Hello from the Founder of ShareRoller. I only recently discovered some comments here on our product, and seeing that it is being compared to the Add-e / Go-e variations of friction drive, I wanted to clarify some differences between the products. I hope the points below are helpful, and I'm so sorry I'm not able to write this in German (and I figured Google Translate would probably do a bad job of converting my English). Happy to answer any questions you may have. Oh, and our Indiegogo campaign ends in two more days fyi!
Thanks,
Jeff
www.shareroller.com
https://www.indiegogo.com/projects/shareroller-add-on-e-power-for-bikes-scooters#/
A few key points to consider when comparing ShareRoller to Add-e/Go-e:
- ShareRoller can also power kick scooters as well as tens of thousands of bike share bikes in 15 cities worldwide. This is a huge increase in versatility, and once you try a powered kick scooter you'll wonder how you survived without one. And of course if you live in a city with compatible bikeshare it's an enormous plus.
- ShareRoller is a single, small self-contained package when removed, making it much easier to carry with you into an office or restaurant for example, or in a backpack to keep with you in case you get tired while riding and want to add assist. Plus the retracting motor assembly keeps the possibly dirty motor covered and protected when not in use.
- ShareRoller has a more advanced traction system: Add-e/Go-e use sandpaper/griptape in order to grip in the wet. This is an old-fashioned approach, and dramatically increases tire wear. Plus, the sandpaper/griptape wear out and need to be replaced. ShareRoller instead uses a custom treaded urethane belt (that lasts the life of the motor) combined with it's RainLock variable pressure system, to work well in the rain without significantly increasing tire wear.
- While Add/Go-e's mounting location under the bottom bracket is less visually obvious, it has a lot of negatives for an outrunner friction drive motor. First off, the motor is vulnerable to striking things you might ride over. Second, it will get pelted by dirt, mud, rocks, and debris kicked off by the front wheel. And while these motors can be cleaned, they don't like to be run with dirt, grit, and other junk on and inside them. So not really an optimal spot to put a motor.
- ShareRoller has three modes of operation instead of one (or two), including standard variable throttle, a unique 'TailWind' cruise-control system that doesn't require pedelec sensors, and a full pedelec setup for those that prefer that method. And in addition to smartphone integration, ShareRoller also offers a wireless throttle module which allows you to control all three modes of operation without needing a phone. It looks like Add/Go-e offer just standard pedelec operation, and only a smartphone app to change settings.
- ShareRoller offers built-in bright headlights and tail-lights, as well as a built-in USB charger.
- ShareRoller's quick-release split battery packs are unique in that they allow you to have a large capacity battery while still being able to meet the FAA and IATA carry-on Lithium battery limits.
- Finally, Add/Go-e use the common 'swing-to-engage' method of friction drive, which while having the advantage of zero-drag when not in use, makes for 'jerky' motor engagement, as large RPM surges are needed to swing the motor into the tire, which then 'bites' when it hits the tire. This also adds to tire wear, as the motor is spinning faster than the wheel when it engages. ShareRoller offers this same 'Freewheel' option for those that use the motor infrequently and prioritize zero-drag freewheel, but also offers a separate 'Continuous' engagement mode where the motor is always engaged with the tire, for smoother operation when using the throttle often, or when riding in TailWind mode. For many people this is a better solution.
- Steering impact is barely noticeable, and no different than having a handlebar mounted basket/rack, which are quite common on many bikes. Plus the weight of the ShareRoller (4.5-7.25lbs) is less than what is commonly put in front racks.
So there are a lot of reasons why the ShareRoller system would be preferred by many riders, but of course each person has their own set of priorities when choosing a friction-drive system.
Oh, and I forgot to add that for those who want to keep weight over their front wheel to an absolute minimum (say for heavy off-road mountain biking) we have a solution in the works that will enable the batteries to be mounted on the frame. Then the weight over the front wheel will be less than 2lbs/1kg.
