I replaced the battery on my little computer this morning, forgetting that this would erase not only the odometer reading (which wasn't that much, I only ran the thing for a week before the battery died!) but also the code that tells it what the wheel size is. So it defaulted back to 700 X 25C. I am running 26" wheels with 1-1/2" tires. How far off will my reading be, and is there a conversion factor I can use to find out how far I really rode today?

It's this computer:
http://www.filzer.com/products.php?id=4
User's manual: http://www.filzer.com/img/products/4-instructions1.pdf

I think the correct wheel factor is 2030... does that sound right?

I am running metric, by the way, except for tire size.

Thanks!