GT STS Formula Disc Brake Swap?

[DesertRyder]

What are my options for different disc brakes on a GT STS DH?

What would I be looking for? I can't seem to get any brake pressure in the factory Formula brakes.
No major downhill riding. I see a few sets on ebay by Zoom? I believe they would suffice for my type of riding?

I've bled and 99% sure there is no air in the line. No pressure in front brakes=No brakes.

I haven't progressed to the rears yet.

Shop quotes me $40 USD for each brake bleed with no guarantee they will work. They say because of age they can not guarantee.

FRONT


REAR

 

[B3]

Check the mounting dimensions, http://www.peterverdone.com/wiki/index.php?title=Shimano_Framebuilder_Info they look like IS to me. If they are, then any modern brake will fit.

 

[DesertRyder]

What I found last night.

Front with adapter already on bike: 51mm international standard
Rear mount: FS 48mm mount.
rotors measure 165 mm

I think this bracket would work on the rear

 

[clubby]

Could be way wrong but is there anyway of using the front mount adapter on the rear? Lateral spacing may be out but can always use longer bolts and some washers to get spacing right. At least the mounting holes would be in the correct vertical position.

You won’t need an adapter on the front anyway if moving to IS brakes.

 

[ishaw]

I don't think you need an adapter, the one you have pictured is I believe for the sts/lts rear ends that didn't have a disc mount on the rear arm, but had bolt holes to fit the one in your pic. I'm no guru, but have had a few sts builds and a few lts.

The brakes you have, and the mounts do look like the common IS spacing, so and brake should fit with the same standard.

I don't know about the cheaper disc brakes, but I woul personally go with something better as the frame deserves it, and you want to be able to stop reliably when you need to