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Discussion Starter · #5 ·
mk00 said:
why you cant leave 2 rings at M970 for example?...it needs to buy rings separately, but M970 is great I think...
Because with all those integrated cranks you can't adjust chainline!

With 2 chainrings you need to shift the rings to the middle which isn't doable with those cranksets.You need a specially designed spider which places the rings in the correct position or you need "old" style cranks with separate BB where you can change BB lenght to get the correct chainline.
Just taking out 1 ring on a integrated triple crank isn't giving you the optimum. Proper double cranks offer perfect chainline so you can use ALL gears on the cassette without having the chain too crossed (eating away the drivetrain and your precious leg-power).
 

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nikoli8 said:
Why so heavy
They've been made for the masses, rather have a slightly heavy crankset that can cope for all weights that one thats going to splinter for guys over 100 kgs/ 220 lbs.

THM have a specific target market and all sorts of warnings. They can thus supply a niche market with uber light crankset and forks.
 

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Discussion Starter · #9 ·
Another downside of XX-cranks is the custom BCD of the chainrings! Limited chainring choice, heavy and expensive...i don't like this approach!

Right now i'm trying to convince the guys from Lightning Carbon do offer a double-specific 64/104 spider for their carbon cranks. That's the most used BCD these days and you have a wide variety of lightweight rings to choose from.

Anyway - when i compare my Lightning Carbon 27/40 crankset (522g complete) with the XX crank i have a smile on my face;)
 

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Im actually tossing my options between the XX crank or the Raceface next SL at the momment. Sure the Next is lighter but the XX is dedicated for 2 ring use which is appealing. Just trying to figure out if the XX will fit, it's REAL narrow.
 

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Hand/of/Midas said:
fastest shifting rings in the world.

bar none.
If that's true then it might be worth the extra weight.

nino said:
Another downside of XX-cranks is the custom BCD of the chainrings! Limited chainring choice, heavy and expensive...i don't like this approach!

Right now i'm trying to convince the guys from Lightning Carbon do offer a double-specific 64/104 spider for their carbon cranks. That's the most used BCD these days and you have a wide variety of lightweight rings to choose from.

Anyway - when i compare my Lightning Carbon 27/40 crankset (522g complete) with the XX crank i have a smile on my face;)
But how does your Lightning crank perform in the mud and how do those custom chainrings shift?

I have another question, what about using Cannondales Hollowgram crankset with the adapter for non BB30 frames? Would it be heavy once you add the adapter?
 

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it's brand new ring/shifting tech... i'm sure SRAM/Truvativ will whittle the rings down in time... can the BB be swapped for something lighter?
 

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limba said:
If that's true then it might be worth the extra weight.

But how does your Lightning crank perform in the mud and how do those custom chainrings shift?

I have another question, what about using Cannondales Hollowgram crankset with the adapter for non BB30 frames? Would it be heavy once you add the adapter?
I would like to know this also, I am wanting to put a hollowgram on my scott genius (73mm) So what is the weight of the adapters?
 

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yamapro said:
I would like to know this also, I am wanting to put a hollowgram on my scott genius (73mm) So what is the weight of the adapters?
PM Eliflap and see if he has a weight for the whole system. I know he will have pics of the hollogram set up.

This is his picture of the THM BB:

 

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nino said:
Because with all those integrated cranks you can't adjust chainline!

With 2 chainrings you need to shift the rings to the middle which isn't doable with those cranksets.You need a specially designed spider which places the rings in the correct position or you need "old" style cranks with separate BB where you can change BB lenght to get the correct chainline.
Just taking out 1 ring on a integrated triple crank isn't giving you the optimum. Proper double cranks offer perfect chainline so you can use ALL gears on the cassette without having the chain too crossed (eating away the drivetrain and your precious leg-power).
BS depends on bike chainline second if works on three it works on two...

I use all my gears easily with an XT HT II Crankset. with the big and big ring combo too, I also could remove the 2mm spacer to move the crank further left if I wanted too...

I use big big combo on short bursts uphills that just ain't wasting any power...

Quit over thinking everything.
 

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LA CHÈVRE
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XTR's next redesign will have a double... and I'm guessing a lot of companies will embrace doubles now with wider range 10 speed cassettes from SRAM and soon Shimano. 2x10 will be mainstream, 1x10 will become what 2x9 is/was, 3 rings will be for clydesdales...

I'm not too surprised by the heavy weight. Any (real) weight on the BB30 version?
 

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Dan Gerous said:
XTR's next redesign will have a double... and I'm guessing a lot of companies will embrace doubles now with wider range 10 speed cassettes from SRAM and soon Shimano. 2x10 will be mainstream, 1x10 will become what 2x9 is/was, 3 rings will be for clydesdales...

I'm not too surprised by the heavy weight. Any (real) weight on the BB30 version?
And people looking at climbing 3000 ft at plus 12% grade, on switchbacks.
 

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LA CHÈVRE
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2 ring cranks are not that much about weight saving IMO but rather about a more efficient drivetrain. Front shifts are much slower than on the cassette and they are more risky with chainsucks, dropped chains... A double means you shift more often on the quicker, smoother and safer rear shifts, less on the front. I usually stay on the big ring, use the whole cassette and only drop on my smaller ring when the climbs are too steep, too hard, too technical... You can get a narrower q-factor too, weight loss is minimal in many cases.
 
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