Front Axle Nut Torque

For as long as I've had my bike, I've always torqued the front axle nut. I haven't given it the full 78 ft/lb, but more like 50 ft/lb. A coupla days ago, I replaced front brake pads and reinstalled the wheel. This time I spun the wheel as I tightened it. As I tightened, resistance against the wheel spin increased dramatically. I went to about 50 ft/lb and backed it off, spun and retightened. I wound up with about 5-7 ft/lb for minimal spin resistance and found it to be more than enough to have a solid (no wiggle) hold on the axle. I put a new cotter pin in, then went for a ride, filled the tank---refilled after 110 miles with just 2 gallons. Yep, 55 mpg from mixed riding. Since I recently had to go back to my mac 4 into 1, I had been getting 46-48 mpg. I've done an ultrasonic test on the bearings and they're great. (I used to own a bearing analysis service). I'll do another in a coupla days. Can anyone point out a safety issue or impending calamity? I'm wondering if we can beat the oil cartels by letting our front wheels spin a little easier.

 

It shouldn't do that if you leave the pinch bolts loose, and bounce the front end a couple of times after tightening the axle but before torquing the pinch bolts. The whole thing is designed so the axle tightens against the RH fork; the LH fork needs to be able to "travel" a bit on the axle to find its happy spot. After the axle nut is tight.

I WOULD NOT ride around with an axle nut that's supposed to be at 76 ft/lb tightened to 5~7 ft/lb. Something ain't right or you "stacked" the parts incorrectly. My front axle nuts are all torqued to spec, and all of my front wheels spin freely (multiple XJs.)

Danger, Will Robinson! Re-investigate.

 

Pinch bolt is always last, after working the forks. I just ran over 200 mi yesterday and all is well. I will disassemble tomorrow and look for any issues.

 

Use the Holes drilled through the end of the Axle to help get the torque right without turning the Axle.

A Screwdriver or a Line-up Tool passed-through the Axle will help you get Torqued or hold the Axle so you can get the Castle Nut moved a bit to allow the Cotter Pin to fit.

 

You may have been "mashing" the ears on the speedo drive ring flat as you tightened...

 

Ricko: That's the way I've always done it.
bigfitz52: No mashing, all parts in good condition. I've got it apart at home. I'll do more inspection this evening.

 

It's also possible that your RH caliper isn't "floating" properly, causing the brake to bind up wheel rotation.

 

After close examination, it seems there was a small amount of mud, shmagma or other debris in the axle hole of the right fork (pinch bolt side). The debris must have restricted horizontal travel of the axle while tightening, with the pinch bolt loose, enough to cause a slight pinch of the forks on the bearings. After a thorough cleaning, all is well and the axle nut is now torqued to the recommended 78 ft/lb. without any added friction to the bearings. Wheel spins freely. Thanks all for helping me get this sorted out.