bolt sizing

[development_cycle]

want to replace the bolts on my Avid Tri align brakes as most of them are looking rough. How do I work out the whole M5/M6 business?

Anything else I need to know?

 

[JeRkY]

get a pair of verniers and stick them accross the diameter of the existing bolt.

 

[development_cycle]

In between the threads or on top of the threads?

What do I then do with that measurement?

 

[andy.l]

top of the threads,most canti pivot bolts will be M6's but some American stuff can be different

for english stuff,if you can fit an 4mm allen key in the head its an M5,and if you can fit an 5mm allen key in the head its an M6 thread

 

[development_cycle]

cheers guys if only I had known it was that easy!

 

[SLIM]

found this quite usefull .............

 

[cherrybomb]

Remembering that the '6' in M6 in a nominal diameter. If you measure the diameter with calipers it will be less than 6mm, more like 5.8mm.

 

[B3]

Remembering that the '6' in M6 in a nominal diameter. If you measure the diameter with calipers it will be less than 6mm, more like 5.8mm.

Good point well made.