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Crank bolt torque rant

Dec. 7, 2016, 9:16 p.m.
Posts: 5
Joined: July 7, 2007

Just finished removing and remounting a set of SRAM X9 cranks and I am always annoyed by the amount of torque that is needed to remove and tighten the crank bolts.

Shimano's hand tightened pre-load and pinch bolts seems like such a better system that I am always amazed no one else uses it, or is it under patent?

/rant

So does anyone know of a 100mm fat bike crank that does not require 45+Nm of torque to mount?

Dec. 8, 2016, 9:22 a.m.
Posts: 623
Joined: Sept. 7, 2011

raceface's newer cranks use a finger tightened preload ring etc too. Ive got them in turbine flavour and they are so easy to set up.
RF has fatbike cranks with the same system:)

Dec. 8, 2016, 9:55 a.m.
Posts: 238
Joined: Nov. 25, 2009

raceface's newer cranks use a finger tightened preload ring etc too. Ive got them in turbine flavour and they are so easy to set up.
RF has fatbike cranks with the same system:)

Raceface's CINCH cranks have a finger-preload adjustment which is awesome, but still require mega-torque to tighten down the arms.

I suspect the reason Shimano is the only brand using their pinch bolt system (currently) is that they are also the only brand not doing carbon cranks. Shimano's system isn't favourable to carbon, and it would be a pain for Raceface or SRAM to do multiple axle-crankarm interfaces.

Dec. 8, 2016, 11:43 a.m.
Posts: 1006
Joined: June 26, 2012

At least you don't need a crank puller anymore.

Dec. 9, 2016, 4:16 p.m.
Posts: 8256
Joined: Nov. 21, 2002

Raceface's CINCH cranks have a finger-preload adjustment which is awesome, but still require mega-torque to tighten down the arms.

Good tip: swap out the ittle bolt on the preload ring with a larger bolt. I think ODI grip bolts fit. My preload ring used to come loose every few rides until I swapped bolts and could finally get the ring nice and tight. It still comes loose occasionally.

Also, even if your ring stays tight, the little oem bolt head can be tough to remove without stripping the head if its corroded on there a bit. So, yeah, bigger bolt head.

Anyway, back on topic…

WTB Frequency i23 rim, 650b NEW - $40

Dec. 9, 2016, 9:19 p.m.
Posts: 5731
Joined: June 24, 2003

I like the Shimano system too. Very simple. They did experiment with. Carbon Dura Ace cranks but they didn't think there was any advantage. Shimano at. One time was the largest non military user of carbon fibre stuff. Fishing rods apparently. You can do a pinch bolt with carbon. Think of of all the frames with regular seat post collars. And stems. UCI rules for road bikes still require them to weigh around 7 kilos so super light equipment is a waste of time. They add weight to the hollow bb axles as it is.

Those cinch cranks can get pretty hard to remove. Last time I pulled mine to service the I had to resort to the dead blow mallet to encourage the bolt to move. RF have changed the pre load ring to plastic from aluminum so the teeny bolt is now a teeny screw. My aluminum one came loose a few times too. Never had a Shimano crank come loose.

Debate? Bikes are made for riding not pushing.

Dec. 18, 2016, 12:17 a.m.
Posts: 0
Joined: April 14, 2011

They did experiment with. Carbon Dura Ace cranks but they didn't think there was any advantage.

actually seen some out there in the wild, so to speak (a heritage display cabinet at Sigma Sport, UK).

Shimano's HT2 system is incredibly simple, and clever. simple install, incredibly light preload and near elimination of 'flog out' common to interference / fit systems

its basically Dia Compe's "aheadset" design turned 90 degrees and with splines on axle and arm (steerer and stem) (see Bullseye, etc.)

If fitted properly (using a torque wrench to balance the 2 clamp bolts is very important) it should not cause any issues, and is super easy to work on - as a professional bike wrench its one less issue of concern when servicing bikes, compared to many other axle / crank systems.

Dec. 18, 2016, 8:58 a.m.
Posts: 1141
Joined: Dec. 16, 2008

Good tip: swap out the ittle bolt on the preload ring with a larger bolt. I think ODI grip bolts fit. My preload ring used to come loose every few rides until I swapped bolts and could finally get the ring nice and tight. It still comes loose occasionally.

Also, even if your ring stays tight, the little oem bolt head can be tough to remove without stripping the head if its corroded on there a bit. So, yeah, bigger bolt head.

Anyway, back on topic…

But the ring itself will split if you over thighten that tiny bolt. Beware.

My rant is about how lame it is that that ring is not made of metal. A $20 piece of nylon… makes sense on a $600 set of cranks…

Dec. 20, 2016, 8:52 a.m.
Posts: 5731
Joined: June 24, 2003

But the ring itself will split if you over thighten that tiny bolt. Beware.

My rant is about how lame it is that that ring is not made of metal. A $20 piece of nylon… makes sense on a $600 set of cranks…

The original ones were aluminum. Don't know why they changed to plastic. My aluminum one did comeloose a few times. I replaced it with the plastic One which h has been fine for the few months it's been on.

Debate? Bikes are made for riding not pushing.

Jan. 24, 2017, 10:18 p.m.
Posts: 623
Joined: Sept. 7, 2011

I put turbines on last year and have no problems with the preload coming loose. The little screw is only supposed to be lightly tightened but I would love an alu version ..

Jan. 29, 2017, 5:46 p.m.
Posts: 3736
Joined: Aug. 22, 2005

My FSA arms are pinch bolted with zero isuues. Not a place I want carbon parts.

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