Torque Wrench Carbon Frame / Forks

Chris65

How essintial is a torque wrench for carbon forks and frames? I know the manufactures will say components must be fitted with the correct torque and this is probably true with bottom brackets etc.

What I want to do is change brake calipers which on a non carbon frame is simple but I am put off on my new carbon frames.in case I overtighten the bolts.

Should I need a torque wrench any idea what range this should cover? Park do a nice one (if rather expensive) which works between 3 & 15 mN. Will that cove the bike range

Next question - where is the best place to find the correct torque setting to use?

Your adice please

Stone Glider

Those wonderful people at Screwfix do a wrench which covers 5 to 25Nm for about thirty quids.

itboffin

I'd say yes, I didn't use one until I finally splashed out on carbon, then having spent so much on what is effectively plastic the last thing I wanted to do was break it, i'm very heavy handed serial over tightener.

£50 seemed a small price to pay, I have since checked every nut and bolt on my other bikes and sure enough everyone was massively to tight.

http://www.ribblecycles.co.uk/sp/road-t ... 0000000000

furrag

Santa got me the BBB Torquefix tool in the link above this year.

I have just finished building a Cervelo Soloist this week and wanted to torque everything up - especially with the carbon seatpost. I nipped downstairs and undone the glittery paper as meticulously as it was wrapped up. It's very easy to use and gives a solid 'clunk' when torque is achieved. I'm surprised a headsets top caps being so low in torque - no wonder I've sheered a couple off. :roll: I'd definitely recommend it. I was very sad to wrap it back up again, especially when I had to adjust my seat posts height while out on its maiden ride today. :roll:

desweller

Furrag wrote:

I'm surprised a headsets top caps being so low in torque - no wonder I've sheered a couple off. :roll:

Holy Jesus - you do know that's only there to take up play in the bearing right? It should only be tight enough to stop the steerer from slopping about - if you overload it you'll destroy the bearing surfaces.

itboffin

Remember folks to always unwind your torque wrench after use.

nicklouse

a question would you be concerned if you were fitting the brakes to another non carbon frame?

As the brakes are only threaded onto themselves and the joining point on the frame and fork are solid and strong and also as they are not threaded there is no torque figures there.
the Torque figure is the same whatever the brakes are fitted to.

But yes they are a good investment.

Furrag
err there are no torque settings for top caps. the top cap does not even need to be present after the stem has been fitted and tightened. in fact some road bikes dont even have top caps fitted with some of these new headsets.

tri-sexual

recommended torque for shimano caliper fixing bolt to frame: min 8Nm, max 10Nm
campagnolo caliper fixing to frame: no min torque given, max 10Nm
both are for side pull brakes, for other brakes types/ makes i can give you these also, let me know.
caliper fixings to certain bikes (on carbon seat stays), the recommended torque settings are a little lower:min 6Nm, max 7Nm.

furrag

DesWeller wrote:

Furrag wrote:

I'm surprised a headsets top caps being so low in torque - no wonder I've sheered a couple off. :roll:

Holy Jesus - you do know that's only there to take up play in the bearing right? It should only be tight enough to stop the steerer from slopping about - if you overload it you'll destroy the bearing surfaces.

Yup - soon found that out on a literature search. I had play in the headset at the time, and with hindsight, it was owing to being a mm too short in spacing. Of course, I was following guides on loose headsets which were pretty ambiguous in their "now tighten the headset" claims. Only when I searched on forums did I see suggested torques of 1-2nm, which when tightened with the torque wrench, was met with big rolling eyes.

Chris65

There are two bike involved. I want to swap over the calipers.

The first is a Cannondale supersix carbon with Cannondale fork currently has tektro brakes. The other is a Trek with a Botrager carbon crown & fork. This has Tiagra brakes (the reach is not as long as the Tektro)

Any torqu setting would be much appreciated. Even better a source for torque settings

tri-sexual

tektro brakes have recommended torque of 8Nm min, 10Nm max
the same is true for your shimanos
on your trek, rear brake should be 6Nm min, 7 Nm max if it is carbon with a seatstay mounting, like the madones. if not then 8Nm min, 10Nm max
i use torque charts covering most manufacturers
commercially torque charts can be found in zinn books, blue book has some recommendations.
manufacturers web sites are well worth checking out, they often provide invaluable information and best of all they tend to be up to date and free.

dennisn

Just to play devils advocate, and post my own view, I say that torque wrenches for bicycles are a solution to a problem that doesn't exist. It's all a load of crap from manufactureres who simply want to sell you more stuff. I sort of compare them to those chain cleaning things, another solution to a problem....... Bikes simply aren't that technical.

Monty Dog

Dennis, as you admit yourself, you ride a steel frame and don't possess anything made from carbon fibre. To anyone whose experienced the 'crunch' of failing carbon due to over-tightening, then the torque wrench is the solution - these parts were not designed to be over-stressed and if you don't know how 'tight' tight is, what alternative is there? That said, fork steerers are generally solid and therefore have never needed to use a torque wrench to tighten a brake caliper bolt - yet.

dennisn

Monty Dog wrote:

Dennis, as you admit yourself, you ride a steel frame and don't possess anything made from carbon fibre. To anyone whose experienced the 'crunch' of failing carbon due to over-tightening, then the torque wrench is the solution - these parts were not designed to be over-stressed and if you don't know how 'tight' tight is, what alternative is there? That said, fork steerers are generally solid and therefore have never needed to use a torque wrench to tighten a brake caliper bolt - yet.

This all goes back to my original question in some long forgotten post. How can people have any faith in something that goes "crunch", as you say? I guess I don't believe that these carbon parts are as fragile as the are often made out to be. I can understand why tool manufacturers would want you to think that these things are fragile - to sell you a tool to protect it. I have even seen advert's, for torque wrenches, that include the words "fragile carbon....". I have heard of seatpost failures but little else. I guess that maybe I've sort of been sucked into kind of believing that carbon is not safe(for lack of better words) and therefore don't have any on my bike, but I think that the main reason I don't have any is that I don't see any advantage to paying the extra cost for it. It's also part personal preference, in that I don't really care for the look of most carbon frames.
So here I sit with a lugged steel, chromed fork Gios because I like it and not because I have any fear of carbon. I can't imagine carbon being as fragile and needing as much care as some would have you believe.

flasher

dennisn wrote:

Just to play devils advocate, and post my own view, I say that torque wrenches for bicycles are a solution to a problem that doesn't exist. It's all a load of crap from manufactureres who simply want to sell you more stuff. I sort of compare them to those chain cleaning things, another solution to a problem....... Bikes simply aren't that technical.

But bike manufacturers don't make torque wrenches, so have nothing to gain. In fact the opposite would be true, it would be in the manufacturers interest for home mechanics to be over-tightening their bikes up hoping to sell more parts/frames etc.

Monty Dog

I guess Dennis has go a workshop full of twisted engine cylinder heads too?

dennisn

Flasher wrote:

dennisn wrote:

Just to play devils advocate, and post my own view, I say that torque wrenches for bicycles are a solution to a problem that doesn't exist. It's all a load of crap from manufactureres who simply want to sell you more stuff. I sort of compare them to those chain cleaning things, another solution to a problem....... Bikes simply aren't that technical.

But bike manufacturers don't make torque wrenches, so have nothing to gain. In fact the opposite would be true, it would be in the manufacturers interest for home mechanics to be over-tightening their bikes up hoping to sell more parts/frames etc.

I meant it to mean tool manufacturers want you to buy more tools. Of course, I'm sure frame and component makers secretly love the guys who use hammers and breaker bars
on allen wrenches to tighten seat bolt clamps, stems, and things like that. I'm just one of those skeptic's who doesn't believe that just because someone makes something and tells you that you need it that it means you must have it. But that's just me. I'm sure I go a bit overboard, in my thinking, on things like that.

rolf_f

dennisn wrote:

Just to play devils advocate, and post my own view, I say that torque wrenches for bicycles are a solution to a problem that doesn't exist. It's all a load of crap from manufactureres who simply want to sell you more stuff. I sort of compare them to those chain cleaning things, another solution to a problem....... Bikes simply aren't that technical.

What, those chain cleaning things that mean it only takes seconds to clean your chain and discover how much more sweetly it runs rather than just looking at the black gunky thing and think 'I'm sure that goo isn't doing any harm even though the chain hardly bends anymore'!? I suspect the weather in Ohio isn't nearly as dank as it is in Yorkshire

I know I wouldn't clean my chain half as often without one and I know that the chain does run more smoothly after having been cleaned. So what problem am I having that doesn't exist?

Obviously, I also own a BBB torque wrench and very nice it is too! Apparently people always over-tighten small bolts and undertighten the big ones. If you can afford a carbon bike, why on earth wouldn't you invest a little extra for piece of mind?

dennisn

Rolf F wrote:

dennisn wrote:

Just to play devils advocate, and post my own view, I say that torque wrenches for bicycles are a solution to a problem that doesn't exist. It's all a load of crap from manufactureres who simply want to sell you more stuff. I sort of compare them to those chain cleaning things, another solution to a problem....... Bikes simply aren't that technical.

What, those chain cleaning things that mean it only takes seconds to clean your chain and discover how much more sweetly it runs rather than just looking at the black gunky thing and think 'I'm sure that goo isn't doing any harm even though the chain hardly bends anymore'!? I suspect the weather in Ohio isn't nearly as dank as it is in Yorkshire

I know I wouldn't clean my chain half as often without one and I know that the chain does run more smoothly after having been cleaned. So what problem am I having that doesn't exist?

Obviously, I also own a BBB torque wrench and very nice it is too! Apparently people always over-tighten small bolts and undertighten the big ones. If you can afford a carbon bike, why on earth wouldn't you invest a little extra for piece of mind?

As to the weather in Ohio, well, just be glad you're over there and not here 10 degrees F.
was the high today and the roads are snow covered. In any case I'm way to old to subject myself to riding in unpleasant weather, so your chain cleaning may, of necessity, be a bit more thorough than my clean rag , once every 3 or 4 days, wipe down, and relube. It's possible that I may have been sucked into believing that the lubes really are self cleaning. So why would I need a chain cleaner?
As to the torque wrench, I was just being a voice for the other side, although I have never had reason to feel I needed one(for a bicycle), even if I did have carbon parts.
I guess I sort of wonder why, and how, carbon got this reputation as a "fragile"(for lack of a better word) material. Carbon stuff is more a money thing with me than it is being a product I don't have faith in.

giant_man

Carbon isn't that fragile Dennis, it's quite strong and resilient really, you don't own a carbon bike presumably.

dennisn

giant mancp wrote:

Carbon isn't that fragile Dennis, it's quite strong and resilient really, you don't own a carbon bike presumably.

I don't have any issues with carbon. Like I've asked before "How did it get it's fragile
reputation?". At least that seems to be the consensus on this forum, what with people always asking whether a simple little scratch has ruined their bike(or someting like that).
For me it's more of a price thing. Why pay a bunch more for something that doesn't really
do any more than it's metal counterpart(stems, bars, seatposts, cranksets, frames, wheels)?

chill123

worth the investment in my opinion.

i use a shimano pro:
http://www.bicyclecenturytraining.com/b ... -wrenches/

rolf_f

dennisn wrote:

In any case I'm way to old to subject myself to riding in unpleasant weather, so your chain cleaning may, of necessity, be a bit more thorough than my clean rag , once every 3 or 4 days, wipe down, and relube. It's possible that I may have been sucked into believing that the lubes really are self cleaning. So why would I need a chain cleaner?
As to the torque wrench, I was just being a voice for the other side, although I have never had reason to feel I needed one(for a bicycle), even if I did have carbon parts.
I guess I sort of wonder why, and how, carbon got this reputation as a "fragile"(for lack of a better word) material. Carbon stuff is more a money thing with me than it is being a product I don't have faith in.

Ah well, that says something! Out almost every day, whatever the weather. Cleaned the bikes all nicely this weekend, now both covered in cack. Chain cleaners are a godsend!

As for the torque wrench - I suspect the margin between tight enough and damaged frame is narrower on a carbon bike. And I just don't have a feel for how far I should go with carbon. Somehow, with steel I feel I do. Might be wrong but, for a tiddly investment compared to the frame cost, Im happier going with all those little torque settings wrtitten on all the components!

dennisn

Rolf F wrote:

dennisn wrote:

In any case I'm way to old to subject myself to riding in unpleasant weather, so your chain cleaning may, of necessity, be a bit more thorough than my clean rag , once every 3 or 4 days, wipe down, and relube. It's possible that I may have been sucked into believing that the lubes really are self cleaning. So why would I need a chain cleaner?
As to the torque wrench, I was just being a voice for the other side, although I have never had reason to feel I needed one(for a bicycle), even if I did have carbon parts.
I guess I sort of wonder why, and how, carbon got this reputation as a "fragile"(for lack of a better word) material. Carbon stuff is more a money thing with me than it is being a product I don't have faith in.

Ah well, that says something! Out almost every day, whatever the weather. Cleaned the bikes all nicely this weekend, now both covered in cack. Chain cleaners are a godsend!

As for the torque wrench - I suspect the margin between tight enough and damaged frame is narrower on a carbon bike. And I just don't have a feel for how far I should go with carbon. Somehow, with steel I feel I do. Might be wrong but, for a tiddly investment compared to the frame cost, Im happier going with all those little torque settings wrtitten on all the components!

Fair enough. I'm just sort of covering the other side of the story. You know, being argumentitive just for the "why not" of it.

vorsprung

I recently bought a Carbon Fibre framed bike

I see where dennisn is coming from. Basically, the point is if carbon fibre is so delicate that it can be cracked by over tightening with a spanner then why make bikes from it? From this inference it could be concluded that carbon fibre isn't for the real world where bolts are over tightened and knocks and thumps "just happen"

There's two counter arguments to this. Firstly, carbon fibre as a material is directional. It holds its strength in particular directions. This might be true to some extent of other materials too. For example a steel tube could be crushed by a weight or force that it could quite happily bare. Carbon fibre seems much more prone to this sort of specific strength in a particular direction. This is an advantage as you can make a bike that bends one way but is stiff the other. Most CF bikes have a good stiff bottom bracket area and can transmit power well but have a certain amount of flexibility in the rear triangle to absorb road noise.
In the context of tightening a bolt to hold a stem onto a carbon fork it is possible to see how a fork could be extremely strong at holding the wheel with the weight of the rider but be crushable with a force which is completely orthogonal to the usual ones it has to cope with.

Secondly, tightening by hand is a great method. In a sense the person doing the tightening is the torque meter. But there is always a chance that too much enthusiasm could be used and so too much force. I have broken steel bolts this way, it is not limited to carbon fibre. Using a torque wrench is a simple way to regulate this activity

I decided to just get a torque wrench that would do the stem and seat clamp. These seemed to be relatively low torque limits but damage from over tightening could be expensive and / or dangerous
I got a cheap Ritchey Torque Key which is ideal for this application, easy to use and portable too.

geebee2

One way with the seat post clamp is to get a very light weight clamp, then if anything breaks it will be the clamp ( which is quite cheap/easy to replace ... ).

With carbon assembly paste, I have found that the clamp bolt does not need to be very tight at all.

I use my little finger (only) to tighten it with a normal (~10cm) long 3mm allen key.
Something like 2-3Nm.

My clamp is one of these:
http://www.chainreactioncycles.com/Mode ... elID=38648

navrig

I found this document when searching for info on bike torque settings:

http://www.parktool.com/uploads/files/blog/torque.pdf

tri-sexual

its not just carbon, steel, Ti, ali can all be overtightened.
overtightened parts can result in stripped threads and crushed components.
there have even been reports (some quite recently) where avaition service technicians failed to correctly fit aircraft parts which resulted in accidents which took over 100 lives.
no carbon fibre was involved, just poor worksmanship and negligence.

rake

just proves you get dick heads working on planes too.
for a lot of people whove done things like snap bolts, torque wrenches are a must. not everyones like that though. i verified my own methods and estimation recently which people would lead me to believe would be way off the mark. ive got a ritchey torqkey now, and tested it against how id set my bike up by hand for the past year with no problems and nothing slipping or coming undone, and as i expected the face plate and steerer bolts tightened significantly further before the torqkey clicked out at 5nm. im also not going as tight as 5nm on any of those bolts, its not necessary with assembly paste.