discovered that one of the bolts that goes in on the right side of my 99 fatboy seat was cross threaded an wanted to know if anyone knew what size tap it would take to straighten it out. ive looked at the bolt an I think its ok

 

Why not just pick a new one up at Harley and replace it. It's a little hard to get up under the fender, but it can be done..

 

its not that one, its the one on the side of the drivers seat, there is one on left and right side. its a 99 softail fatboy

 

going by memory here sp not 100% positive but i think they're 5/8"-11

if you have a caliper or a micrometer, measure the o.d. over the threads,

if it's right around .625" it's 5/8"-11
if it's right around .500" it's 1/2"-13

 

The "no guess method" involves a bolt sizer/thread pitch gauge.

 

I just put new bolts on my 97 Springer solo seat. It's a 1/2"-13 bolt

 

FWIW, if the threads are goobered up, a tap is not your best choice. A tap will cut new threads, and remove material in the process, leading to a weak/loose fit. A thread chaser will restore the threads without removing material.

 

thanks folks, ill try to chase the threads first and try it. if that don't work ill use the tap. shouldn't be to hard to fix I just didn't know what size tap or thread chaser to use. thanks a bunch.