Largest Wheel Possible

I was wondering how big of wheel I could get, I am 5’ 10" With fairly long legs and want to go as fast as possible. I know about the 36" ones but what about the size that the guy used to do the fastests mile. I already got a 4 minutes and 30 second mile on a 24 inch and want to go faster.

get a 36"

Im 4’ 11" and can ride one.

thats my point I want one bigger then a 36" to go even faster

Nothing bigger than a 36" is made stock. There is a 48" on UDC ( but it is really uncomfortable, unstable, and not very strong at all. You will want a 36". If you are really set on going extremely fast, then you could get the Shlumpf geared hub and build a 36" around it. That will give you the gearing to go very fast and keep a smaller wheel diameter.

The down side to this is that you will easily break speeds of 20 MPH (I’m assuming that you are reasonable fit). Riding at speeds like this can be very dangerous. People have gotten hurt just on a regular 36". What I am saying is that if you are pedaling in low gear (1:1) at a comfortable pace, you might be traveling at 12 MPH. In high gear (1:1.5) riding at that same comfortable pace, you will be traveling at 18 MPH.

If you are going for pure speed (like on a mile record) you will be going as fast as possible the whole time. In low gear, riding as fast as you can, you might be traveling at 20 MPH. In high gear, riding as fast as you can, you will be traveling at 30 MPH. Speeds in this range are extremely dangerous, as a crash could easily break an arm, give you bad road rash, or send you flying, causing you to hit your head. A whole bunch of other bad things could happen, and plenty of people have had bad accidents just from a regular non-geared 36".

Basically I’m telling you to re-think the safety aspect of riding at such high speeds.

He wants to hydroplane across water like I do.

1:5 Geared 36er with and endomorph tire.
+1 spare life.

24-26ers are good for short sprints. 36ers is the uni to continually go fast, and go long distance.

I would get a 36er in your situation, no gears (they can slip, and severely injure you at high speeds a Maximus described).

You can easily calculate the largest diameter wheel that you can fit. It is going to depend on crank length. It is also going to depend on the style of the frame. You can mount the seat directly to the crown (no seat tube or seat post). Some of the large big wheel unicycles mount the seat directly to the crown.

Take one of your existing unicycles and adjust the seat height as you would for a road unicycle. The seat height is going to be higher than what you would use for muni or trials.

Position a pedal in the lowest position. Measure from the pedal to the top of the seat. That gives you your base height measurement. From there you factor in desired crank length, seat thickness, seat tube length, and other necessary factors. With some basic math you can figure out the largest wheel diameter you can ride with a given crank length.

But the big wheel unicycles with the solid rubber wheelchair style tire are not good for general high speed cruising. The solid rubber tire is skinny and doesn’t absorb road bumps. You can’t go as fast with that kind of tire as you can with an air filled tire.

Geared unicycles are the way to go for speed. Consider a design like this. You can gear it to any effective wheel diameter that you think you can handle.

i think seb abrahams rode the worlds largest unicycle, using blocks under his feet so he could reach the pedals. not sure how big it was but theres a picture somewhere of it. also not sure if it was seb abrahams or not.

I came up with a a sweet idea making any whell diameter possible for anyone… It should work out…

even a kid with no arms or legs ! sweeeeet.

YAY!!! so now I can ride one??

Haha ok you have to be able to ride a regular unicycle…

wooden block on the peddles work fine, there cheep and easy, your gonna have to have a good idea to beat that.

but the bets of luck to yo mate :slight_smile:

bye bye x Dale

Would you want a solid tyre or pneumatic?? :smiley:

I want to say it was something crazy like 72".

It can be done. :smiley: :smiley:

thats the picture i was looking for !!

i’ve seen less dangerous things in my life, but not many. i wonder if he can free mount it - hah :stuck_out_tongue:

Apparently it’s a unicycle with a wheel diameter of 73 inches (185 cm) :astonished:

shooooowwweee!!!shoot thats one huge tire…

Agreed. Trying to ride that thing at 150 rpm would be taunting death - falling from 6 feet up at 35 mph. Yeehaw. :astonished: :astonished: :astonished:

Maybe someday me, owen, tomtrevor, mills mobile, tobboganist and the rest should team up and make our ultimate speed freak machine. :smiley: :smiley: