Round Crown Aluminum Frame

I’m talking with a frame builder about making some round crown aluminum frames.

I need two things from you.

What is the max you would pay for such a frame? How many of you would really buy one if they are available?

I would pay up to $250 for a round crown frame that would fit a 26X3 Gazz, has machined 42mm bearing holders and includes Maura mounts.

edit $200 USD or $250 CAD whichever is more

I would probably pay a max of 50$ for a alu. frame.

250usd. I’m not sure I owuld get one though.

20inch frame.
but I would only buy it if it were lighter than a kh frame.
preferably longneck option cause I ride trials and the whole purpose of a round crown for me is to not bash my knees. the longneck would put the post clamp high enough to not hit body parts while riding.

Different frame sizes and neck lengths shouldn’t be a problem, but I will check. Magura mounts I know won’t be a problem.

Yeah, good point, if it’s heaveir than the kh, I will not go for it. If it’s not a longneck, I’m also not really interested.

If you could make a strong, light, longneck alu round crown I would be in.

cool. I’d def pay 200-250 (whatever really, as long as its not like a 450 dollar frame). Yeah, sounds great dude!

i’d maybe be interested… however i really prefer steel. if decent tubing is used, they could be lighter and stronger than aluminum

I may be interested. But I would use it for flat and street, so I need to know it will not brake where the crown meets the seat tube (when doing tricks like 270 unispins or others that put a lot of stress there.).

$175-225 US

EDIT: 20"
We could get the longneck any size right? I would want around 250.

you should make a longneck for definate, 42mm bearing caps for ISIS… umm… 27.4mm so you can put koxx one seatpost and clamp on it.
Price… around £70 (not sure what that is in $'s)

Has he built any unicycles before, or just bike forks - worth knowing, as bike forks take quite different stresses to unicycles, so it might take a few more prototypes if he doesn’t know about unicycles?

Is there a guarantee?


He does actual bike frames. It’s still up in the air, just gauging interest right now.

Latest Work:

A price simular to the KH frames would be fair.

I wouldn’t pay more than for a KH frame…

Why do people suddenly like round crown frames again? I must have missed that memo.

I’d be wary of buying a custom built in the USA frame that cost less than the KH. Bearing in mind that pretty much every other custom built frame has cost more like $500, it’d suggest some shortcuts being taken in the process somewhere. Unless it’s being built just for fun and the guy isn’t charging for his time.

I mean the guy above who priced up the material has costed it at $90 in materials + machining alone, although there are some pretty random numbers in there - like $20 for machining a set of bearing holders sounds pretty cheap - given a mass produced commercial pair will cost you $40, I’d bet the real cost would be easily twice that. If he’s doing it well he has to factor in the cost of a few prototypes as he’s never built a unicycle before, the cost of his time building them, the cost of guaranteeing them, and a profit.


That’s the cost for half a bearing holder, and mass produced in Taiwan out of steel, which you obviously can’t use for the top bit of a bearing holder on an aluminium frame. So $24 to get a mass produced one from Taiwan out of a cheaper material. If you buy the ones mass produced in Taiwan out of aluminium, the cost is $40 a set (KH ones). You’d usually expect a custom build to be more expensive than the cost of buying them.


Those are CrMO and not alluminum, I don’t think those 2 will weld together :roll_eyes:

How much market is there for a frame only?

Granted, I’m looking to upgrade my 24" Nimbus II, but that’s only because it’s the old one which is too narrow for a 3" tire; I also want brake mounts.

The new Nimbus muni frame is ~$45, KH is $200, so if you build a round alumium model that is equivallent to KH, I’d go $100.

The weight difference in a 24" frame, between a KH and Nimbus, is around 6 ounces. You could save that by changing tires, a lighter tube, lighter cranks/pedals, etc…

If you want to sell a frame, use titanium, it’s what people want and no one has one for sale!