Road Bike, Cycling Forums banner
1 - 14 of 14 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
This may sound a stupid question but I just would like peoples thoughts / procedures.
I had a Tricross comp and that had quick release spindles. The bike was stolen and replaced by a Specialized diverge (insurance company). The Diverge has thru hub bolts.
Now the stupid question:
The manual states that the bolts should be checked with a torque wrench before riding (each ride), also that it would need torquing after say a puncture repair. Does anyone actually do this or expect that it should be done. Does anyone carry a torque wrench? or is it he case that like with a quick release, just check it hasn't come obviously loose (i.e. bounce the bike) before riding.
May sound stupid but I'd appreciate feedback
 

·
Registered
Joined
·
1,010 Posts
I've never put a torque wrench on a thru-axle. I just tighten them until it feels 'snug'.

Its a good idea to put some kind of lubricant on the bolts as well. I spray boeshield T9 on mine once a month or so. A thin layer of grease works too. Anything to allow it to move freely and not bind. Just don't over do it. You don't want excess lube to find it's way onto your brake rotors/calipers.
 

·
Registered
Joined
·
3 Posts
The manual states that the bolts should be checked with a torque wrench before riding (each ride), also that it would need torquing after say a puncture repair.

sighs

I don't know what's the deal with this torque wrench obsession. These aren't car engines, for Bob's sake! They aren't parts exposed to high heat for hours and likely to explode in your face if a screw isn't tight enough.

My many-years of experience as bike mechanic will tell you that all you need to do is just to tighten crucial parts very tight, but not CRAZY tight. What bike manuals don't tell you is that aluminum is weak... especially when in contact with chromoly steel, that's the highest density in mass markets.

Other, more important point: they're saying that for a reason tho, as new bikes got newly-assembled parts, which means it's very common that anything might loosen up. Metal parts need some use and time in order to "wield" together so they hold tight for theoretically an eternity.

That's why it's also important to always put a bit of grease before re-tightening, to avoid parts getting way too stuck.

SO manual mostly is correct here. But avoid buying some expensive torque wrench.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #6 ·
sighs

I don't know what's the deal with this torque wrench obsession. These aren't car engines, for Bob's sake! They aren't parts exposed to high heat for hours and likely to explode in your face if a screw isn't tight enough.

My many-years of experience as bike mechanic will tell you that all you need to do is just to tighten crucial parts very tight, but not CRAZY tight. What bike manuals don't tell you is that aluminum is weak... especially when in contact with chromoly steel, that's the highest density in mass markets.

Other, more important point: they're saying that for a reason tho, as new bikes got newly-assembled parts, which means it's very common that anything might loosen up. Metal parts need some use and time in order to "wield" together so they hold tight for theoretically an eternity.

That's why it's also important to always put a bit of grease before re-tightening, to avoid parts getting way too stuck.

SO manual mostly is correct here. But avoid buying some expensive torque wrench.
Hi Noided. So the story behind this enquiry is that I had a bike supplied by an internet company. The bike (a gravel) came assembled and 'ready to ride' with about two hundred miles on it (including 56 on the day) (all road miles) the front bolt came undone. that obviously caused some injuries (911 fractures over 9 ribs, punctured lung and a shoulder needing a reconstruction). The response of the company was that I should check the bolts before every ride with a torque wrench. Obviously having already done 56 miles on that ride, they weren't loose on setting off.
 

·
Registered
Joined
·
131 Posts
Get bolts with handles. You can readily see if they looked like they've loosened. Ive never had a thru axle loosen up, i just make sure they are good and tight when installing. I never use a torque wrench.
 

·
Registered
Joined
·
23,364 Posts

·
Registered
Joined
·
23,364 Posts
I don't know what's the deal with this torque wrench obsession. These aren't car engines, for Bob's sake! They aren't parts exposed to high heat for hours and likely to explode in your face if a screw isn't tight enough.
You don't torque things because of high heat and explosions. Torque is to apply appropriate force to the bolts to prevent them from coming loose. Especially if vibration is involved. Like... on a bicycle. (Kinda important for your wheels... handlebars. )

My many-years of experience as bike mechanic will tell you that all you need to do is just to tighten crucial parts very tight, but not CRAZY tight.
Not everyone has many years of experience. Which is why manufacturers give torque values. "tighten crucial parts very tight, but not CRAZY tight." is horrible advice. That could be different to anyone with a wrench in their hand.


What bike manuals don't tell you is that aluminum is weak... especially when in contact with chromoly steel, that's the highest density in mass markets.
This is all wrong and makes zero sense.

Metal parts need some use and time in order to "wield" together so they hold tight for theoretically an eternity.
No. Absolutely wrong. I've been an engineer for 30yrs. Never once have I ever heard of anything remotely close to this.
Did you mean "weld"? Because 'wield' means to "hold something". Which makes it even more nonsensical.
Whatever... metal parts don't need 'time' to hold together.


And no I don't use a torque wrench on my bikes. But it's a good idea for anyone without experience wrenching to have one. You don't need an expensive one.
 

·
Registered
Joined
·
5,863 Posts
You don't torque things because of high heat and explosions. Torque is to apply appropriate force to the bolts to prevent them from coming loose. Especially if vibration is involved. Like... on a bicycle. (Kinda important for your wheels... handlebars. )

Not everyone has many years of experience. Which is why manufacturers give torque values. "tighten crucial parts very tight, but not CRAZY tight." is horrible advice. That could be different to anyone with a wrench in their hand.


This is all wrong and makes zero sense.

No. Absolutely wrong. I've been an engineer for 30yrs. Never once have I ever heard of anything remotely close to this.
Did you mean "weld"? Because 'wield' means to "hold something". Which makes it even more nonsensical.
Whatever... metal parts don't need 'time' to hold together.


And no I don't use a torque wrench on my bikes. But it's a good idea for anyone without experience wrenching to have one. You don't need an expensive one.
I always use one for CF to CF like my aero seatpost on my Scott. It’s my fear of damaging the the frame or seatpost... I bought a wrench with the toque specified so I don’t have to even think, it’s my seatpost wrench.


Sent from my iPad using Tapatalk
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #12 ·
What manual are you looking at? The Diverge manual on the website doesn't even give a torque for the axle bolts.

Thanks Tig .... that made me take another look at the documents that I have and you are correct, it doesn't say that.
When I reported what had happened to the Company that sold me the bike, I believe that was what was quoted. Looking at it now, I guess that I just read that into it ('connected the dots' and drew something else).
The leaflet from that Company says "Check that the wheels are secure and there is no play", then checking the manual, it says in the mechanical safety check that the wheels should be tightened using a torque wrench. Guess i connected the two and believed what I'd been told.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #13 ·
Thanks Tig .... that made me take another look at the documents that I have and you are correct, it doesn't say that.
When I reported what had happened to the Company that sold me the bike, I believe that was what was quoted. Looking at it now, I guess that I just read that into it ('connected the dots' and drew something else).
The leaflet from that Company says "Check that the wheels are secure and there is no play", then checking the manual, it says in the mechanical safety check that the wheels should be tightened using a torque wrench. Guess i connected the two and believed what I'd been told.
But it does give a torque setting (in the paper manual at least), on page 52. Front 11.9 rear 15.0 N*m
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #14 ·

Attachments

1 - 14 of 14 Posts
Top