# GT Karakoram



## tgreathead (Mar 8, 2004)

Just picked up a GT Karakoram frameset at a local swapmeet for super cheap, building it up now but ran into a couple problems. I'm setting it up as a singlespeed for cruising around town, probably won't see much dirt if any. I'm leaning towards a Klunker-ish MTB/BMX hybrid so I can be a little more upright when I ride. Hopefully Someone with more knowledge of the frame can help with a few specifics 

First, the model year. The guy didn't know but from what I've found the black crackle paint only came on the first year, 1988. Sound right? It also has horizontal dropouts, not vertical like I've seen on some other older Karakorams.

Figured out already that I had the wrong seatpost size, am I right that its 26.8? Setback seatpost in the pictures is too small but just in there for reference.
Also seems to be 130mm rear spacing but my 135mm wheel snugged in just fine.
The stem quill size depends on the headset right? I have one stem the same seller sold me that seems to fit, looks like a road stem. I have a BMX stem I'd life to use but is slightly smaller. I'm able to tighten down the BMX stem tight enough that it doesn't seem to move, is this okay or will it come loose when riding?
Also having issues with crankarms hitting the chainstays. I got a set of old Sugino cranks at the swapmeet and the ring actually makes contact. What have others used for cranks? I gathered its a 68mm shell so I might just have to dial out my chainline. Had to substitute with some terribly cheap ones I had laying around.

Alright already, on to the pics


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## cegrover (Oct 17, 2004)

That's a cool frame. I'm not sure on model year, but, if it's 1980s, it's likely a 1" steerer, so you need a 22.2mm stem quill.

On the cranks, I see there was no bottom bracket (BB) with the frame when you got it. Your problem is spindle length, so you can probably solve that with a new BB. You'll need to measure the current one and estimate how much more length you need to clear the frame.

Finally, if you don't already know, note that you'll need a u-brake for the rear, as it won't take a cantilever (or v-brake).


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## yo-Nate-y (Mar 5, 2009)

Looks like it will be an awesome cruiser once you get it sorted!


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## tgreathead (Mar 8, 2004)

cegrover said:


> That's a cool frame. I'm not sure on model year, but, if it's 1980s, it's likely a 1" steerer, so you need a 22.2mm stem quill.
> 
> On the cranks, I see there was no bottom bracket (BB) with the frame when you got it. Your problem is spindle length, so you can probably solve that with a new BB. You'll need to measure the current one and estimate how much more length you need to clear the frame.
> 
> Finally, if you don't already know, note that you'll need a u-brake for the rear, as it won't take a cantilever (or v-brake).


Yup, 1" steerer. I've got a 22.2 stem that I don't really like so I put the BMX (21.1) in there. From what I've read elsewhere it sounds like that's okay as long as the bolt is long enough to tighten it down and get it seated really well.

The crankset you see in the picture fits fine, no clearance issues since the arms have a bend to them, but its a beastly pressfit one I don't want to use. The one I bought has straight arms so I'm guessing that's the problem. I'm pretty sure they're actually road cranks so the straight arms wouldn't interfere with a narrower rear end.

Bummer on not being able to use v-brakes but I guess that's the price I pay for retro 

Thanks for the info!


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## cegrover (Oct 17, 2004)

As some early MTB bars were 21.1, there are shims available to make your BMX stem fit better - not exactly sure where to track them down, but a local shop could have some.


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## tgreathead (Mar 8, 2004)

cegrover said:


> As some early MTB bars were 21.1, there are shims available to make your BMX stem fit better - not exactly sure where to track them down, but a local shop could have some.


Ooh, good to know, thanks


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## muddybuddy (Jan 31, 2007)

cegrover said:


> As some early MTB bars were 21.1, there are shims available to make your BMX stem fit better - not exactly sure where to track them down, but a local shop could have some.


Are you sure those shims are commercially available? I searched pretty extensively a while back and wasn't able to find them.


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## tgreathead (Mar 8, 2004)

muddybuddy said:


> Are you sure those shims are commercially available? I searched pretty extensively a while back and wasn't able to find them.


I've been looking since he posted that, no luck yet. But I may just make it easy on myself and get a 1" to 1 1/8" adapter so my choices will broaden.


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## cegrover (Oct 17, 2004)

muddybuddy said:


> Are you sure those shims are commercially available? I searched pretty extensively a while back and wasn't able to find them.


They were available at one time - I've seen them sell with 21.1 Bullmoose bars before, but they're not necessarily easy to find. A beer can might work?


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## muddybuddy (Jan 31, 2007)

cegrover said:


> A beer can might work?


That's what I ended up doing on mine, but I would rather have a real shim if there's one to be had.


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## tgreathead (Mar 8, 2004)

muddybuddy said:


> That's what I ended up doing on mine, but I would rather have a real shim if there's one to be had.


Does it seem to hold up okay? I don't plan on doing anything with the bike except ride the streets so it doesn't have to be bombproof.


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## muddybuddy (Jan 31, 2007)

tgreathead said:


> Does it seem to hold up okay? I don't plan on doing anything with the bike except ride the streets so it doesn't have to be bombproof.


Seems to be ok, but I haven't done any real trail riding on that bike yet.


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## da'HOOV (Jan 3, 2009)

just don't use material from a "lite" beer can. It won't hold up


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## N10S (Sep 27, 2004)

I purchased one of those new, and I thought it was actually an 87. Too bad it did,'t have the original matching black crackle painted stem.Not a lot of love for old GT's on the vintage forum, but that's a cool old bike and a great riding bike as well. Congrats on finding it and for giving it another chance to be ridden!


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## tgreathead (Mar 8, 2004)

Thanks for all the replies 

I've run into a couple problems again. The seatpost diameter is 26.8, as I've been told, but a 26.8 post I got won't fit in. Looks like the opening of the seattube is slightly ovalized. 

Also picked up a U-brake and got it mostly installed until I realized the internal routing spits the cable out right into the seattube. I realize now I've seen pics of this bike with some sort of adapter that routes the cable around the seattube so it can have a center pull on the u-brake but I don't have it. Might have to improvise.

Good news is I'm taking it to a semi-local shot that specializes in older bikes like this. I'm sure they'll be able to get it up and running no problem. In the future I might look into having them weld on V-brake adapters, saw someone else did that to theirs and it seems like a good idea in the long run.


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## mechagouki (Nov 30, 2007)

tgreathead said:


> Also picked up a U-brake and got it mostly installed until I realized the internal routing spits the cable out right into the seattube. I realize now I've seen pics of this bike with some sort of adapter that routes the cable around the seattube so it can have a center pull on the u-brake but I don't have it. Might have to improvise.


Pretty sure any old cantilever hanger will work for you there, something like this:










set up like this:









(not my images - apologies if they belong to someone here)


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## tgreathead (Mar 8, 2004)

mechagouki said:


> Pretty sure any old cantilever hanger will work for you there, something like this:


HA, I did get one of those with the u-brake but I was setting it up with that piece after the seattube, not before. Yup, the other way makes perfect sense.
I don't have that plastic guide collar but I now see pictures of people without it so I don't think its necessary.
Thanks :thumbsup:


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## da'HOOV (Jan 3, 2009)

I thought it was the plastic collar you were referring to...if you don't have it be sure to run your cables in some sort of cable liner (1/8" vinyl/plastic tubing, like the black stuff in the pic) around the seattube to avoid friction and wear.


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## tgreathead (Mar 8, 2004)

Forgive me if its a stupid question, but does the cable have to cross after the seattube? If I add the adapter you pictured before the tube and the 2 cables ran straight back would that work?


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## da'HOOV (Jan 3, 2009)

there's no such thing as a stupid question...just stupid people who ask them 

Sorry, couldn't resist . The cables need to be crossed to get the proper leverage/pull on the U-Brake.


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## gm1230126 (Nov 4, 2005)

da'HOOV said:


> The cables need to be crossed to get the proper leverage/pull on the U-Brake.


Really?.... U-brake straddle cables aren't crossed on all the other makes of bikes that used u-brakes...does that make them inferior?. What's wrong with the leverage/pull of the U-brake without the cross over cable guide? Is the cable pull really enhanced with the use of the cross over cable guide.

From what I can recall one of the main reasons for the cross over cable guide was cleaner/tighter cable routing and to keep the straddle wire from hitting and rubbing a groove in the seat tube when the brakes were applied. Most other makes that used a u-brakes back in the day did not wrap their straddle cable around the seat tube.

The bike shown at the beginning of the post is in fact a 1988 Model Karakoram and this model year actually preceded the introduction of the GT cross over cable guide. The "Cracked Paint" on this bike was responsible for setting off a wave of interesting paints throughout the industry in following years.


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## da'HOOV (Jan 3, 2009)

well, excuuuse me...It seems to me without the crossover, the distance of the hanger away from the brake would lessen the "angle" of the cable attachment to the brake. Crossing them would put them closer to a 90 degree pull angle. If I'm wrong, I apologize.

I think most other bikes had the hanger behind the seat tube, by using either a cable guide around the seatpost or the hanger was offset, no? Or the brakes were under the chainstays allowing for a straight cable run to the hanger.


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## RickD. (Apr 7, 2004)

da'HOOV said:


> well, excuuuse me...It seems to me without the crossover, the distance of the hanger away from the brake would lessen the "angle" of the cable attachment to the brake. Crossing them would put them closer to a 90 degree pull angle. If I'm wrong, I apologize.
> 
> I think most other bikes had the hanger behind the seat tube, by using either a cable guide around the seatpost or the hanger was offset, no? Or the brakes were under the chainstays allowing for a straight cable run to the hanger.


I always built them with the cables crossed back in the day.


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## cegrover (Oct 17, 2004)

RickD. said:


> I always built them with the cables crossed back in the day.


Crossing cables adds 26.4589783% more braking power.


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## tgreathead (Mar 8, 2004)

cegrover said:


> Crossing cables adds 26.4589783% more braking power.


Then I'll definitely do that then so I can hit some sweet jumps, need to train for Springfield Gorge.


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## Oracle7775 (Oct 31, 2008)

My 91 Karakoram rear brake is set up like the picture above, with the cable crossed over.

Good luck with the bike. I turned my cheapo Karakoram into a single speed, and it rides really nice.


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## tgreathead (Mar 8, 2004)

Got the bike finished today and took it for a spin tonight, came out great! The brakes are still an issue, they kinda suck. I tired both ways, crossed and straight. Crossed seems to be a *slight* bit better. Also picked up a coaster brake wheel for cheap, might go that route...

I'll take pictures tomorrow. Went on a big group ride tonight, got tons of oohs and ahhs and LOTS of people wanted to know "what IS that, its awesome!!"


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## Oracle7775 (Oct 31, 2008)

tgreathead said:


> Got the bike finished today and took it for a spin tonight, came out great! The brakes are still an issue, they kinda suck


Yeah, I forgot to mention that the rear brake, even when it is set up correctly, kind of sucks. Maybe some nice brake pads would help, instead of the cheap-o's I have on mine. That's the main reason I put a decent set of V brakes on the front wheel, to make sure I have good stopping power on at least one of the wheels.

Look forward to seeing the end results!


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## mrjustin007 (Jul 22, 2008)

I have a Karakoram,and a Richter 8.0 both with a u-brakes. When set up properly they are just as good as v-brake -(IMHO). There are a few u-brake set up threads, I read and followed the advise and played with them till they worked. You can also find the plastic cable guide at most shops, alot of BMX bikes still use them.


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