Review and Giveaway: Bike2Power for the iPhone and Smartphone


Are you looking to generate power for your electrical device while on the bike?  Our friend @bobridesabike is here to give you one super detailed review of the Spin POWER 4 for the iPhone 4, made by Bike2Power. Oh, and be sure to make your way down to the bottom of his review for details on how you can win a Touring Edition SpinPOWER S1-R Universal Smartphone Bicycle Charger.

The Bike2Power Spin POWER 4 for iPhone Review

by Bob Avery

Have you ever toured on your bike?  Packed up gear for multiple days and planned on camping at night?  But you wanted to stay connected to the world, so you took your cell phone?  If so, did you encounter challenges to recharging your phone while on this adventure?  If you’ve ever ridden RAGBRAI (a week-long ride across Iowa), you know what I’m talking about.

As a cyclist, how do you monitor and map your rides?  Unless you’re a hardcore cyclist with specific piece of hardware, such as a Garmin, you might use one of the many cycling apps (such as Map My Ride, Strava, or Cyclemeter) available for smart phones.  But, if you’ve used them for rides much longer than a couple of hours, you’ll have noticed that these apps can be a complete battery suck.  The GPS that provides so much of the data output also drains the power from battery. So, if you’re planning a long ride, how do you take advantage of these apps?

Bike2Power brings back an old school solution to generating power for your electrical device.  In this case, for your smart phone.  There are two models available: the Spin POWER 1 for most smart phones and Spin POWER 4 for the iPhone 4.  (The Spin POWER 3 for the iPhone 3 has been discontinued.)  I have been given the opportunity to test the Spin POWER 4 for Loving the Bike.

The Bike2Power uses a dynamo system to generate power from the wheels, much like old school bike lights.

The dynamo, shown on the right, is mounted on the bike to rub against the wheel.  The resulting friction generates electricity to power the light.

Using this same principle, the Spin POWER devices generate the power to recharge your smart phones while on the road.  The kits include all required components: phone holder or cradle, mounting brackets, the dynamo, connector cables, USB charger, and a “cap” for the dynamo.  Bike2POWER claims that it’s easy to attach, simple to use, fits most bicycle frames and requires no retrofitting to your bike or spokes.  The only thing not included, besides your phone, is the USB cable for your phone to plug into your charger.  Since this is generally included with your phone when you buy it, you should already have one (or more!).

So how did they do?

I have used the Spin POWER 4 a few times and am impressed with it, over all.  It does its job of safely recharging your iPhone as you ride.  There are a couple of challenges to the unit, however.

Mounting: The charger and phone cradle mount to the handlebar: This is pretty easy to do.  The unit can accommodate handlebars up to one inch (1”) in diameter.  My handlebars, however, have padded tape with the brake cables underneath and was wider (in diameter) than the mounting bracket.  I ended up cutting the brake cable loose from under the bar tape in order to mount the unit.  In addition, the phone cradle and charging unit is rather large.  On my road bike, it takes up space where I might normally place my hands.  On a mountain bike, this would not be an issue.

The dynamo mounting bracket: Mounting it off the front fork was more challenging, in part because of the large size of the fork on my bike.  I was able to mount it two different ways – on the right side behind the fork and on the left in front of it.  The left side mount is where it is now.  The challenge for Bike2Power is that there is only one manufacturer of mounting brackets for the dynamo.  So they, and we, are stuck with what is available.

Here’s a look at the installation process:


The wire from the dynamo to the USB charging unit is long enough so that you can mount the dynamo in the rear on the seat stays or even chain stays, which are much smaller tubes.  I did not attempt this on this bike, but would mount it there on my other road bike (in part because it has an even larger fork).

The dynamo itself: I recommend using the cap for the dynamo, particularly with road bike tires (you know, the skinny ones!).  It is a hard rubber compound that easily fits on top of the dynamo.  This is a new feature that is being added to kits and will be available on “RAGBRAI edition” kits.  There is not a noticeable difference in the rate of charging, and it does reduce the white noise generated by the dynamo when engaged.

Be aware that without the cap, the teeth of the dynamo will adversely impact the life of the tire, especially the thin-walled road bike tires.  It may not be as much of an issue with thicker tires.

Also, be careful when mounting the dynamo, especially if you choose not to use the cap.  It is very important to make sure that the dynamo head is flat against the tire when it is engaged.  I tried different mount locations and for one had the dynamo mounted at an angle where the head was not flat against the tire.  As a result, the teeth of the dynamo head chewed up the sidewall of the tire.  You can see the result from the pictures linked to the end of this review.

Preparing to Use: If your phone is in a case, you will need to remove it in order to fit the phone in the cradle.  You then plug the USB cable into the phone and the charger unit.  Be sure to have some twist ties to tie up the extra length of wire from the phone.  (If you have an extra cable, you could tape it up and keep it in your saddle bag.)

The dynamo has a release tab to disengage the dynamo from the tire when the charger is not in use. This is a great feature as there is some white noise when the dynamo is in contact with the tire, as well as resistance.  And, as every cyclist knows, resistance means you have to put in greater effort.

Please note that the release tab for the dynamo is located on the inside of unit – between the dynamo and the wheel.  You should only press it when you are at a stand still and never when you’re moving.  Perhaps this can be changed in the future.

Another issue to monitor is the contact between the dynamo and the tire.  Be sure that the top of the dynamo is spinning constantly when in motion.  If it spins only intermittently or not at all, you will have contact and will not be charging your phone.  If, over time with uses, the dynamo doesn’t come into full contact with the wheel, you will need to readjust the mounting bracket angle.

Use:  On a 40 minute ride with the Cyclemeter app open and running, the Spin POWER increased the charge on my phone +16% (from 51% to 67%).  At that rate, you can expect to go from dead to fully charged in about four hours.

You should note that the Spin POWER is not water proof.  If you are riding in the rain, you will a) not want to connect the phone and b) wait until the charger is completely dry to use it.

Photos: On Flikr, here:

Retail Price: $79.95


While there are tweaks that can be made to improve this product further, I feel that the Spin POWER 4 is a great product for keeping your phone powered on the road. I will be taking one with me on RAGBRAI this summer so I can stay connected all week long.




For more information, see:

Enter to WIN a SpinPOWER S1-R Universal Smartphone Bicycle Charger:

This contest is now closed.  Congratulations to Antoine Wright who wins a SpinPOWER S1-R charger from Bike2Power.  Thanks to all of you who entered, and of course a huge thanks to Bob Avery for putting this together and to Bike2Power for supplying the products and being so cool to work with.

Get in to win either a Touring Edition SpinPOWER S1-R Universal Smartphone Bicycle Charger (Retails for $84.95).  To enter, leave a comment below telling us why you’d like to have one of these Bike2Power kits.  That’s it.  Get your comments in by this Friday the 27th at Noon EST and we’ll announce the winner soon after.

Bike2Power requires the winner to be located in North America.

Enjoy Your Ride

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