According to 2 of my service manuals the torque is 30-45 ft-lbs, and 75% of yeild for 3/8-16 fasteners is 37 ft-lbs for zinc plated fasteners. There is no mention of prohibition on re-use of the bolts in my 02 softail book, but is addressed (no reuse) in my '10 FLHTCU manual, with the same torque spec.

 

I dont know why they say to replace them, but on my Fatboy back in 05 the Dealer used the same ones to install the Chrome Pulley when I bought the bike (assume this because I was not charged for new ones) and 7,500 miles later the pulley came loose after 3 came loose and the bots were broken, heads off them.

The original dealer that installed the chrome parts warranted it and the service manager explained to me that it should hve had new bolt kit used.

 

Yep, the rear rotor bolts are 3/8 and the fronts are 5/16

3. If removed, install five T45 TORX screws (and locknuts on laced wheels) to fasten brake disc to hub. Always install brake disc in its original position. Use

 

+1, it's stated in my 01 EGC manual.

 

Here's my thinking for the reason HD recommends replacing the rotor bolts (in addition to the liability factor)... This is only a thought and I'm not saying this is the reason, but it makes sense to me.

The highest stresses the rotor bolts will ever see is not from torquing them, and not from any forces during operation, but from removing them. New bolts have a high strength loctite on them and if you've ever removed a brake rotor you know how much torque it takes to break them loose. That rotational force applied to the bolt head when removing them is the highest stress they will ever see and probably comes closer to actually yielding the bolt than any other forces. If the bolt does yield, the location of the yield will be near the bolt head to shank, and it will permanantly weaken the bolt.

If it wasn't for the high strength loctite on the factory bolts there would probably be no reason to ever replace them.

 

I think you got it spot on, it takes more force to break loose that locktite, and since they are torqued to limit to start with, there is a good chance they will yield when loosening. Front and rear being different sizes, and both have locktite, why are the rears good for three use cycles and the fronts good for one use? There is no call for use of locktite in the manual so do these bolts come new with a threadlocker patch?

 

Well, i guess if my rear rotor falls off, I was warned.

 

I agree. The manual does not refer to locktite. Should I use blue or red with new chrome bolts?

Thanks,

Scott

 

blue, go in a star pattern, go 50% of torque value on first pass, then full tq value 2nd time around.

~Joe

 

They come with lock patch on them. When re-using old bolts... I would use a thread restorer and go with blue.

I always bought new bolts for crap that needs it.