This is a regular question, and you will find much advice by spending
some time searching the forum.
However, the answer is not a simple one. 24 or 26? That's like
asking, "Which is the best gear to use on my bicycle?"
The difference in "roll out" is 2/24 or 1/12 which is around 8%. That
means at a given rpm, you will go around 8% faster on a 26. That's
less than a mile an hour difference in most circumstances.
But there are other variables. The bigger wheel rolls over things
better, meaning it is less likely to get bogged down in undergrowth,
sand or mud. So you can not only go a bit faster, but you can keep
your speed up more eailiy, and the combined effect is to be quite a lot
faster over a journey.
On the other hand, if you want to hop, jump or drop, or if your style
of riding involves lots of slow manoeuvring, sharp turns and so on,
then the smaller wheel will be lighter, stronger and more
manoeuvreable. And with this style of riding, speed is not usually an
issue.
Then there are variables like crank length (at least as important as
wheel diameter for speed and hill climbing) and tyre section, profile
and tread.
The answer then is one of emphasis:
If your riding could be described as "vertical" then maybe a 24.
If your riding could be described as "horizontal" then maybe a 26 - or
even a 29.
26 is an easy size for tyres. Certainly over here, most mountain bikes
and hybrids have 26 inch wheels. 24 inch tyres are less common, in my
experience. That said, both sizes can be bought from the usual on line
unicycle suppliers.
--
Mikefule
Against stupidity the gods themselves struggle in vain.
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