I can go faster than I will ever want or need to go on my 20" wheel. I don’t see any reason to go any bigger.
a high psi tire will make a 20" wheel go close to the speeds you can get on a 24".What tire do you have?
You may just be a speedwuss too so…
On a hill by my house i did 17.9 on my 24" and 12.3 on a 20" (thats not 19", 19s go even slower)
Hes right!
I have a bmx style tire on mine and run it at a pretty high pressure. Landing jumps is a pain, but it’s a nice smooth ride.
I usually bail when I get to my top running speed; I don’t trust my riding skills enough to go at speeds where a crash could be painful.
After a certain point, from what i could tell its around 13-14 mph the riding gets much much earyer, you can practicaly put your arms down. It must have to do with the rotation speed and the size of the wheel it hits like a good gyro-scopic procession.
Theres a nice high psi 20" bc in the trading post cough
http://www.unicyclist.com/forums/showthread.php?t=48947
why wont it work well?
Edit: ok i see what spencer said
How well do Hops and Jumps hold up on BMX tyres?
Are they easy?
Are hops a lot easier on trials tyres?
Is a 2.1" tyre a good compromise?
Do you need a BMX hub?
What’s the standard(ish) price?
What’s good to look out for?
Will any hub do?
Ta, AndyC
There’s a maximum rate of speed a thing can go without and extra force.
If you through a penny off the tallest building in the US, its maximum speed isn’t even enough to kill a human, I’ve seen it tested. =p But if you through a bigger object, the velocity of it will be greater, increasing the speed, so it could kill a person down on the ground. This implies to rolling.
Find a hill to do tests on, a small wheel can only spin so fast on the hill before it reaches the max RPMs, you will accelerate faster but your speed wont be as high. Take a bigger wheel, like the 24inch, and there’s gonna be a higher RPM, more distance is covered with less revolutions of the wheel, and in turn, you’ll go faster, but with a slower acceleration.
Also the weight of the wheel will change it, how big of the person that is on the wheel will change it, really it all has to do with the forces being pushed on the object, and most likely, the bigger it is, the faster\more velocity it will have.
P.S. I’m not sure if i worded everything up there right, so it may not make since to you lol.
im little and lightweight, so would a 20" tire be better?
Just a heads up, I got a hub with a 14mm axel on ebay for about $4. It isn’t sealed but as long as you don’t mind riding an unsealsed hub, it is a great deal. I don’t know if there are any left but you may want to check on that before spending a lot of money.
wow ill look there
is it a shimono hub? ive seen it if it is.
[QUOTE=Jerrick]
There’s a maximum rate of speed a thing can go without and extra force.
If you through a penny off the tallest building in the US, its maximum speed isn’t even enough to kill a human, I’ve seen it tested. =p But if you through a bigger object, the velocity of it will be greater, increasing the speed, so it could kill a person down on the ground. This implies to rolling.
QUOTE]
Ever heard of all things fall at the same rate. It’s true. A penny would fall at the same rate as a baseball. (atleast in a vacume) A boling ball would deliver a more letal blow than a penny, but thats only because of weight. they would fall at the same speed.
Wouldn’t a bowling ball and a pennd have different terminal velocity and fall at different speeds?
ps. Can anyone answer my questions please? (#37)
On a bmx tire hops might be a little easier because it is lighter but the trials tire makes the landing smoother. I don’t think there is anything that you can do with a trials bc that you cannot do with a bmx just it goes smoother on the trials.
You need a hub with a 14mm axle, I don’t know much about bike hubs though.
Great, thanks Lil Dude!
I just wanted to check before I went ahead and put my money on the table.
Your a pal! 
A Bowling ball would beat the penny down to the ground because the penny is flat meaning it has more wind resistance and will go slower. But if the constest were between a tennis ball and a bowling ball it would be the same.
I think the hairs on the tennis ball would slow it down. Maybe a pool ball and a bowling ball
Tish
Good job George.
How about -"The bowling ball would beat the penny to the ground because it’s about x1000 as heavy!
It wouldn’t be the same between a tennis ball and a bowling ball. Saying that is just plain dumb.