Double Seat Clamp question, read in!


About to go to bed, but I’d like to ask this first!
Assuming I do end up building up my ‘The Ti’ frame , I’ll need a seatclamp for it for starters, but I’d like to get a double clamp one just to be assured of the extra clamping force and also I tend to find that single clamps, almost no matter what, seem to ‘squash into themselves’: in the sense that the bolting force flexes it so far to the point the two ends touch eachother= loss of clamping power.

I could get a Koxx/KH clamp, but here’s the tricky part: My frame’s neck has a short slit at the top so it’s best suited for lower profile double seatclamps. The KH and Koxx ones are a little too tall, and I can’t be bothered to file/grind them shorter.

I stupidly threw away the original double clamp Zack and Dan were using on this frame because I stripped a thread from overtightening, and only afterwards realised I could’ve easily helicoiled… doh! :o

So… to the point:

Do you know where I can get a 31.8mm double clamp (i.e. same inner diameter as KH/Koxx) that has a short height? I’ve been hunting around and this is the only one I can find so far:

If you’ve seen any around on the internet or at your local store, give me a shout!



Dinnnggg! Anyone know?

Option 1 would be to cut the slit a bit deeper. I know you’ll probably get through a few hacksaw blades (or grinder discs), but that seems like the sensible option.

Alternatively, even though a double seat clamp might well be deeper than the slit, you don’t have to seat it all the way down on the frame. As long as the bottom bolt is not lined up with the solid part of the frame then you’ll still get the maximum effect from the clamp.

One of the Uni magazines featured a group test on seat clamps a few months ago. I can’t lay my hands on it at the moment, but if you can get hold of a copy it might give you some good suggestions.


Ah, which issue was that one,? Can anyone offer me the names of the double clamps in that review section please?


By a process of deduction, it must be issue 5. That’s the only one I can’t lay my hands on at the moment. I’m sure someone has a copy though…


I reommend the hope single bolt. I use it and its just as tight as a double bolt. The review even noted that while it was expensive it was by far the best single bolt clamp and rivaled many of the double one at 66nm. The salsa flip lock got 72nm. Hope flip lck got 68nm.

Double bolt ones in the issue are :

k1 24 - 63nm
kh - 50nm
k1 2 bolts - 68nm
onza - 47nm
nimbus (25.4,22) - 77nm

what those numbers means? on mine it’s written 6nm and the one that Sponge posted it’s written 5nm on it.


the force what is the maxium that you can put on the clamp
or google newtonmeter i cant explain it bether in englich

I had the Hope single bolt clamp but didnt like it at all. It uses quite a small sized allen key and I couldn’t get it tight enough with my standard sized key. Then I rounded the head of the bolt but was probably my fault for using someones cheapy multitool. Switched to standard KH double bolt and thinks its great, maybe doesnt answer your question though.

Get a good single bolt clamp, the best one is Salsa ($20). I’d avoid the Salsa fliplock, it works, but getting it tight enough is hard and the lever could snag your leg.

The 5NM refers to how tight you can crank down the clamp bolt. 5NM is nopt much, 10NM is max for an Animal single bolt. You could also hacksaw a double clamp to fit.

If you really want a solid single bolt clamp, you need to find one that uses a bolt and nut, the aluminum thread single bolt clamps will always strip in time. Use grease and a torque wrench.

I have a Salsa fliplock on two unis, and have had no problems at all. It holds like anything, and the lever actually curves around the base, so lays flat and is very unobtrusive when closed. I highly recommend it, especially if you’re using dual-hole cranks and need to adjust your seat height regularly.

i think you should make some custom Ti ones. That would be awesome. I know we are making some billet alu ones for our carbon frames that will be double bolt. i want to try and make a double bolt that is as strong and light as a single bolt, so they should be pretty cool when they are done. Im not sure if they will be the right size though becouse we might make the neck carbon larger if we decide it needs it. i will let you know when they are done though.