking of using them for anything other than cross-country then I would not advise them. I bought a set of XTR cranks, complete with bottom bracket(4 arm) for £200. Now I thought that these cranks would be the last cranks I ever needed to buy, or so the magazines led me to believe. Wrong. The XTR cranks aged about 6 years in the space of a year. The splines wore dramatically and developed substantial amounts of play in, the bottom braket busted after around 8 months and they constantly came loose. Also being a 4-arm design the chainring bolts began to look tired and one even sheared(I would try and use steel ones and not fancy aluminium ones). I believe this to be because you have the same amount of torque being transferred through 4 bolts rather than five, hence each individual bolt takes a greater load. I would look into the ISIS system, which uses splines the whole way along the BB taper(it has a one degree taper, XTR has none), as opposed to the shimano design which only utillses only about 5mm of the BB axle.
This should provide a more secure fit and hopefully be more durable. It should also stay locked in place due to the taper.

 

[gravity]

its easy for magazines and sponsored riders to go on about XTR stuff. they don't have to pay for it. for those of us who have to pay retail (or somewhere near it) XTR stuff is not worth the extra money over XT. i saw an XTR DH single chainring the other day in the bike shop, just the ring, nothing else, and it was $200! TWO HUNDRED DOLLARS FOR ONE CHAINRING!! (aussie dollars tho, about $100US). what a ripoff. same goes for their hubs and cranks. why use XTR when you can buy DT Swiss hubs which are the same weight or less, cost less, are at least as strong, disc compatible and more. and XT, truvativ and raceface provide the obvious alternatives to XTRipoff with cranks and BB. cheaper, at least as strong, maybe not as light but who cares about 40 grams (doc nolan? 40 grams is ridiculous to worry about).

my $.02