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Carol Young
Reviewed in the United States on March 10, 2025
It was great
joshnjessb
Reviewed in the United States on July 27, 2024
Double clamp allow more clamping all over. I had to fabricate this to work on a built in seat clamp on the frame. I cut out the built in clamp and fabricating this on to clap over and then onto the seat post. very happy with the outcome and saved me from having to do something more drastic.
DPatel
Reviewed in the United States on August 5, 2023
Perfect fit for 27.2 mm post. It solved the problem
Casey W.
Reviewed in the United States on December 26, 2023
Had this seat post clamp for maybe a year, very light use. Just noticed today that it cracked. Looks like a pretty obvious design flaw. Bummed because I like the design.
Susan K. Miller
Reviewed in the United States on October 18, 2023
Perfect fit for my build. The clamp does securely support a carbon seat post as described. It is not bulky and is cosmetically appealing. Great value.
Charles Carr
Reviewed in the United States on January 6, 2023
It's a good quality clamp. I'd like to see the transition area between the two sizes be a little thicker, for a hefty guy such as myself. But so far, it's getting the job done, so we'll see about longevity.
Justin Sison
Reviewed in the United States on September 9, 2022
Every Brompton owner has experienced a slipping seatpost, probably on their first day, and they'll find three solutions online:(1) Clean the seatpost and try to avoid touching it at all from now on, lest your filthy, oily palms make the seatpost slip again.(2) Tighten the nut. But not too much, or you risk damaging the frame, which means buying new bike.(3) Buy a secondary clamp and use a rat tail file to remove the inner lip to fit the seatpost.Well, folks, I'm gonna tell you that (1) cleaning doesn't make a bit of difference, (2) tightening the nut will only work up until a certain point when you'll have to tighten even more, and (3) the secondary clamp is actually a good idea, but it has to be this one; there's no stupid inner lip to carve away at!Right away you have two clamps instead of one, even if only the smaller clamp on top is doing all the work. Probably better that the smaller clamp is a little higher up from the bottom of the seatpost anyway. The clamp uses a 5 mm hex wrench instead of a latch, so you can really go to town on tightening the clamps against the steel seatpost, though I might go easy if you're using a titanium seatpost.What really sells this clamp is that it allows me to have the nut on the Brompton back down to factory tightness, or maybe even a little less, so the frame is never in any danger of overtightening. Whereas before with the Brompton quick-release clamp alone I accepted there would be slippage no matter what, I'm now confident this is no longer an issue with the additional clamp.The only downside to this clamp is you'll probably want to bring a spare 5 mm hex wrench with you everywhere you go from now on, and completely folding/unfolding the bike will now take another 30 seconds. But if the tradeoff is no more worrying about seatpost slippage or overtightening (and if I'm being hopeful, no more replacing the inner sleeve every year), I'd say that's more than fair. And hey, accessorizing is fun; get yourself a bag for your bike!And yes, both the Amazon listing and even the product itself say "31.6" and Brompton says its seatpost diameter is 31.8, but as you can see in the included photo, this clamp will fit your Brompton seatpost just fine. Just be sure you get the right size! (31.6/34.9)
gotbeef
Reviewed in the United States on January 23, 2021
This is an awesome clamp. I have an aluminum frame bike with a carbon seatpost and no matter what I tried the seatpost would slip (tried stainless shims, grip paste, rubber sheet, none worked). I also didn't want to over torque the fastener and crack the seatpost. This dual clamp provides vastly improved clamping without ever coming close to over torquing the bolt. I would buy more if I had more bikes.
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