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eja_ bottecchia 02-28-14 08:45 AM

Torquing specs questions
 
I am going to remove and re-install the crank arm on my Record UT equipped bike.

The torquing specs listed by Campy for the fixing bolt (the bolt that goes inside the axle and connects the DS and NDS crank arms) read as follows:

"Tighten with a torque of 42 Nm ./. 60 Nm (372 in.lbs ./. 531 in.lbs)"

I am used to seeing torque specs given as a single value. For instance the torque specs for the cassette lock ring are simply given as 42Nm.

What does it mean when Campy uses the division sign between the two torque values? Is that a range of 42 to 60 Nm? Or is something else going on here.

Thank you in advance for your help. :D

rpenmanparker 02-28-14 09:44 AM

Interesting. From the one UT crank I have installed, I seem to remember Campy recommending the use of Loctite. I can't remember for sure, but the two torque values may be for with or without Loctite, lower with Loctite, higher without it. Kind of just guessing here, but I do remember something about the Loctite having to do with the torque value.

rpenmanparker 02-28-14 10:00 AM

BTW I suspect BTW I suspect @campag4life can answer the question authoritatively. If you PM him, let us know what he says.

Looigi 02-28-14 10:02 AM

IDK about Campy cranks but in many other applications that would indicate an acceptable range, perhaps between slots on a castellated nut or otherwise where adjustment of preload is required.

eja_ bottecchia 02-28-14 10:59 AM

Quote:

Originally Posted by rpenmanparker (Post 16535181)
BTW I suspect BTW I suspect @campag4life can answer the question authoritatively. If you PM him, let us know what he says.

Good idea!

HillRider 02-28-14 11:28 AM

Those two numbers indicate an acceptable range of torque values, i.e. above 42 Nm and below 60 Nm. Anything within this range is ok. Torque values are often specified as a range.

eja_ bottecchia 02-28-14 11:30 AM

Quote:

Originally Posted by HillRider (Post 16535527)
Those two numbers indicate an acceptable range of torque values, i.e. above 42 Nm and below 60 Nm. Anything within this range is ok. Torque values are often specified as a range.

That is what I thought; the division sign threw me for a loop, however.

eja_ bottecchia 03-04-14 02:18 PM

Here is the answer that I received from Campag4life in response to my question about torque specs:

Hi eja
All that weird ./.I believe is the conversion to alternative torque units.

In any event, don't sweat the weird Italian nomenclature. Set your torquewrench with 10mm hex allen socket to 42Nm or 31ft-lbs.
This is important.
Brace the drive side crank arm...I like to usea short stool. Do not do this on your bike stand. Puts too much stress on theframe. Mount the wheels briefly to the frame...set the bike on the ground andbend over the top tube to brace the bike. Do not use the non drive side crankarm to brace the crank against torque. Also do not hold the crank arm in youropposite hand either...a solid surface like a stool works best. I set my footon the crank arm on the stool with rag under the carbon arm. You need a solidstop for a reliable torque wrench click out at the specified torque.

Hope that helps. Campy UT cranks are terrific..

Good suggestions, good advice...thanks Campag :thumb:


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