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2007 Vett
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Hi

Does any know what the torque value is for the 5mm blot that goes into the headset. I just replaced the stem on my Roubaix Expert and can't find the torque value for that bolt. Knowing it goes into CF, I want to be real careful.

Thanks
Chuck
 

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Cycling induced anoesis
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scooterpilot said:
Hi

Does any know what the torque value is for the 5mm blot that goes into the headset. I just replaced the stem on my Roubaix Expert and can't find the torque value for that bolt. Knowing it goes into CF, I want to be real careful.

Thanks
Chuck
I've never seen torque values published for this adjustment, it's done more by feel. Here is an outline of the process that may help guide you.

1. With the front wheel installed and QR tightened, adjust your stem bolts so that they are just barely snug on the steerer tube. You should be able to move it side to side without the fork turning too (by holding the wheel). This is important, as you want to be able to pull the steerer tube up through the stem in the next step, and if too tight, that wont happen.
2. Tighten the top cap while you turn the fork side to side (straddle the front wheel), or if on a stand turn it with your hand. (Dont use the stem to do this)
3. Continue tightening until you JUST start to feel the fork ticking (binding) as you turn it. This is subtle and you may want someone to show you the first time.
4. Back off the cap nut about 1/8th of a full turn. You should no longer feel the subtle binding when turning the fork. (steps 3 and 4 may take a couple of tries)
5. Align your stem and torque down the stem bolts on the steerer tube.
6. Check your work: Place the bike on the ground and holding the front brake tight, rock the bike back and forth on the front wheel. You SHOULD NOT FEEL ANY PLAY WHATSOEVER. Next turn the bars from side to side, YOU SHOULD NOT FEEL ANY BINDING WHATSOEVER.
 

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PJ - any guidance on the torque for the stem itself? My new love is my Tarmac SL2 which has a max. torque of 40 ft lbs or 4.5 nm - my LBS said that I could simply snug it up and w/b fine. I also see that Ritchey has a 5 nm torque key for about $20 which is just over the max. recommended. LBS that w/b fine too...
 

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Cycling induced anoesis
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I-Ride said:
PJ - any guidance on the torque for the stem itself? My new love is my Tarmac SL2 which has a max. torque of 40 ft lbs or 4.5 nm - my LBS said that I could simply snug it up and w/b fine. I also see that Ritchey has a 5 nm torque key for about $20 which is just over the max. recommended. LBS that w/b fine too...
The textbook answer is to suggest you get a torque wrench (Sears, for maybe $25) and a set of keys, especially if you plan on doing most of your own wrenching. In the long run, they'll pay for themselves many times over. But I've been working on bikes since the 80's so I do everything by feel. Tighten both bolts evenly until you have about a 1 mm space between stem clamps. Go slow and don't overdo and you'll be fine.
 

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At this point I am really only planning on doing things like flipping the stem or adjusting handlebars,...futzing with the seat post. I looked at a beam style torque wrench at Sears (you are spot on regarding cost....$25, not a big deal), but the scale on it was such a big range that for a 40 ft. lb. torque, then centered needle would barely move.... and thus seemed like very little pressure was needed.

Nashbar has a torque set for $75 that is not a beam style but ratchet style. Any opinion on whether the Nashbar product would be okay? Similar tools from Sears are well over that price, so I am a bit skeptical on quality. The last thing I'd want to do is use a torque wrench that is not properly calibrated and overtighten (and ruin) my wonderful bike!
 

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Cycling induced anoesis
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I-Ride said:
At this point I am really only planning on doing things like flipping the stem or adjusting handlebars,...futzing with the seat post. I looked at a beam style torque wrench at Sears (you are spot on regarding cost....$25, not a big deal), but the scale on it was such a big range that for a 40 ft. lb. torque, then centered needle would barely move.... and thus seemed like very little pressure was needed.

Nashbar has a torque set for $75 that is not a beam style but ratchet style. Any opinion on whether the Nashbar product would be okay? Similar tools from Sears are well over that price, so I am a bit skeptical on quality. The last thing I'd want to do is use a torque wrench that is not properly calibrated and overtighten (and ruin) my wonderful bike!
For the type of wrenching you're thinking of doing I think tightening until snug is going to work for you. Error on the side of tight enough, rather than too tight. With or without a torque wrench you'll always test your work, as in trying to move the bars or seat after tightening.

I did a quick search here just to see what I came up with, and predictably there's been a lot of discussion on the topic. Check the link below for more info. Also, if you want even more info, just type torque values in the search field and you'll be inundated with members input.

Hope this helps!!

http://forums.roadbikereview.com/showthread.php?t=118575&highlight=torque+values
 

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the problem with the Ritchey thing is that not all are maxed at 5Nm. I know this because I cracked a carbon bar (stem was rated at 5.5Nm) using one. i compared it to another one and they were off a fair bit. i've never cracked, nor under-tightened, a bar or seatpost using the torque wrench in my wrist, so i went back to that.
 

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Which torque wrench are you using?

Hand tightening w/o it seems like it might not be the wisest.....I'd hate to undertighten and find myself diving into a turn or jumping to sprint and end up with the steerer tube slipping off center....

Not to belabor the point, but wouldn't it be best if ANY torque wrench for bikes came with NM readings!
 

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Just wanted to point something out about your stem torque values. It should be 40 in-lbf for 4.5nm

40ft-lbf is = to roughly 54nm. Ouch.


Quick conversion chart.

NM x 8.850 = inch pounds

Nm x 0.7375 = foot pounds
 

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Details, details, details.

Actually I guess I did know that - it's on the stem itself, but I do appreciate the clarification to the post.

And that really is the reason I've decided for stem adjustments to use a Park hex tool instead of a torque wrench b/c the torque required is so low. I had picked up a Sears Torque wrench that had a range of 0 to 75 ft. lbs. To use it, the needle barely moved off center, and it didn't seem very useful.
 

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The Park TW-1 works well and is calibrated in a much better range for stems, seatpost collars, and most small fasteners on the bike, (0-60 in-lbf).

The prices isn't bad if you shop around some, and it works well.

Crap, it's nice out for once, I need to go ride.
Cheers.
 
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