Ensuring wheel size and sensor location for Cateye

[ddublu]

Picked up a Cateye wireless and installed yesterday. The tire size is in between the last two 29" sizes. I took the average and used that. Is that sufficient and how low or high on the wheel does the sensor need to be to work properly? I use Map My Ride on my iPhone and it showed the mileage to be more on the Cateye than the app. It also seems that the speeds shown are slightly faster than I'm really going?

My tires are the Geax AKA at 29" x 2.2. (I could use new tires as I am seeing slippage on roots and rocks in only my 3rd day on them).

[shiggy]

Picked up a Cateye wireless and installed yesterday. The tire size is in between the last two 29" sizes. I took the average and used that. Is that sufficient and how low or high on the wheel does the sensor need to be to work properly? I use Map My Ride on my iPhone and it showed the mileage to be more on the Cateye than the app. It also seems that the speeds shown are slightly faster than I'm really going?

My tires are the Geax AKA at 29" x 2.2. (I could use new tires as I am seeing slippage on roots and rocks in only my 3rd day on them).

Do a rollout for calibration. It is the only way to be accurate.

[ddublu]

Do a rollout for calibration. It is the only way to be accurate.

What do you mean? I compared it to GPS...is there something different to do?

[shiggy]

What do you mean? I compared it to GPS...is there something different to do?

It is in the manual, usually with the wheel size chart: "Measure wheel circumference (L) of your bike"

There are also many threads on this board about "rollout, calibration".