From the inventor of the slingshot bike comes a new bike that claims to help you climb hills faster and smooth out bumpy roads and trails. Here is an image of the original Slingshot bike from 1992.
Slingshot bikes used a mid-frame suspension system. The down tube was replaced with a steel cable suspended from a spring. There is a hinge on the top tube right in front of the seat tube. The idea is to use the spring and cable system to return the energy lost during the pedal stroke and also to smooth out bumpy terrain.
Seen at the CABDA expo on February 14th, is a new bike from the inventor of the Slingshot. The flat-barred Alter Cycles commuter has an interchangeable down tube to vary the flex.
All Alter Cycles are designed and built with Active Frame Construction which consists of two key components: (1) A patent pending top tube that is specially shaped to promote vertical flex while minimizing horizontal movement. (2) A patented arc shaped down-tube (Rider Fit Tube). These two components work together to allow the bike’s frame to extend when you encounter road bumps or pedal hard.
Alter Cycles claim this has 3 key benefits:
- Comfort: The flexing of the down-tube absorbs road bumps providing a smoother ride.
- Performance: It makes pedaling easier and more efficient by lengthening the power stroke, storing energy during the down stroke and releasing that energy at the bottom of the pedal stroke. When the energy is released, it reduces or eliminates the dead spot in your pedal stroke for a more even distribution of power. The result: pedaling is easier and more efficient, allowing you to accelerate faster and climb hills in higher gears.
- The flexing action allows your tires to seek and adjust to different levels, providing more constant contact with the ride surface and better handling.
While the bike is only available in three sizes, small, medium and large to fit almost anyone. You are able to customize your bike for smoothness and increased performance by choosing a Rider Fit Tube that matches your weight and desired ride. Their Rider Fit Tubes are made in the U.S. of HS90 spring steel tubing and are available in multiple levels of flexibility, and seven colors. Alter Cycles can be tuned to the weight of the rider, road conditions.
We were able to test ride one of their commuter bikes at the CABDA show and it does have a nice feel over bumps and the spring does seem to help propel the bike forward.
Certainly interesting technology! It will be interesting to see if they apply this tech to a road bike or CycloCross bike in the future. Would you consider this bike as your next around town commuter bike?