K Tor Power Box Pedal Battery Charger for Cellphones and Other Gadgets

I have been interested in this for a while so i decided to bite the bullet and buy it. Its very simple to use but i recommend bolting it down like they say in the instructions, otherwise it moves/ tilst up. Much easier to pedal than use the smaller hand crank version.

The idea is a vast improvement over trying to crank 90 RPM with a hand held version. My arms would get so tired it was nearly impossible to keep going. The pedal version is definitely better because of the obviously stronger leg power. The one thing that I would say that would make this work so much better is the addition of a gear, so that you don't have to physically spin your pedals 90 rpm -- a gear that allows you to spin anything less, such as 45 or 60 rpm, while the gear transfers the speed to the charger so it turns 90 rpm would be a lot easier.

The reality is - spinning 90 rpm with your feet on the pedals takes a lot of energy and concentration, it's practically the equivalent of sprinting, and you can't do it "mindlessly", as soon as you think about anything else and try to let your body go on auto pilot, your legs slow down to just a little less than 90 rpm, and I presume that it just doesn't charge much or at all at that pace (I noticed my charging light wavering when I slowed a bit).

It's just hard to keep up a non-stop sprint pace for 10-15 minutes or more, and the actual resistance isn't that hard (way better than with your arms), it's just the speed is tough to keep up.

I assume that an extra gear to translate the speed would add a bit of size, weight, and cost, but I would pay it. It would make the whole thing much more effective.