My unicycle collection arrived in this order: 20 inch, Pashley 26 MUni,
Coker, 24, 28. I know whereof I speak.
That is to say that the jump from a Pashley 26 to a Coker is perfectly
achievable. If you can freemount the 26 and ride it fast or slowly, and
turn both ways, then you can easily ride a Coker. It will take only
minutes to learn.
What to buy, then?
A 29 is only 3 inches bigger than a 26, meaning an increase in distance
per revolution of only 11%. If you ride the Pashley at 8 mph, then
you'll ride the 29 at 9 mph, all other things being equal.
That is to say that the small difference in wheel size will not make a
substantial difference in speed or distance capability.
But there are other considerations. A Coker is very specialised. It can
be hard to store and transport. It's great on rough ground, but a
handful in the woods or on narrow twisty tracks. It's a bomber, not a
fighter.
A 26 is great for MUni (although many prefer a 24 with a 3 inch tyre)
but most 26 inch tyres are knobbly and unsuitable for roads and firm
surfaces. It's a Land Rover Defender, not a Japanese SUV.
The 28 (or 29) is a versatile option. 700c is a common tyre size and
you can get knobblies, slicks, thin tyres and fat tyres.
Set up for off road use, the 29 will be faster than the 26, will roll
over obstacles better, but will be less manoeuvreable, and more of a
problem on hills.
Set up for road use, a 29 will be slower than a Coker, but more nimble,
less intimidating, and some would say safer.
If I only had one unicycle, it'd probably be the 28, with a selection of
tyres and cranks.
--
Mikefule - Roland Hope School of Unicycling
Everyone should be fatuous for 15 minutes.
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