Desert Ryder

Are there any other GT owners with the thermoplastic carbon frame?
Does anyone have parts sitting around?
Curious to see what's out there.

My STS DH that is sidelined due to hydraulic brake issues. I'm possibly hunting for something to update the brakes. Preferably cable operated for ease of maintenance.

veganbikes

That is a blast from the past. If they are using standard ISO or Post mounts you could easily get a different brake on it. I would just put on some Shimano hydraulics and be done with it, they are good and reliable and easy to source and use mineral oil. If you are desperate for cable brakes TRP Spykes with Jagwire Elite Link kit for cables and housing in red of course and Paul Levers or if looking to be a little less costly Avid Speed Dial 7s but I honestly wouldn't want to not have hydro brakes. I just might not want those particular brakes.

I would also go for Magura brakes but it is a difference in feel, I like both but have certainly now probably put more time on Magura but have ridden a lot of different bikes with Shimano over the years.

Desert Ryder

I found out the caliper mounting is a non standard 48mm. A few mm smaller than IS 51mm mounts.

Supposedly, a Hope C2 Number 4 caliper is a replacement but that may just as hard to find as original Formula parts.
I would prefer to keep the bike as original as possible though. A rare bike brings all its own problems.

Let's see some more thermoplastic carbon rides.....

Due to the bike's age, and my age, hardcore downhill bombing is off the menu.
Regulated to mild downhills and country trails...

Kapusta

Assuming the frame and fork are either standard post mount or IS tabs, there are countless options.

Since this is a pretty old bike (90s, correct?) if you have post mount I would measure the center to center distance to be sure they are the same as the current standard. I forget what the measurement should be.

If you want to go mechanical, I’ve used Avid BB7s for years and many and for me rhe MTB versions have worked really well and are affordable, especially if you already have some v-brake levers sitting around. But they are tricky to get set up just right, and you do need to twiddle a couple adjuster knobs every so often to keep them really well. If you run them for long not properly adjusted, the pads wear unevenly and it becomes really hard to get them running well again. Most people don’t do these things, thus they get a reputation for sucking..

For a bit more money you can get TRP Spykes, which are much easier to set up and maintain and by all accounts work very well, though I read a lot of reports that the pad adjusters can move on their own.

For really big bucks you can get Paul Klampers. I’ve read nothing bit praise for those, but they are very expensive.

Edit: just realized you already measured the post mount and it is an old standard….

rosefarts

About 10 years ago I saw a Thermoplastic LTS in a pawn shop in Denver.

I was between jobs and just about to go back to school, no extra money but damn, I was tempted. I still occasionally regret letting it go (it was cheap and in rough shape, likely a wall hanger).

veganbikes

Oh shoot, then you are in some trouble unless someone makes an adaptor which someone probably did at one point. Nevermind here we go: https://www.sellutionmtb.com/Product...Code=BA%2DGT02
https://www.sellutionmtb.com/Product...Code=BA%2DGT01

I wouldn't ride that thing downhill, so many excellent DH bikes these days and plenty of Enduro and other stuff which would be better suited. Vintage bikes for DH just seems sketchy to me but I am a crappy MTB rider so it could just be me being rather nervous and lacking skills.

Darth Lefty 

That thing is wild. From the era where people had figured out how to make suspension do what they wanted but they still hadn't figured out if what they wanted was actually good! And they were all fighting it out over patents

nomadmax 

What's the red thing on the lower chain run behind the crank?

Desert Ryder

It's a original AC (Adventure Components) chain guide/tensioner for downhill

Desert Ryder

Apparently, I am a lone ranger with this type of bike?

Are they really that rare?

Kapusta

At this point GT STS bikes are pretty rare.

That is about 25 years old , and the design was retired by ~2000.

For starters, DH oriented frames tend to be ridden pretty hard and don’t have long lives when used as intended.

At this point most still around are either in the back of someone’s garage that has not been riding much for the past two decades (and would likely not be on a MTB forum), or are vintage collectable interest bikes. You might try the Vintage/Retro board on MTBR.com.

But your specific question here has little to do with the bike itself. It’s about the brakes, which are not unique to that bike.