October 28, 2010
By Jon E. Silks
By Jon E. Silks
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Anyone involved with the archery industry for any amount of time knows the LimbSaver name. Sims Vibration Laboratory started a revolution in the archery world during the late 1990s with the introduction of vibration and shock reducing accessories. A set of "LimbSavers" was the sure-fire way to tame just about any rig and usually did so with amazing results.
In 2008 LimbSaver tried their hand at manufacturing a compound bow -- the DeadZone. The response to the new rig was overwhelming for the company, and from that platform they have springboarded into 2009 with a four-bow lineup that includes the new SpeedZone. This speedster is advertised to blast arrows between 348 and 353 fps IBO. It is loaded with features, including the H.E.A.T. Hybrid Cam, reflex limb pocket system, NAVCOM String Decelerator and a host of other noise and vibration reducing accessories.
Hot Cam Design
As the name implies, the SpeedZone is built for speed and draws its power from LimbSaver's High Efficiency Active Transfer (H.E.A.T.) Hybrid Cam system. These eccentrics went through an extensive design process to maximize the amount of energy transferred to the arrow (efficiency) at every draw length. Draw lengths from 25-30 inches are available in half-inch increments through the Hyperdrive Speed Module.
Two basic cams are used to cover the full draw length range. The "small cam" accommodartes the 25-27-inch range, while the "large cam" takes over from there. A draw stop on both the top and bottom cams is used to ensure a solid wall. System letoff is 75 percent. The draw cycle proved exceptionally smooth during testing, and a plotted force draw curve indicated the same.
Sims' NAVCOM String Decelerator incorporates Recoil Pad Break-Away technology, which helps promote level nock travel.
LimbSaver bows feature a unique limb pocket design that grabs your attention. First impressions would tell you this is a radically reflexed bow. However, the relatively large and long reflex limb pockets allow the use of a primarily straight riser and longer limbs while maintaining a reasonable brace height of 5…ž inches.
This system is comprised of a CNC machined aluminum pocket that extends significantly forward of the riser and captures the limb near its end. The last inch of the limb is home to a half-round fixture on its upper face that fits into a receptacle machined on the upper, inside tip of the pocket.
Together with the tension created by the cables and string, this lever locks the limb in place. No limb bolt is necessary. Instead, draw weight is adjusted with a drive bolt located on the forward side of the riser, underneath the pocket. When the drive bolt is turned, it either draws the barrel nut closer or pushes it away, and the pocket naturally follows.
The half-round spacer rotates during this process to create what LimbSaver calls the "rolling-fulcrum." The overall system is designed to utilize two individual working regions of the limb -- one in front of the fulcrum and one behind it. Draw weight can be adjusted from zero pounds all the way up to the maximum provided by the particular limb set. No bow press is required. Limb sets are available in 50-, 60- and 70-pound peak weights.
Mechanical transfer of limb vibration to the shooter's hand is reduced by elastomeric components that completely isolate the fiberglass limb from the machined aluminum pocket.
Two grips are included with the purchase of a SpeedZone. The first is a one-piece, laminated hardwood grip that produces a medium wrist position. The second consists of two NAVCOM side panels, which create a low wrist position. During testing, I preferred the larger wood grip for its comfort and hand placement.
LimbSaver attacks vibration and noise on many fronts. Vibration killers include a set of Solid Limb Ultra Quad LimbSavers, four Cable Leeches, Cable Guard Dampener, integrated Fall-Away Arrow Rest Pad and Arrow Shaft Impact Strip. LimbSaver's NAVCOM String Decelerator, which uses LimbSaver's patented Recoil Pad Break-Away technology with an internal atmospheric air chamber, helps eliminate vibration and promotes level nock travel.
In testing, a notable "jump" was felt in my hand upon release. However, it was short lived and not overly concerning considering the speeds generated by this bow. Shot noise was among the best (lowest) of the speed bows I have tested this year.
Editor's Note: Petersen's Bowhunting standardized testing includes the use of the same equipment and methods on all bows. For more detailed information on testing parameters, go to www.bowhuntingmag.com and look for the "bow testing" link.