Just received two of these. Initial impression is these look really nice. Well built, clean lines, easy adjustment by hand with the option to use a hex wrench if you want. I wish they offered black and/or dark green as color options, but a little paint will make up for that.
they need to make a 25.4 double bolt quick release clamp
The current clamps do work for 25.4 post in a Nimbus Oracle frame, and also work for KH frames (the tubing is a little thicker on the Nimbus frame).
They should be referred to by external diameter the post diameter has nothing to do with the external seat tube diameter depending on the tube wall thickness (as the Oracle frames demonstrate).
These are 31.8mm clamps
If a clamp has a large gap and enough thread on the bolts/levers you can use them on smaller frames, but I would have thought it this new clamp had that ability UDC would have stated it.
I agree it bothers me to, but some people just get confused!
Ok, so enough ice has melted to do some riding in Missoula. How do the clamps work?
Yep, clear enough to avoid most of the ice, but still enough ice to keep it interesting if you want (which I do :)). I’ll admit I was a bit nervous yesterday - the last time I had ridden on ice I broke my leg. But I still got in good rides yesterday and today, and my confidence came back pretty quickly.
The Nimbus clamp is great. Less movement of my seat with very long handlebar in hard UPD’s than with a standard 2 bolt clamp. And waaay easier to set up. The quick release handles are nowhere near my legs, can’t imagine it would cause interference except possibly for freestyle/street tricks riding.
The only downsides are the confusion over the sizing and the colors. Works well, seems to be well made, and excellent value compared to high quality single quick release clamps such as the Salsa.
It is interesting you mention seat movement as I use lightweight Ali single bolt clamps just nipped up and don’t have any saddle movement yet my chum with the same clamps cranked right up has massive seat movement issues. Mush be something to do with more upper body movement? I slog it up the hills and tug my handle like nobodys business when needed but I think I ride naturally straighter / have better balance as he struggles with crowning and pulling to the side.
Shame they don’t come in anodised colours not powder coat
I have no seat movement whatsoever while riding. I only occasionally get some seat movement when I really smash the unicycle into the ground, with my long handle adding leverage to turn the seatpost.
Ahh, that’s better.
On my Oracle, I was considering cutting mine in half. Just to be a weight weenie, simplify, and less neon green. Bad idea?
Unishark, those look way better! Spray painted?
why not get a reglular QR calmp?
Just using what I already have. Besides, if I cut it in half then I have 2 lightweight, QR clamps. 
Thanks. I just prep’d with steel wool to rough up the original paint (not strip it), then hand painted with a few coats of acrylic craft paint. The purple is over original white, the green is over original neon green.
Re cutting: no reason why it wouldn’t work, but you’re not going to save that much weight, and personally I really like the extra clamping power. One of your half clamps would also lack a lip, so it would be a little less convenient to use.
Good points.
If I would get a single one I would get a hope or salsa
Unishark the paint looks great. Nice to see some more subtle hues.
I just got a new Nimbus Drak for my son. To my very pleasant surprise, it arrived with a double quick release clamp sized for the Nimbus steel frame and 25.4 seat post! 
I don’t see this part on the UDC websites yet, but it should be there soon.
BTW, the Drak also came with a Foss tube!
I got one of these on my nimbus 26 muni. I was pretty excited about it. Have to say, the one I got sucks. I can barely get it tight enough to not move when I UPD. Trying to get it tight enough is much harder than taking out a wrench and tightening the regular bolt style.
Not sure if there are good ones and bad ones out there. Definitely looks like I got a bad one.
The double quick came with my Oracle 29 frame that just became part of a custom build in the last few days. Kinda like a double Allen bolt clamp you need to ‘walk’ the top and bottom clamps down to get a really tight grip. Alternatively tightening one then the other…
I also bought a regular seat clamp just in case : ) this is a common issue. And I upd as much if not more than most so a sure seat clamp is a must.
pax