You saw them down to size, drill holes in them, whittle them and put them into a basic bike shape.
Ask a cycling buddy to help, book it in for a service at your local bike shop, or find a tutorial on YouTube – basic bike maintenance is easy, even for total beginners.
Instruction with real bikes, whether in a basic safety class on a closed course or a push-it-to-the-limits racetrack school, is a better way to advance, but this can overwhelm students who prefer to work at their own pace.
Their vehicles look like the love child of a basic road bike and an Apollo-era Atlas rocket.
"Just the basic bike is so hard to beat," said Steve Hed, a wheel designer and the owner of Hed Cycling Products in Shoreview, Minn., who has fitted wheels for the likes of Lance Armstrong.
Such basic bikes are used in cities to reduce auto use, and messengers and other urban warriors swear by them.
Froome, who learned to speak Swahili and a little Kikuyu (a regional language), was included by Kinjah in excursions with much-older native Kenyan riders on basic bikes through the dusty rural highlands near Nairobi.
The Hero Splendor, a basic, fuel-efficient 100cc bike, is the world's best-selling two-wheeler by dint of its popularity in India.
A basic cross-country mountain bike tire is around two inches wide, but even summer tires are getting bigger, with an emerging "semi-fat" category at around 3 inches, while most winter fat bikes are in the 4-5 inch range.
