Hi everyone.

I just wondered what your opinion is on brake mounting standards.
Which front fork brake mount is better – Post or IS?

My reason for asking is that I may buy a 2008 Fox Talas front fork with IS mounts.
My brakes will fit with the correct IS or post adaptors, but it seems that all the new forks are post mount.

What are your experiences with the different mounts, any pros / cons…?

Thanks for your advice.

tBike

Post mount is easier to adjust side to side for getting the calliper centred over the rotor.

Neither is that much better than the other that it should influence fork choice provided they fit your brakes.

not much in it imho

I think that some calipers bolt straight on to a PM fork so they can be used with a 160 rotor without an adaptor but I’m not sure 😕

Given the choice I would go for IS as you can always get adaptors to fit Post mounts.

There’s only one way to find out…

Thanks for the advice, much appreciated.
I did wonder if post was more stable and robust due to the torque stresses from braking.

Clearly busting the threads on a post mount is not good.
Thank goodness for adaptors!

– can’t strip a thread on an IS mount…
– post mount easier to adjust though

adpators are available to fit pretty much any calliper to any fork so not much in it compatibility wise.

Post mount (with post mount caliper) will be lighter in 160 with no adapter or upto ~185mm with longer bolts+staight through adapter (203mm pm-pm ime require more bolts)

I prefer IS fork with a pm caliper for lack of thread stripping woes and for fork lowers servicing you can leave the caliper adjustment of the pm caliper on the adapter and just remove/refit on the is fork-adapter

IS caliperscan be a pita to setup trying to get the right combo of washers, or worse if your choice of hub/caliper/fork means it will rub but spacers would make it worse ..

is mount talas from 2008?
im most likely wrong, but i (in the back of my head) thought 2008 fox were post mount? not sure why
I know 2008 F120’s are post mount? though obviously they’re not talas 32/36

IS mount wouldn’t bother me, if its a 36 and its got bolts to clamp of the axle instead of QR levers then I’d more concerned (pita, risk of rounding/stripping bolts etc .. )

IS forks are ideal to my mind fit any PM caliper with an adapter and no risk of stripping the threads in your posh pricey forks… feels like another little effort at building in obcelesence to me…

IS mount is much better.

a moment of ham-fisted madness can only knacker a £6 adapter, not a £200 fork-leg-casting…

a moment of ham-fisted madness can only knacker a £6 adapter, not a £200 fork-leg-casting…

A Helicoil fix kit is only £15 (I know, I stripped a thread on my Talas forks).

I rather like that you can unbolt an IS mount from a fork and then reattach it without having to adjust anything. Whereas with PM, you can’t remove it without readjusting.