[jacksonpt]

I might be getting a pretty good deal on a set of used RaceFace cranks. The only downside is that they are square taper. I can get a good, light, affordable square taper BB for them, so that's not an issue.

I'm wondering if there is any disadvantage to going with the older square taper design. If I'm going to drop $3500 on a bike, I don't want to shoot myself in the foot by going with square taper. Would I notice any difference between square taper and ISIS on the trail?

 

[Zark]

Stiffness and durability are the big ones. Square tapers eventually loosen up and deform, which almost never happens with ISIS. BB spindles are more prone to bending and breaking on square taper too.

I personally wouldn't bother with square taper unless I was easy on equipment and not doing DH/FR stuff at all.

 

[jacksonpt]

Originally posted by Zark
Stiffness and durability are the big ones.

Ah, ok... them perhaps some more info would help...

I weight about 175lbs, and they will be going on a Yeti 575 trail bike. No downhill, no freeride, but I'll ride whatever I come across on the trail.

 

[BurlyShirley]

Man,

Just get some ISIS cranks and be done with it. Those square tapers come loose one time and you dont notice, and then BAM the whole BB spindle is rounded out plus it screws up the crankarm.
Just dont take the chance. For a 3,500 bike, buy what works, not what "should be ok"

 

[binary visions]

Personally, I think square taper is a bad design. It served its purpose but your 575 is capable of far more agressive riding than a square taper BB might survive.

Square taper spindles are pretty small, the chance of stripping them is pretty good, they're more difficult to take off and put on... It just makes more sense to go ISIS, unless you were on a super tight budget or something.

ISIS has its own flaws but that's another conversation...

 

[Echo]

Originally posted by binary visions
Personally, I think square taper is a bad design.

Word. The square taper BB/crank interface is completely obsolete now. There is no benefit at all to it. I didn't even know any decent parts still came with that outdated design.

Building your 575 with a square taper BB and cranks would be a shame

 

[jacksonpt]

nuff said - ISIS it is.

Thanks guys.

 

[Jozz]

Originally posted by Echo
Word. The square taper BB/crank interface is completely obsolete now. There is no benefit at all to it. I didn't even know any decent parts still came with that outdated design.

Building your 575 with a square taper BB and cranks would be a shame

I'm still running square taper Un-72 on Raceface forged cranks on my Bullit...

Donnations accepted...

 

[Cracker]

I'll take some donations too. Been running square taper Deore cranks on my Slayer for three years now. No problems, yet lots of drops and jumps.

You just got to watch them, and be careful when removing/installing.

 

[blue]

If you're just doing XC and Trail, I don't see whats wrong with it. While there are some installation issues, if you watch them, they'll be fine. I mean, I've seen RaceFace Turbine LPs with rings going for 150 bucks online, only cause they're square taper. Why pay an extra 150 bucks for something that really isn't worth it? I mean, theres nothing wrong with splined cranks, yeah they're nice, but for trail and XC I don't see how someone can justify dropping extra cash for it if they're watching the fundage. However, if you've got the money, go for it, there are advantages to it.

 

[Wumpus]

Isis vs square taper

Little on the roady side, but interesting.

 

[Wumpus]

Another discussion

 

[JRogers]

Well, I might be in the minority here but I say that Octalink beats them both. You can get an '03 XT setup for around maybe 120 w/BB.

 

[-dustin]

i don't think square taper is inferior. if i could afford it, i'd set up my XC bike with Middleburns and a Phil bb over my RF Turbine LPs with Sig XS bb.

 

[neurostar]

Originally posted by JRogers
Well, I might be in the minority here but I say that Octalink beats them both.

But, afaik, no one besides shimano uses octalink... whereas with ISIS, a variety of companies make compatible cranks and BBs. (Of course, I've heard the compatibility isn't always perfect...)

 

[-dustin]

i think Blackspire has some Octalink stuff, too.

 

[neurostar]

Ah.
I didn't know shimano was licensing it.

 

[dlb]

I would try for the new Raceface stuff like the new Atlas, much like the XTR and XT stuff.
Then if not, I would try 04 XT, strong and light.

 

[blue]

Yes...if you have the cash, get the RaceFace Deus with the X-Type BB (Integrated like Shimanos stuff).

Also, my cranks are octalink, they're Specialized Strongarm IIs...Shimano did license it out, but I can't remember what the terms were, it was the reason ISIS was invented. It was something like you can't make any BBs, just cranks for our BBs. I can't remember...

 

[neurostar]

Ah, ok.

 

[splat]

I use the square taper on all my bikes , never had any problems.

and if square taper is so Bad , How come Campy still uses it ?

 

[JRogers]

Regardless, I've just seen way fewer problems with Octalink than ISIS regarding bearing life. Sure, more options with ISIS but I don't need 20 different ways for it to break, just one solid one that won't. XT cranks are strong, pretty light and not expensive. The rings are great too. LX cranks are just about as good and really really inexpensive for what you get. Not the lightest setup but great strength to weight ratio and durability.

 

[JRogers]

Originally posted by splat
I use the square taper on all my bikes , never had any problems.

and if square taper is so Bad , How come Campy still uses it ?

Square taper is not bad, it's that there's better options.

Campy probably doesn't use it for a couple of reasons. One being high retooling costs and development costs. I doubt they would just jump on the ISIS bandwagon if they did go splined. Also, square taper can be made lighter and European markets are generally more weight conscious and not as tech-consious as American ones.

 

[berkshire_rider]

nuff said - ISIS it is

jackssonpt: Are you building this yourself? If you want Raceface and are looking to save money, look at these:

3 Rings
Bash Guard and 2 rings
Turnbine LP

 

[dlb]

Originally posted by splat
I use the square taper on all my bikes , never had any problems.

and if square taper is so Bad , How come Campy still uses it ?

Campy is big time in road racing, I dont think that road racing has the stress that mountain biking has on a bottom bracket, and crank interfacing, spinning vs hard pedaling, and constant pounding from bumps and drops.

Anyway, its hard to find the new RF cranks, BTI still doesnt have them, so if you cant weight, the new XT is nice too, a few grams more, but probably lighter than the older RF parts.

 

[blue]

Performance has them...I was checking with my LBS last saturday about new cranks, it seems everyone is short on supply except of course Shimano...

 

[jacksonpt]

Originally posted by berkshire_rider
jackssonpt: Are you building this yourself? If you want Raceface and are looking to save money, look at these:

3 Rings
Bash Guard and 2 rings
Turnbine LP

Yea... I'm building it up myself. I'm looking for light and cheap. RaceFace or FSA are my first preference, but Truvativ or shimano would be fine as well.

I think I'm going to see if I can find anythign used.

 

[berkshire_rider]

I think I'm going to see if I can find anythign used

If you are building up a 575, spend some extra $$$ and buy new. IMO this isn't an area to try and save a few bucks, unless you get a crankset that was barely used at a kick-ass price.

 

[jacksonpt]

Originally posted by berkshire_rider
If you are building up a 575, spend some extra $$$ and buy new. IMO this isn't an area to try and save a few bucks, unless you get a crankset that was barely used at a kick-ass price.

Eh, they're cranks. I've got el-cheapo TruVatiV cranks on my bike now and they've taken everything I've thrown at them just fine. Whatever I get will perform fine... any mountain crank from FSA, RaceFace, Shimano, or Truvativ is going to be fine - I'm just looking to save some money on a lighter crankset.

 

[splat]

Originally posted by dlb
Campy is big time in road racing, I dont think that road racing has the stress that mountain biking has on a bottom bracket, and crank interfacing, spinning vs hard pedaling, and constant pounding from bumps and drops.

There I think you are wrong !

they May not get the Bumps , But as far as hard pedaling, I think you will find it will get just as much ( if not more ) but for a longer periods of time !

 

[Wumpus]

Originally posted by JRogers
Square taper is not bad, it's that there's better options.

Campy probably doesn't use it for a couple of reasons. One being high retooling costs and development costs. I doubt they would just jump on the ISIS bandwagon if they did go splined. Also, square taper can be made lighter and European markets are generally more weight conscious and not as tech-consious as American ones.

The big payoff on Campy is bearing resistance. Most ISIS internal guys are using a roller bearing to prevent the pipe from flexing at the bearing and causing a high stress and ware point. The use a ball setup to center the pipe in the cups. The drag from that bearing setup is huge.

A Campy bottom bracket compared to a Dura-Ace is over 4 times as much drag (for the ShimaNO unit) with a 170-pound rider. There is no real problem with small bearings in a bottom bracket except for drag. As the bearing size decreases the drag goes up.


http://www.campyonly.com/roadtests/2003/isis.html

 

[Westy]

Who knew the Monkey supported terrorists. A little bump should get some well needed CIA attention.

 

[Jm_]

Who knew the Monkey supported terrorists. A little bump should get some well needed CIA attention.

 

[Serial Midget]

Huh... almost forgot how fickle bike fashion is.

 

[MikeD]

Wahabis will use only square taper, in emulation of Mohammed (PBUH).

 

[johnbryanpeters]

Wahabis will use only square taper, in emulation of Mohammed (PBUH).

PSIHB?

 

[MikeD]

Beef salami only.

 

[Jm_]

Man,

Just get some ISIS cranks and be done with it. Those square tapers come loose one time and you dont notice, and then BAM the whole BB spindle is rounded out plus it screws up the crankarm.
Just dont take the chance. For a 3,500 bike, buy what works, not what "should be ok"

To be fair, ISIS does the exact same thing. ISIS makes it fit via a taper, just like "square-tapered". ISIS stands up to abuse better, but traditional ISIS doesn't leave enough room for proper sized bearings, so GXP ISIS moves them outboard and fixes this. Problem with square taper is primarily the small size of the spindle doesn't hold up to modern riding, but the bearings on most square taper BBs were not rebuildalbe, vs external BB cranksets/BBs that allow you to buy bearings off-the-shelf.