Surly seatpost clamp sucks -- Salsa lip-lock cured it.
 

Hey, I love my LHT but have had the issue of having to really torque the "Surly constrictor" collar that came stock to keep the seat post from moving around. I finally torqued it down too tightly when adjusting the saddle position and it snapped.....

I bought a salsa lip-lock and noticed an immediate improvement in holding power when I installed it (i.e. it took probably less than 1/2 the force to tighten it up than the surly).

Just wanted to plug for this collar -- it's great:thumb: I thought I had issues with frame construction, but I think my problem was with the stock collar alone.

Are you sure your seatpost is the right diameter? Is the seatpost carbon? I have a Surly Cross Check and am using the Surly supplied seatpost collar and an Easton aluminum seatpost. Tightening the collar bolt modestly has kept the seatpost firmly in position and nothing has ever moved. .

We sell a lot of Surly's in our shop, the LHT's do require more torque than average to keep the post from slipping. I've even broken a bolt before in trying to keep the post secure. It's doable, but I can see where a Salsa clamp would be helpful, their design does produce more holding power with less stress on the bolt.

I wonder why the LHT's require so much effort to make their seatpost clamp work when my Cross Check needs nothing out of the ordinary to keep the seatpost in place..

I don't know, and we've sold a lot more LHT's than Cross Checks, so I'm more familiar with the issue in regard to the LHT's, never noticed it on Cross Checks as far as I can remember. I have an LHT myself that I built up from a frame, and I used a Nitto 27.2 post on it. I'm still using the supplied Surly seatpost clamp that came with my frame, and I did have to tighten it more than "normal" to keep the post from slipping. But the bike is a couple years old now with thousands of miles on it, and there hasn't been an issue with the clamp other than when I was setting the seatpost height I had to tighten the bolt more than I would have expected. The stock seatposts on the complete LHT's are generic (probably Kalloy) 27.2's, and we find the same issue when using these. It's not a big deal, but I remember breaking a bolt once in setting one up. I can see why the Salsa clamp would be helpful, I once had a mountain bike that had a seatpost that tended to slip, the Salsa Liplock clamp solved the problem .

Does the Constrictor's collar lip contact the seatpost before the wider, lower section of the collar comes in full contact with the seattube?

-Kurt

I also have a Cross Check with the stock Surly clamp and no problems.

Kurt - now that you mention it, there may be some of that issue....I honestly didn't check that too closely. I just assumed that the seat tube was constructed with the internal diameter too large and that the seat post just didn't mesh well with it. After using the Salsa, it appears that I was completely wrong and that the stock clamp just didn't cut the mustard.