Spoke Torque Question....

[CaptainBob]

I have a 2023 GG 300TXT.  The manual says spoke torque is 26 inch pounds for rear and 18 inch pounds for front.  Most dirt bikes and other bikes I have owned are spec'd between 40 and 50 inch pounds  I checked the spokes yesterday on my GG and they are much tighter then what the book called for.  Am I misunderstanding something?  Any and all thoughts are appreciated.

[lemur]

Wet or dry? ... hit one of the old spokes with penetrating oil first, might make a huge difference in the readings.

[konrad]

A bike that new should not need this trick, but in addition to lemur's penetrating oil, particularly nasty ones need heat.  I generally give the nipple a quick blast with a propane torch.   I always make sure I can loosen a nipple prior to attempting tightening.

You can tell a lot just by sound.  Try tapping each spoke with a light tool (screwdriver, spoke wrench, etc.).  Tight spokes will ring.  Loose ones with thud.  You want them all to sound similar.  I don't own a spoke torque wrench.

 

 

[CaptainBob]

On 7/1/2024 at 11:23 AM, lemur said:

Wet or dry? ... hit one of the old spokes with penetrating oil first, might make a huge difference in the readings.

I hear what you are saying but this is a new bike.  Nipples shouldn't be frozen yet.  I have done the tap technique but wanted to be a bit more precise so figured I would use my torque wrench.  Any thoughts on what seems to be really low torque specs?

[CaptainBob]

23 hours ago, konrad said:

A bike that new should not need this trick, but in addition to lemur's penetrating oil, particularly nasty ones need heat.  I generally give the nipple a quick blast with a propane torch.   I always make sure I can loosen a nipple prior to attempting tightening.

You can tell a lot just by sound.  Try tapping each spoke with a light tool (screwdriver, spoke wrench, etc.).  Tight spokes will ring.  Loose ones with thud.  You want them all to sound similar.  I don't own a spoke torque wrench.

 

 

I like that heat technique.  I will use it next time I get a frozen spoke nipple.

[CaptainBob]

Does anyone actually measure the torque on their spokes?  I am surprised I have not heard from anyone about the, what seem to be, really low torque specs published by GG.

[konrad]

I assume they are Morad rims.  You could try to contact them directly https://www.moradsa.com/ and ask for torque specs.

[b40rt]

8 hours ago, CaptainBob said:

Does anyone actually measure the torque on their spokes?  I am surprised I have not heard from anyone about the, what seem to be, really low torque specs published by GG.

No 😎

[ChrisCH]

Many many years ago I did a wheelbuilding course for MTB wheels.  The guy who taught me said he had investigated motorbike wheels but they never needed rebuilding and there was no money to be made.  Since then virtually all cycle wheels are now machine built and are so good off the production line they need no attention.  My spoke keys are untouched for the last decade.

A quick internet search suggest that there is an issue with KTM wheels but that is about it.  (I have two friends with KTM enduro bikes but never heard any feedback).  The MTB course taught to "tune" the spokes by ear and the tighter the better.  No torque settings were ever mentioned.  (I had to google the torque wrench - never seen one).  The big issue with cycle wheels was alloy nipples which broke as they were not strong enough.  Traditional brass nipples were trouble free.

As part of the course you built a wheel - bring your own components and make a wheel for yourself.  I built a back wheel for the missus Orange and the build outlasted the hub (Hope).  I do remember the instruction "the tighter the better".  I would - based on my experience - therefore not worry about spokes being "too tight".

[konrad]

I considered buying a spoke torque wrench when building some supermoto wheels a decade ago but decided it was unnecessary.  

Although torquing may make sense for brand-new spokes, by the time the threads see any mud, water or just dirt, tightening torque no longer has much relationship to tension.  And proper tension is the thing you are trying to achieve.  Tension does have a relationship to the sound the spoke makes when you hit it.

Ducati even decided that sound was the best indicator of cam belt tension.

[lemur]

You can also determine max torque values by knowing only the material used in the nut & bolt and the size of the threads, there are charts based only on that information.  Maximum torque will typically be something prior to elongating the bolt or spoke unless the bolt is designed for single use like in some cylinder head bolts, this is not the case for spokes and barring physical impact damage we hope they last the life of the machine.

There is a lot more flex and movement in a spoked rim then most might think, watching a pro riders rear rim impact a rock face during a big splat will reveal just how much deformation can occur and how far a rim can spring back to being round again is fairly amazing to watch.

[CaptainBob]

I have built wheels for dirt bikes (motocross) and have used both methods (tap/sound and torque wrench)..  I guess I assumed others have used torque specs as well.  Apparently, GG thought it was important enough to publish the torque spec in their manual although, I think their spec is a bit off the mark.  Maybe something got lost in translation.  lol   Certainly not a big deal.  Thanks for all the responses!

[CaptainBob]

1 hour ago, lemur said:

You can also determine max torque values by knowing only the material used in the nut & bolt and the size of the threads, there are charts based only on that information.  Maximum torque will typically be something prior to elongating the bolt or spoke unless the bolt is designed for single use like in some cylinder head bolts, this is not the case for spokes and barring physical impact damage we hope they last the life of the machine.

There is a lot more flex and movement in a spoked rim then most might think, watching a pro riders rear rim impact a rock face during a big splat will reveal just how much deformation can occur and how far a rim can spring back to being round again is fairly amazing to watch.

That is so true.  A high speed camera slowing down the action is quite a show.  It is amazing what the wheels undergo during impact.