Old school carbon GT

[floody]

Cool!
I'd like to do the same with an LTS-DH or LTS-xxxxDS, as I'm sure the frame design would make for a good pedalling, reasonably light All mountain rig with reasonable geometry. In the end its an FSR bike with pretty typical 90's XC geometry, so it should work.

As the other poster said, yours must either be post warranty or one of the last imports of the STS's, which is lucky for you as they're quite a bit stronger than the visibly lugged headtube version.

 

[ohalrighthen]

Hey, thanks for comments!

I had a decent off not long after building it up so have only ridden about 3 times on it but the Coupe Deluxe seems fine. I bought it with a blown Fox Vanilla Air and have a Fox Float RL from a Jekyl that I may put on it, but will need to get the trunnion mount bored out slightly to fit.

I don't mind the Recon. Doing the old carpark bouncing test I thought it had too much compression damping (not externally adjustable...) but it has been great off road. It's set at 100mm at the moment, which is the same travel the DS's came with originally (dual crown Rock Shox XL's) so doesn't affect the geometry at all. To be honest, I've probably had the back end set a bit too high if anything so the 130mm setting will probably make for a better balance. Will keep you posted as I experiment!

Does your LTS-1 have the originally titanium linkage or the later aluminium trunnion mount version like mine?

No worries, good to see someone who actually cares about their classic, building it up with thoughts and care, unlike the previous owner who I brough my Xizang from, a total neglect.

Mine LTS came with the trunnion mount, which I believe is identical to yours. It also came with 2 shocks, one Fox Vanilla Air and the Exxon Valedez version of the Super Deluxe. I found the Fox Vanilla Air way too progressive for my liking so I'm going to perserver with the Super Deluxe. I just took delivery of a brand new Super Deluxe from my US contacts last month, no leaks but it has really weird compression and rebound circuit. I guess I'm spoilt on the Fox dampers so I might be expecting too much from 10 year old technology.

I've thought about getting an Fox RL for Cannondale Jerkyll as well to see if it fits, and I'm glad you've already had the experience & it will be interesting to see how you go wedging that into your LTS.

Does your rear end come with factory disc brake mounting tabs? Mine is runnning BEDT LTS adaptor which looks chunky and ugly, but at least running disc brakes elminate the famous "stink bug" effect LTS is known for under hard braking when running V-brakes.

I had an 96 LTS-3 with titanium linkage, which is currently sitting at my friends house collecting dust. I might buy that bike back from him someday.

 

[ashes_mtb]

No worries, good to see someone who actually cares about their classic, building it up with thoughts and care, unlike the previous owner who I brough my Xizang from, a total neglect.

Mine LTS came with the trunnion mount, which I believe is identical to yours. It also came with 2 shocks, one Fox Vanilla Air and the Exxon Valedez version of the Super Deluxe. I found the Fox Vanilla Air way too progressive for my liking so I'm going to perserver with the Super Deluxe. I just took delivery of a brand new Super Deluxe from my US contacts last month, no leaks but it has really weird compression and rebound circuit. I guess I'm spoilt on the Fox dampers so I might be expecting too much from 10 year old technology.

I've thought about getting an Fox RL for Cannondale Jerkyll as well to see if it fits, and I'm glad you've already had the experience & it will be interesting to see how you go wedging that into your LTS.

Does your rear end come with factory disc brake mounting tabs? Mine is runnning BEDT LTS adaptor which looks chunky and ugly, but at least running disc brakes elminate the famous "stink bug" effect LTS is known for under hard braking when running V-brakes.

I had an 96 LTS-3 with titanium linkage, which is currently sitting at my friends house collecting dust. I might buy that bike back from him someday.

I'm using an A2Z disc brake adapter at the moment. It works fine but makes it difficult to remove the rear wheel. There is a small crack in the seatstay which I'm sending to Gripsport to be fixed up properly and will get them to chuck on a permanent disc tab then.

The trunnion mount is a great idea, I really like to play with the bikes geometry and set it up to my preferences, but its a pain changing the travel chip and its a shame you can't upgrade to modern shocks like you can with more conventional designs. At some stage in the future if I blow the shocks out i may get a conventional upper shock mount added to the top of the upper link. May look ugly but could be the only option in the future.

 

[ashes_mtb]

I've got me a 97 STS frame hanging in the shed. Bought it from NZ for a build up project with the intention of sourcing all old skool parts and building it up as it would have been, back in the day.

It'll be a slow and pricey process but I'll get there...cant wait to finish it and post some pictures

Sweet. The 97 STS is really the classic one, with the alloy lugs front and rear, its a 'prettier' looking bike than the DS.

I contemplated an original build but its my regular ride so wanted something reliable, plus the older gear is getting pricey and hard to come by so its cheaper and easier to go down the modern route.

If you haven't seen it already, check out www.retrobike.co.uk Its a great resource for those into older mtb's. People on there are very friendly and supportive and are great help if you're after a hard to get part or need advice.

 

[ohalrighthen]

I'm using an A2Z disc brake adapter at the moment. It works fine but makes it difficult to remove the rear wheel. There is a small crack in the seatstay which I'm sending to Gripsport to be fixed up properly and will get them to chuck on a permanent disc tab then.

The trunnion mount is a great idea, I really like to play with the bikes geometry and set it up to my preferences, but its a pain changing the travel chip and its a shame you can't upgrade to modern shocks like you can with more conventional designs. At some stage in the future if I blow the shocks out i may get a conventional upper shock mount added to the top of the upper link. May look ugly but could be the only option in the future.

I didn't know A2Z made a disc brake adapter for LTS. Does your LTS dropout have 2 holes in it? The trunnion mount had me puzzled for awhile, as I couldn't work out how to get the shock out of the rocker cradle. I think Cane Creek makes Cloud 9 shock for LTS - I can't find any information on their website but I do recall seeing a picture of an STS with same rear stay like yours, with a Cloud 9 air damper inside.

I didn't know that LTS has 125mm of travel. That's more than my 04 I-Drive 1.0 My last LTS had 90mm travel - I guess GT had to redesign the rear rocker to include the trunnion mount to accomodate for longer shocks as the original LTS had too high a shock ratio to make it work properly.

 

[ashes_mtb]

I didn't know A2Z made a disc brake adapter for LTS. Does your LTS dropout have 2 holes in it? The trunnion mount had me puzzled for awhile, as I couldn't work out how to get the shock out of the rocker cradle. I think Cane Creek makes Cloud 9 shock for LTS - I can't find any information on their website but I do recall seeing a picture of an STS with same rear stay like yours, with a Cloud 9 air damper inside.

I didn't know that LTS has 125mm of travel. That's more than my 04 I-Drive 1.0 My last LTS had 90mm travel - I guess GT had to redesign the rear rocker to include the trunnion mount to accomodate for longer shocks as the original LTS had too high a shock ratio to make it work properly.

Yeah, my drop outs have the two holes. Have seen a 99 version on the net that came with disc brake tabs standard.

The A2Z adaptor is just a generic one, works on most bikes with flat drop outs. Your BETD would no doubt be a better fit than the A2Z.

The DS LTS/STS versions like mine were adjustable from 4" to 5" and had a more relaxed head angle. Catalog said around 69 degrees but obviously that can be adjusted a fair bit with the trunnion mount.

I'm surprised the shock ratio was too high on the originals. Both the standard trunnion and DS trunnion versions used the same shocks (which i think are 1.5" stroke) so they were around 3:1 at the higher travel setting.

 

[ohalrighthen]

Hmm you might be right. I think your knowledge of LTS is better than mine.

All I can remember was that my original self-exploding Super Deluxe unit on my 96 LTS had a 1" stroke to get 3.5 inches. I might be wrong though it might have been 1.25", but it was definately less than 1.5" stroke.

Which makes me wonder - my new Super Deluxe has aroudn 1.5" of stroke so at 100mm travel setting, I'm getting leverage ration of 1:2.67, and at 125mm setting it will be at a ration of 1: 3.27 - this could be the reason that shock have weird compression and rebound damping characteristics. Do you know if inverting the plastic chips in the trunnion mount make any difference?

I was a bit surprised to see my LTS having identical head angle to my I-drive 1.0 with TALAS set at 130mm, when the Float on the LTS is set at 100mm, so if I had LTS at 5" to match the rear end, I'll be steering a bus in the single track running 68 degree head angle. I thought the LTS were built to 71 degree and I buggered it up by sticking a modern day Float on it. I feel better now - thanks for that piece of info!

 

[ashes_mtb]

I'm not certain about the stroke lengths so I could be wrong... The one I bought is 1.5" so just assumed it was the same for all the trunnion versions.

Your LTS was built for a 3" 80mm fork, and set for a head angle of 70.5 which was the GT standard back then. So yeah, a 100mm fork, not to mention 130mm, would throw it out a bit. You might be able to jack the back end up a little by screwing down the trunnion mount to balance? The plastic chips are designed to alter the travel. On yours, the front setting (closest to the seat tube) will give you 3.5" (~90mm) and the rear setting will give you 4.5" (~115mm). I don't think the plastic chip affects the angles though, that is done by winding the shock up and down in the trunnion.

The DS was designed around a 100mm fork but had a slacker head angle to better suit its intended purpose. Doesn't bother me too much as I ride for the downhills, as long as it gets to the top eventually I'm happy. If you want it for more traditional xc purposes though it could be too slack.

 

[ohalrighthen]

Wow, thanks that's a lot of useful information, I'll have a play with the bike to see if I can balance out the front & rear by resetting the Float fork down to 80mm.

I'll be happy if I can reach a head angle of 69.5 degrees, I guess I might end up with 80mm / 125mm setting in the end but at least it will steer better between the trees.

 

[KA0S]

For out, you wouldn't think it was the old, nice find

 

[Misplaced]

Sweet. The 97 STS is really the classic one, with the alloy lugs front and rear, its a 'prettier' looking bike than the DS.

I contemplated an original build but its my regular ride so wanted something reliable, plus the older gear is getting pricey and hard to come by so its cheaper and easier to go down the modern route.

If you haven't seen it already, check out www.retrobike.co.uk Its a great resource for those into older mtb's. People on there are very friendly and supportive and are great help if you're after a hard to get part or need advice.

Great link, thanks mate.

She is a good looking bike alright and it will be restored to former glory. I am lucky to have a few other bikes as my normal rides so this build is all about museum quality. Some of the parts I put on will be more of a nod to the era than to actual function, stay tuned...

 

[cj_biker]

cool shaped frame

 

[ashes_mtb]

Wow, thanks that's a lot of useful information, I'll have a play with the bike to see if I can balance out the front & rear by resetting the Float fork down to 80mm.

I'll be happy if I can reach a head angle of 69.5 degrees, I guess I might end up with 80mm / 125mm setting in the end but at least it will steer better between the trees.

If you can live with short travel on the front, the old GT's with the 70.5 HA were great handlers. Well worth playing around with all the different settings though.

You should post some pics too, you don't see too many of the old GT's around anymore.

 

[ohalrighthen]

Well, here's some images of my LTS-1, bought from eBay in USA, restored with whatever I have kicking around at the moment... The bike frame arrived with non-original decals, but a can of alloy polish later with some factory original decals from Santa Ana fixed it up nicely.

Still need to go around an play with the geometry / ride height so the bike can corner like a GT should.

The Bedt disc brake mount looks a bit cobby, but does the job.

New Rock Shox Super Deluxe damper at the rear to replace the original Fox Vanilla Air and leaking Super Deluxe unit. The unit in the bike at the moment is nearly 1" longer than the original! Maybe I have a damper for the later model DS version...

 

[ohalrighthen]

Well, took the old girl for a spin this morning and much to my surprise, it actually rode very, very well! Just about as good as my GT I-Drive 1.0 and in some parts, better than the I-Drive. The only downside I've experienced in this morning's ride is that a couple of the linkage bolts working loose & took a bit of faff to dial in the slightly eccentric Super Deluxe rear damper. Also, I'll probably in the future replace the Float fork with a Vanilla, to balance feel between both the front and rear end. At the moment the front is feeling overly progressive compared to the linear coil rear end.

I've forgotten how well the true Horst link 4 bar linkage design works. You can really feel the rear end staying fully active under braking over the bumps into corners, and square hits are not as harsh feeling as the I-Drive. My worries about the steering being thrown out with the longer Float fork turned out to be a non-issue in the end. Cornering was accurate and got that good old GT feeling back when jamming into turns, with the rear drifting away first while the front end staying put. Awesome.

I didn't think a 10+ year old rig can ride so well - definately put some other current generation bikes into shame.

 

[ashes_mtb]

Mate, that LTS is really nice!!! I agree that they ride as good as the newer designs. I've never really thought all the pedalling platforms were necessary (at least for general trail riding anyway), and they seem to hamper the suspension action a bit when you need it.

The new shock might have been for an LTS DH, which came with a longer shock. Where did you get it from?

 

[ohalrighthen]

Thanks Ashes, I agree some bikes needs platform damping shocks to make it more "rideable" but I guess the GT dual suspensions were designed before platform damping were in vogue, so it has been designed to cope with pretty basic dampes.

Hmm I think you might be right - that Super Deluxe is pretty long, so might be made for a longer travel LTS design. I got my shock from a contact I have in US - I see him on eBay once awhile selling off some really old stuff so if you're looking for one, I can send you his contact details.