Well. That sucks.

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I recently got me a brandy new road bike. A yellow one for those who want to know what it is. And what's the first thing I bought to go along with my new toy ?

A brandy new cyclometer. Yep. Wireless no less.

I hook it up. Follow all the instructions in the manual like the good little boy I am, and set off on my usual daily ride. A tad over 16 miles.

I arrive home safe and sound and...what's this ?? My brandy new cyclometer only reads 14.2 miles. Hmmmmm

I triple check the settings in the manual and all seems ok. But something is seriously wrong here. I take both bikes to the nearest school that has a 1/4 mile track and do a little test.

Oh my.

Seems all the mileage I recorded on my mtn bike the last 10 months is over by at least 10%.

Which kills the 100 mile week I thought I finally did just last week.

Damn. Now I know why I started drinking. Quick. Someone remind me why I quit.

:D

bah, it's not about mileage, its about fitness. If ya feel good, yuor doin fine, it shouldn't be about a number.

Damn. Now I know why I started drinking. Quick. Someone remind me why I quit.

:D
You quit so you could get your bike computer settings accurate, remember?

If you knew you were at 90 miles you'd have had an easy time knocking off those last 10 to complete 100 anyway.

bah, it's not about mileage, its about fitness. If ya feel good, yuor doin fine, it shouldn't be about a number.Yep. Totally agree. Actually laughed about it when I realized my mistake.

It ain't about the mileage. In the last 10 months I've lost 40 pounds and haven't been in this kind of shape since my late 20's.

That said: I still want my first 100 mile week. :D

Yep. Totally agree. Actually laughed about it when I realized my mistake.

It ain't about the mileage. In the last 10 months I've lost 40 pounds and haven't been in this kind of shape since my late 20's.

That said: I still want my first 100 mile week. :D No better time to get it than this week. Go getter done!:D

you do realize that the wheel size for a road and mtn bike require different settings, right? i assume you do but just wanted to check. ;)

Its not the miles you ride, its the ride In the miles.:D

you do realize that the wheel size for a road and mtn bike require different settings, right? i assume you do but just wanted to check. ;)Yep. I ain't that stupid. I hope not anyway. :D

I hosed the setting when I took off the knobby tires and threw slicks on the mtn bike. I used the setting for 26x1.9 instead of 26x1.5.

Good timing for this anyway. I've actually taken advice I've seen in a few places and I mostly now go by time instead of distance. I still record mileage but don't really worry about it. It just became a problem because the 2 bikes were different.

That's not so bad... My ergomo pro distance does not match the Polar S720i distance I get when riding my CF Cervelo Soloist. And this is an expensive $1650 powermeter!

That's not so bad... My ergomo pro distance does not match the Polar S720i distance I get when riding my CF Cervelo Soloist. And this is an expensive $1650 powermeter!OK.....now that would make me start drinking again. ;)

Yep. Totally agree. Actually laughed about it when I realized my mistake.

It ain't about the mileage. In the last 10 months I've lost 40 pounds and haven't been in this kind of shape since my late 20's.

That said: I still want my first 100 mile week. :D
That sounds like reason enough to celebrate with a few beers!!!;)

Yep. I ain't that stupid. I hope not anyway. :D

I hosed the setting when I took off the knobby tires and threw slicks on the mtn bike. I used the setting for 26x1.9 instead of 26x1.5.
Most probably that is your problem. Do not use the setting in the manual. Inflate your tires to your usual riding pressure, mark the ground for the starting point, get on the bike, and roll it until you have made a full wheel revolution. Then measure that distance and use that for your wheel settings, and you will probably get a much more accurate reading on your odometer.

Most probably that is your problem. Do not use the setting in the manual. Inflate your tires to your usual riding pressure, mark the ground for the starting point, get on the bike, and roll it until you have made a full wheel revolution. Then measure that distance and use that for your wheel settings, and you will probably get a much more accurate reading on your odometer.

Yep! That's how you gotta do it. The manual just gives you some generic "700 x 23C" number (for expample) and the fact is there's a lot of variation in the circumference of all of the various 700c X 23mm tires. If you just plug-in the number in the manual, expect "approximate" readings form your computer. I recently set-up a Cateye wireless computer and the number the manual gave for the circumference of a 700 X 35C tire was about 30mm less than the actual measured circumference (with me on the bike).

Yep! That's how you gotta do it. The manual just gives you some generic "700 x 23C" number (for expample) and the fact is there's a lot of variation in the circumference of all of the various 700c X 23mm tires. If you just plug-in the number in the manual, expect "approximate" readings form your computer. I recently set-up a Cateye wireless computer and the number the manual gave for the circumference of a 700 X 35C tire was about 30mm less than the actual measured circumference (with me on the bike).For my the one I bought for my road bike(cheapo Bell cyclometer) it gave a generic number for all 700c tires. No mention of different sizes within that range. I used a chart from Sheldon Browns site to get a useful number for 23mm.

Approximate works for me. Drove a car thru my usual route and the numbers are all close enough now. I just wanted both bikes to read the same. Having one say 16 and the other say 14.2 was just too much of a difference.

Yep! That's how you gotta do it. The manual just gives you some generic "700 x 23C" number (for expample) and the fact is there's a lot of variation in the circumference of all of the various 700c X 23mm tires. If you just plug-in the number in the manual, expect "approximate" readings form your computer. I recently set-up a Cateye wireless computer and the number the manual gave for the circumference of a 700 X 35C tire was about 30mm less than the actual measured circumference (with me on the bike).I'll third that. Having used different computers and having set up computers on my parents' bikes (all different), they all give different readings that are not even close. Gotta get on the bike and measure a revolution. I guess I am just anal in that I want my computers to read as accurate as possible. Must admit a Cateye I had on my road bike that I now have on my mtn. bike is the most accurate.

My edge 205 reads less than my cateye. :)
C'est la vie.

I trust whichever device shows the fastest speed and the longest distance!