KH20 Flatland uni project


For quite a few months, Spencer and I have been working on various ideas to do with producing a KH flatland uni. Adrien Delecroix has also been testing and providing feedback.

The goal is not to repeat what’s out there or simply rebrand the KH20 as a flatland specific uni - I’m not just going to repaint the KH20 and call it something different. It also has to fit enough people’s riding styles worldwide to make it widely available - so it’s good to keep it simple and improve the most important components without making anything unnecessarily specialized.

IMO, the existing KH20 works well as a versatile trials/street/flatland uni, but there is room for improvement for rolling-oriented flatland - ie. for a lighter weight, smoother-rolling wheelset that bridges the gap between freestyle-oriented tricks and flatland style.

So far the most versatile setup seems to be the one that Spencer is riding:
KH20 longneck frame
110 mm Moment cranks with Rollo disks
New 20", 47 mm wide KH rim.
Maxxis Grifter 2.1" tire.

Attached is a photo.

This is the setup Spencer is using in his new vid.

In summary it uses all the same parts as an existing KH20, except for the new rim and tire. The nice thing about the Grifter/wide 20" rim combo is that it is lightweight and smooth rolling like a freestyle wheel - the Grifter weights less than half that of a CC tire - but the wide rim gives the same lateral stability as a trials wheel. It’s harder to flip, but there’s already the trials wheelset out there for that. Whether you’d prefer this setup or the standard 19" setup would depend on your riding style.

It would be great to get feedback from all of you as to whether you’d be interested in seeing this setup come out.

Thanks in advance for the comments!



Sounds like good news. Are you going to be changing the frame at all (Double Crown option maybe?) or is this basically a new wheel set? Another option to make sure is included is crank size; 110 mm seems a bit small for me (and I am sure others too). I personally find crank idling easier with a medium size crank so that the foot on the crank doesnt get in the way of the foot idling with the pedal. And I like to include flip trick into my flat which I am not sure how such a smaller crank would affect.

I am not sure if I would get this even if I had the money though because I ride a lot of street. But if ever I start riding a lot more flatland (and had money) I would be interested.

I did experiment with frames but the results (so far) were too close to the KH20 longneck to be worth producing. Keeping it with a KH20 longneck means that it’s fully compatible with a 19" wheelset, so you could switch out just the wheel to ride trials/street without having to necessarily get an entirely different uni. For dealers it also means they have to stock less stuff, which means there’s a better chance this could be made available worldwide.

Same goes for the cranks - there is too much diversity of opinion on this to have one “best” length. The 110’s seem good given that the rolling weight is so much less and that it’s aimed more towards a smoother rolling-oriented style than flips. Spencer also tested prototype 100 mm cranks but felt 110’s were a good setup. So 110’s could be spec’d standard with other lengths available upon request.


doesnt spencer break a lot of spokes on that? Atleast from when ive seen him a few times. (he broke like 4 or more spokes at mondo).

cool uni no doubt, and obviously good for flat.

good job kris and team!

I like the rim but, why it have machined walls?

Ouch :smiley:

Sounds good. But… I think moments need to be changed… Their too heavy. Has any thought at all been put into this?

I’d only buy one if the rules for flatland competitions were changed. If you can’t flip as well then you’d be at a disadvantage.

Maybe I’d get one for fun/pure flatland like Spencer.

Its basically a freestyle with a trials frame and cranks right?

Spoke breakage has been reduced by moving to 14g spokes (=thicker nipples) and with the new '09 Moment hub the flanges better support the spokes. That said, kicking spokes is always going to increase the chance of breakage.

No reason except that it’s a prototype.

The 110 Moments are currently lighter than the 125’s or 137’s with a wider, deeper cutaway. So are the 110/127 double holes, actually.

The wheel feels quite a bit more stable than a freestyle wheel, and the wider rim lets you drop the pressure so that you can get more bounce in the tire - a crossover between freestyle & flat. So you can flip it; you just have to be quicker, although smooth rolling and light weight are more of a strength than flips. Once Spencer sees this thread I’m sure he’ll have more comments on that.


Great idea Kris. Have you ever noticed that the unicyclist are the pickiest and hardest people to please. If it’s not the color of the frame its size or the tire. Kris, I’m sorry it’s so hard to please everyone.

No worries - I’m just glad I don’t make bikes! =)


I love this uni. Pretty much everyone who picks it up is amazed at how light it is.

For flatland I wouldn’t really want to ride anything else, it rolls so smooth and any trick where your foot is on the tire is easier and more comfortable.

I really like the maxxis grifter tire, but if anyone wanted something different there are hundreds of bmx tires to pick from. The grifter is nice because it is relatively big, really light and the tread pattern is good for gliding and stuff like that. My tire is a little bigger than in that photo because there was no air in the tire.

About flip tricks, you could still do them its just the cushion of the tire isn’t there anymore. I don’t practice flip tricks because I don’t think they fit in with the style of my riding but I can still doubleflip easily and I learned hick doubles at NAUCC really fast. The wheel actually flips really fast because there’s much less rotating weight. You can still do flip tricks with the uni, but it definitely isn’t a replacement for a street uni.

I’m sure quite a few people will prefer to ride a trials wheel just because it is more convenient to have one unicycle for everything, but if you’re really into flatland or freestyle, it’s beneficial to have something that is suited specifically to that style of riding.

I got some different spoke and that is mostly fixed. I still break some nipples every now and then when I land badly, but that happens on every wheel I ride. All of the spokes I’ve used in this wheel I’ve just bought from a bmx site, so it is kind of irrelevant :slight_smile:

I am very excited for a Kris Holm flatland unicycle! I agree with Any Terrain about the crank size. I think that consumers should be able to keep the option of being able to choose there crank size (110, 125, 137). Maybe some new colors? Single Crown unpainted?

Dont pull the 'ol “Once spencer gets here…” Line on us! :stuck_out_tongue:

haha. props to kris and spencer though. Sounds like its a good prototype.

I actually think its an awesome idea. It would really be nice to be able to see more people riding a uni like this to add a more freestyle feel to flatland. I agree that it would be good to have options on the crank size beacause everyone is different. But the whole idea seems to be pretty good so far. Keep up the good work.

I’m just throwing this out there but I personally like tubular cranks for flat rather that KH moments with rollos. Just because it feels more stable and it doesn’t hurt my feet as bad. This is just my opinion.

+1 Of course i’ve never tried out the rollo disc…

I like your idea BTW Kris.

+1 Of course I’ve never tried out rollo disc and there are already people who make tubular cranks…

I like the new uni idea BTW Kris.

looks cool Kris… +1 to the cranks option is well… I dont ride flat or freestyle but yea… having a crank option would be best.

Oh yeah I forgot to say though that I really like that idea. I rode spencers uni at naucc and I really liked it. I’m glad to hear the new idea!