I am setting up my computer on a new Roubaix Pro. It has tires that read 700x23/25c. What tire size should I set my computer at?
This is Spec's description:roadandtrail said:I am setting up my computer on a new Roubaix Pro. It has tires that read 700x23/25c. What tire size should I set my computer at?
Some people's experience may be different, but I've always had reasonably accurate mileage readings from simply using the tire size chart for the computer. This is for several different computers and various tires. Like, within one or two tenths in 10 miles and/or a very tiny percentage difference between my computer(s) and my Garmin (i.e. my daily commute - if garmin says 12.36, computer may say say 12.2 to 12.4). So, what I'm trying to say is depending on ones' tolerance for accuracy, that's what I'd try since it's easiest. Most likely plenty accurate.andulong said:The size listed on the tire does not mean a whole lot as far as setting up your computer accurately. I have seen HUGE variances from brand to brand. The most accurate way to set up the computer is by doing a roll out test to find the circumference then put your numbers into the computer..radius, diameter or circumference or whatever it may be based on your roll out.
You can also do this without someone else's help by riding thru a water puddle. Just measure from the front edge of the puddle to the front edge of the next water spot (one revolution later).Mr. Versatile said:step 1 pump your tires up the the pressure at which you normally ride.
step 2 go get a friend/wife to help you.
step 3 mark a fine line on the tire sidewall using a ballpoint pen or similar.
step 4 get on the bike and have your friend tell you when the mark is exactly straight down , closest to the pavement.
step 5 make a mark on the pavement that corresponds to the mark on the tire
step 6 "ride" the bike slowly along a wall (I use a garage wall) for exactly 1 revolution. you'll need your friend to tell you when this happens. try to keep the front wheel traveling in as straight a path as possible
step 7 mark the pavement as in step 5
step 8 carefully measure the distance between the two marks & convert to metric (centimeters)
step 9 set your computer to this number