Best size/running -v - riding

Chipping in with some hard scientific data on these two recent threads…

I just put a trip computer on the 24. First proper ride today. I make no claims to be an expert, but the figures are a guide.

After 15 minutes I’d done 1.91 miles riding fast on a level but ‘cross country’ route. Top recorded speed 13 mph.

After 30 minutes of the same sort of riding, I’d done 3.96 miles.

After 30 minutes, I slowed down a bit, did some more difficult terrain, and spent a few minutes practising idling and reversing.

After 60 minutes, I’d done 6.95 miles (having ridden for 57:44 of those 60 minutes).

Top speed overall, still 13 mph.

So that suggests a 24 (with 102 mm cranks) ridden by a reasonably experienced reasonably fit rider, and with no substantial hills, is good for between 7 mph and 8 mph if ridden with enthusiasm on mixed terrain, and ‘revs out’ around 13 mph.
(I make that an attractive candidate for the ‘If I had only one unicycle…’ debate.)

And comparing it with running? I was never a good runner, but I used to aim for sub 8 minute miles on a treadmill, and got down to 7:03 from a standing start once. That is, I could hold 8mph for a couple of miles. I could probably ‘run out’ at about 13 mph too. (All this on a machine, with no wind resistance.) So, for up to 2 miles, I’d guess the speed comparison of me running and me riding a 24 produces an uncanny similarity.

The difference is that after running 2 miles, I never had the stamina to do 5 more miles and some running on the spot! So the uni is similar in performance, but much less exhausting, so more efficient.

cranks (was Best size /running -v - riding)

Thanks for the distances and times - I use the speedo as an odometer (I just bought the cheap version and put them on all my uni’s so I can track overall distance and time).

Can you give me some details on your cranks, my local bike shop will order some for me if I can give them some details (I’m in Melbourne, Australia so it works out much easier and cheaper to rely on the established infrastructure where possible).


Phil from melbourne

My 102 mm cranks were bought from

Look on the website and you will see Cranks, standard Replacement in various sizes including (from memory) 102, 110, 125 and 150 mm. The prices are reasonable (7 Pounds Sterling) and I guess Roger would despatch to anywhere in the world. For a beer, he might deliver them to you.:wink:

They’re not beautifully sculpted or anything, but they are solid and reliable. The black ones are a similar price and a bit smarter, but I think only the chrome ones go down to 102mm.

Roger says 89 mm cranks will be in from early December. :smiley: