I have a cheap computer but it works fine. I've been using wheel factors from the sheet that came with it. I tried the roll out thing but that got way to compliocated and confusing and then converting my measurements to a wheel factor rwally made it simpler to just use the sheet that came with the computer. And it was simple because what I rode was on the chart though the notes "wheel diameter" and "with tire" confused me.
bike with 27x1 1/4 I used 2155
bike with 700x28 I used 2136
now I have a bike with 700x23 and the shop gave me a factor of 2096 which doesn't sound right. according to the sheet that sounds like its for a smaller wheel like on an MTB or something.
this is what I have:
what factor do you use for your 700x23?