stupid, shameful Shimano Flightdeck question

[Old Timer]

Yeah, I'm finally admitting it. I have no idea where the wheel
measurement "650 x 1.75" or x 1.5 or x 1.25, etc.. comes from. Sure, I
got the first part, 650 or 700, but for the life of me I can't figure
it out nor is it in the manual.

I've always done the rollout method instead, but not knowing is
plaguing me. I feel such shame.

Help please. Thx.

 

[John Park]

"Old Timer" <[email protected]> wrote in message
news:[email protected]...
> Yeah, I'm finally admitting it. I have no idea where the wheel
> measurement "650 x 1.75" or x 1.5 or x 1.25, etc.. comes from. Sure, I
> got the first part, 650 or 700, but for the life of me I can't figure
> it out nor is it in the manual.
>
> I've always done the rollout method instead, but not knowing is
> plaguing me. I feel such shame.
>
> Help please. Thx.

The rollout method for determining tire diameter seems to be the most
accurate method of setting up your computer, but as to the markings on tires
and such.....the first number is the diameter and the second number is the
width. 650 is metric and the 1.75 is inches. For more all the facts, check
out Sheldon Brown's website at http://www.sheldonbrown.com/tire-sizing.html

Hope this helps,

John P.