The Evolution of the Single Cam
“Darton’s Maverick CPS may well represent the next generation of
Norb Mullaney, Bowhunting World,
First Graham introduced the single-cam of the ’70s and ’80s. Next Matthews introduced the single-cam of the ’90s.
And now Darton introduces the Single-Cam of the next millennium!
Stronger. Smarter. Faster. Evolution has a way of eliminating the weak and leaving only the strong to survive. When something newer and better comes along, the old gets pushed aside. The Mathews design replaced the older DynaBow because it was superior to it in terms of both speed and accuracy. Darton’s Controlled Power System (CPS) is already being recognized as having as many advantages over the conventional single-cam designs as they did over the DyanBow. Norb Mullaney, in the December 1996 issue of Bowhunting World, wrote the following about the Darton CPS bow
“Darton’s CPS bow may be classified as a single-cam bow because it offers the benefits of the single-cam system with both limbs being loaded by a single cam. It may not look that way, but that is what actually happens. This is what eliminates the need to synchronize two cams. The Control Wheel acts only to balance the wrapping and unwrapping of the bowstring, controlling the travel path of the nocking point. Thus, the CPS goes beyond the normal single-cam system with controlled nocking point travel, even tiller, a module system for draw-length change, and a standard-length bowstring.
I view the CPS as a hybrid, certainly not a two-cam compound, but decidedly more than a single-cam bow. No matter what you want to call it, however, the CPS is truly a remarkable development. It is a concept that is the result of research and refinement in the science of bow operation, and also in the art of bow design to capitalize on the broadened knowledge obtained. Archers who wan to ‘set it and forget it’ can come very close to doing just that with a bow that incorporates this unique rigging system. Beyond that, they will have a compound that will delight them with their shooting capabilities.”
Darton’s CPS doesn’t look like any other single-cam system because it ISN’T just another single-cam system. As explained above, it still uses just one cam to flex both limbs and has even tiller, but that’s where the similarities stop. The CPS offers several significant advantages that old conventional single-cams just can’t. It’s true that conventional single-cam designs are becoming more advanced every year, but even their best designs have limitations we’ve overcome. The following page lists just some of the advantages of the CPS designs.
1 Level nock travel.
Much has been made of this particular advantage because of the obvious correlation between nock travel and arrow flight. The CPS (Controlled Power System) system consistently provides better downrange arrow speed potential due to its more stable launch and better arrow flight.
2 Greater Speed Potential.
Design limitations of old, conventional single-cam systems place limits on potential speed by compromising stored energy trying to achieve acceptable nock travel and arrow flight. The CPS, however, is not handicapped by these limitations. As you can see in the adjacent force draw curve, the CPS equipped Maverick displays a smooth initial draw (gentle upward curve) and a comfortable let-down (smooth sloping downward curve) while still building incredible stored energy (long, flat plateau in the middle of the draw). Additional speed can be achieved with light arrows by using speed tuning nock sets on the bowstring - a standard feature on some models.
3. Level nock travel throughout adjustable draw length range.
The Controlled Power System also features another patent-pending innovation on some models: adjustable draw lengths. While it’s true that most every bow today has some method of adjusting the draw length, the CPS can be adjusted in approximately 3/8” increments over each module’s 1” to 2” range. And the best part? The module’s design maintains the optimum level nock travel path regardless of the draw length adjustment you choose.
4. Conventional length strings and cables.
Old, conventional single-cam systems have a bowstring that’s twice as long as normal, which leads to twice as much stretch. If the nock point were in the middle of this length, the effects of the excessive stretch would be minimized. But since the nock placement is closer to the end, most of the stretch occurs above the nock point and moves it downward. The result is a need for constant readjustment for proper tune and arrow flight. The CPS has a nock point midway along a conventional length string and so does not need excessive maintenance.
Figure 1. Darton Maverick - Indicated that even with bowstring and control cable each stretching 1/4”, there is a negligible effect on nock travel.
Figure 2. Leading Competitor - Shows the effect of 1/4” stretch on each side of the idler wheel actual distance between lines is nearly 1/2” at the rest position.