confusion on Steering Stem Lower Ring Nut Torque setting

[Rdecae81]

I am doing a reset of the Steering stem Lower Ring nut

Page 3-20 of the Yamaha service manual
Lower Ring Nut initial torque = 52nm

Lower Ring Nut Final Torque = 18nm

One what am I missing

Two anyone know the correct Torque for the lower ring nut?

 

[betoney]

8 minutes ago, Rdecae81 said:

I am doing a reset of the Steering stem Lower Ring nut

Page 3-20 of the Yamaha service manual
Lower Ring Nut initial torque = 52nm

Lower Ring Nut Final Torque = 18nm

One what am I missing

Two anyone know the correct Torque for the lower ring nut?

 

I just looked at the service manual on my older 2015 model and it says the same thing, very confusing.  Yamaha manuals and specifically some torque figures are known to be questionable.

@skipperT - do you have any insight on this?

[2and3cylinders]

If I'm not mistaken, and I certainly could be, the initial setting is used after replacement of new bearings, cages and races to "bed" them to each other.  Then after this first tensioning you're then to back-off the preload and retension using the second lower setting.

I usually pretension based on feel because it is often difficult to use a torque wrench for this procedure.

The goal is to have them bedded snugly but not overtightened so that the cages are crushed and races dinged.

Honda, for example, specify how to check the force needed to turn the forks using a tension scale like a fish weight scale (I have a digital scale that is metric & inch that goes up to 85#s).

[skipperT]

4 hours ago, betoney said:

I just looked at the service manual on my older 2015 model and it says the same thing, very confusing.  Yamaha manuals and specifically some torque figures are known to be questionable.

@skipperT - do you have any insight on this?

Sure, follow the book. 🤣

I’ve used those figure many times over the years. @2and3cylinders pretty much covered it above, but what the Factory means is to initially torque it to 52 Nm, loosen the nut, and re-torque to 18Nm. I would add that I typically rotate the lower triple tree back and forth several times to help seat everything and give an accurate torque figure. I then torque the nut again, wiggle the stem, and tighten it a third time. Install the rubber washer, install the upper nut BY hand, line up the notches and insert the locking plate (if any). 
 

I also like a higher torque figure (probably around 22-25 Nm as a final torque if using stock bearings as long as they don’t bind. Helps with the steering head shake of these and the MT09 models. 
 

if using tapered bearings (Allballs, etc) the factory specs should be used as a guideline only, usually those require a higher torque figure to keep them rotating, not binding, and not clunking. It’s really a “by feel” method more then anything if using aftermarket bearings (which are WAY better than stock!)

If you look up how to set Fall-away on Harley Davidson soft tails, sportys, or Dyna models you can use a similar process after you’re done to see if it’s in the ballpark of good tightness without having to test ride and re-adjust.

I don’t have time, but I’m sure there’s YouTube vids out there…

-Skip

 

[piotrek]

1 hour ago, skipperT said:

Factory means is to initially torque it to 52 Nm, loosen the nut, and re-torque to 18Nm.

I will just add... loosen, but not enough for the bearing/races to separate.

[Rdecae81]

yes watched a video and you are correct, I understand now.  thanks.