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That claims to be compatible with select 30mm spindle cranks (essentially those with spindles long enough to span the setup... so not strict BB30 cranks, but ones like Rotor 3D+, or the new Race Face Next SL... not listed, but I'd bet the farm it would work)
Anyway, sometimes one has to stick one's neck out a little bit in order to make progress. In your case, I don't think you have to stick it out very far: order the Beer components BB, and don't even install it, but measure the cup thickness accurately, and measure your frame's BB shell (almost certainly 73mm +/-) and then you can infer what will be the outside-to-outside measurement with BB installed. For the Race Face Next SL cinch crank to work, the outside-to-outside measurement must be 98.1mm +/- 1mm (see http://www.raceface.com/comp/inst/B1018 ... lation.pdf ) ... so if your measurement is 99.1mm or less, you can make it work (note that if the measurement is less than 97.1mm then you just need to add spacers to the spindle, outboard of the bb cups... until you get up to the needed width; you can get such spacers out of delrin at most bike shops because they're used for a lot of BB30/PF30 cranks eg Hollowgrams... (Guessing based on the RF directions that you'd want to add the spacers to the drive side first, since there is normally a 2.5mm spacer on that side that you won't have).
Worst that can happen is that you have to return the Beer components BB (not a problem since you won't have installed it). It's not my money, but like I said... I'm VERY confident it will work based on the other cranks they state compatibility with.
2wheeltyson wrote:I'm stuck with 24mm because I'm using a Problem solvers eccentric BB to make my PF30 frame a single speed...Unless there's another option I've missed? My current cranks are xtr m960 that I cut the spiders off, they weigh 496g but a custom 29t granny gear is the biggest available and I'd like to go larger.
As long as you have enough stay/ring clearance for something bigger, why not get a custom ring? Fibre-Lyte, Experimental Prototype, Cycle Underground and probably some others could make something to suit... It should still end up cheaper than new cranks/ring unless you find a bargain.
Don't think I've seen a 64mm BCD only conversion before, do you have a picture? Modded M960's are cooool and pretty good weight wise.
Otherwise, another option for a replacement could be a GXP shim kit, SRAM crank and spiderless ring with your existing BB.
A really cheap, easy option would be SLX cranks and a light, single ring. The arm-only weight is almost identical to XT and they can often be had very cheaply. Extralite seem to have the lightest 'stock' single rings around.
I guess I don't see continuing with a 24mm spindle to be achieving much. Yes, the OP could get a larger chainring than he has now, but he's not going to save any weight, and may well add it. A Sram carbon crank with direct-mount chainring is going to weigh around 550g... which is a 50g increase on what the OP has now. Cost-wise it'd be around $350 which isn't chump change either. Shimano options also aren't going to come out any lighter, and I feel like if the OP is going to spend money, he ought to get something better (offer bigger ring, but also be lighter) than what he has now. Plus the nice thing about the RF option is that if he wants to move the crank to another bike... there are almost unlimited options for how the crank can be used (can be converted to a double, triple, etc... and used with almost any BB type). That makes it a smart/safe investment if you ask me.
A custom ring could weigh less than what they're already running now.
The RRP on the NextSL is a lot, on par with SiSL depending on the setup... only things like the Tune Blackfoot/THM etc and PM cranks cost more. The NextSL would also require a new BB as well, further increasing the cost. No harm in just mentioning a few cheaper options that would use the current BB and still give the OP what they're after.
dwaharvey wrote:Given your stated desire for 24mm spindle... no option is going to be much lighter than another, or very light for that matter. Why does it have to be a 24mm spindle? Assuming you're saying this only because your bike has a BB92 bottom bracket (not because you are married to the idea of a 24mm spindle, and because I can't think of another good reason to stipulate this), I think you should strongly consider the new RaceFace Next SL with 30mm spindle. Their BB92 bottom bracket has the same size ball bearings as you'd find on a standard BB for 24mm spindle cranks, and more balls at that. And the crank is a great design: I just installed one last week and rode it today... nothing but good things to say about it, and it's design. And weight-wise it's about 150g lighter than eg SRAM XX1 let alone X01
Can you explain me how is it possible? Assuming we're talking about a pressfit BB92 frame which is has BB shell that measures 41mm. If we take out the 30mm necessary for the spindle we have left 11mm which have to be split in 2 (as it is a circumference). Then you have 5.5mm where you have to put a BB and a bearing. Unless the bearings were outside the frame (which they cannot be because there is no axle width) it is impossible to have a bearing with the same size as you would find on a regular 24mm spindle!
I had this issue when i was deciding which crankset to use on my new mtb and decided to use the XX1 because i was tired of the bearing issues with the Clavicula (30mm spindle) with those crappy size bearings necessary to fit it on a PFBB92 frame.
@damond: Do a google search about it... you'll find that they achieved it by eliminating the cups that are normally used to house BB92 bearings; instead the outer race of the bearing has the shape of the cup (with lip to control insertion depth). The claim is merely that the balls within the bearing are the same size as the balls within a standard BB bearing for 24mm spindle (but the increased ID from 24->30mm means there are more balls in the RF bb).
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