The Give and Take of Cams
Single cam, dual cam, binary cam, hybrid cam, cam and a half; what’s the story behind all the cam types? Does one shoot better than another? Like so many aspects of archery, it’s good to remember the “give and take” concept when asking this question. For instance, gaining speed makes your bow less forgiving (But that’s a topic for a whole different article.).
First of all, what is a cam? The mechanical definition of a cam is an eccentric or irregularly shaped wheel used in a rotating motion to cause a linear (straight line) motion. On a compound bow, a cam rotates by the force of the bow string.
Let’s look at the different cam types and the give and take of each.
Single or “Solo” Cam
Single cam bows are easy to recognize; they have an idler wheel on top and the elliptical cam on the bottom. The common perception is that a single cam is easier to maintain, since there’s no need to synchronize its rotation with another cam. If that were the case, why wouldn’t everyone use a single cam and skip worrying about their bows being out of sync? Single cam or not, the bow still has timing holes, so, in reality, a single cam bow can be also be “out of tune.”
To further that thought, many archers believe single cams have a short valley and don’t produce good nock travel, meaning there is unequal string pressure against the arrow being shot from an idler wheel at the top and a cam at the other end. At first this sounds logical, but then why do these bows shoot so well in the hands of a skilled archer? The answer is that as long as there is consistency in your bow system and your shooting form, the arrow has a very good chance of making it to the bullseye, regardless of level nock travel.
With regard to the draw cycle, are single cams really smoother than dual cams? It really depends on the bow; some single cam bows are smoother than other single cam bows.
Bows with dual cams will have identical eccentric “wheels” at each end of the limbs. If both cams rotate at the same time (or are synchronized), then you’ll have equal pressure on the bow string, therefore, level nock travel. Will string stretch make your two cam bow go out of sync? Yes, it will. But with the quality of today’s bow strings, you will find the majority of them no longer stretch a bow out of sync. Both cams on a dually should rotate at the same time; I believe it is imperative!
So, what is the extra maintenance that you often hear about owning a two cam bow? It’s not as tedious as you may think. It’s really nothing more than having a qualified bow technician with good calipers and a draw board check the timing and synchronization on your bow at least once every season. There is no real disadvantage to owning a dual cam bow other than having it inspected once in a while (more often if you’re paranoid about it). Obviously, the harnesses should not be unequal in length, causing an imbalance. A knowledgeable bow technician should be able to add or take away some twists in order to balance things out.
The main characteristic that often influences dual cam shooters is that “solid as a rock” draw stop. If you have had the pleasure of shooting a two cam bow with that hard “wall” you may not think as much of the simplicity of a single cam model again.
Less than 10 years ago a new cam system was developed by Bowtech, in which one cam worked as a “control” and the other a “slave.” In this system the cams are connected to each other in a loop, as opposed to the string being physically attached to each cam (like on a dual cam bow) and operating independently.
A binary cam bow is said to provide equalization on bow strings, control cables and limbs via a system that coordinates the rotating of both cams at the same time, because they are “slaved” together. This process has been called “auto-correcting” or “equalizing” everything, giving the shooter a perfect arrow every time. In a binary system, the cams are connected so that one cam physically cannot rotate without the rotating action of the other; the idea is that these bows will never go out of sync.
But let’s go back to the beginning of this article. Remember what I said about “give and take”? A binary cam system may never go out of sync, but because the cams are independent of the bow limbs, thus having no Y-harness or yoke to equalize the pressure on the limb tips, the binary system can potentially develop a “cam lean”. A cam leaning to one side, as we all can deduce, will cause shooting inconsistencies. It’s a subject of popular debate, but common sense tells me that if a lean can develop, it’s definitely something to keep an eye with binary cam bows.
The hybrid cam bow has a power cam on the bottom and a controlling cam on the top connected by a single split harness, cable and bow string. The hybrid system is tuned in a manner which you make adjustments in the draw stop in a coordinated manner with synchromizing the cams in order to get the perfect combination of settings for perfect nock travel. Hybrid cam systems claim to require less maintenance, but they are not the maintenance free solution to all other cam systems as they claim to be, as they still need to be timed properly.
Now that you know all this, I’ll bet you think you’d probably prefer a hybrid cam over the other systems.
Cam and a Half Systems
When Hoyt introduced their cam and 1/2 system, they didn’t fail to point out that one and two cam systems have too much maintenance. Hoyts’ system has a single control cable, one buss cable, and bow string. The cam.5 system must be (or should be) precisely tuned by qualified Hoyt bow technician. Without getting too technical, it’s a little more complex to learn to tune this system, and it will take several attempts, even for a pro, to get everything perfect.
The Choice Has Always Been Yours
Regardless of cam types, each individual bow with its own type of riser, limbs and brace height is going to feel different to each individual. A smoother than average draw cycle may be irrelevant to a shooter who puts speed above all else. Weight and overall axle-to-axle length comes into consideration when it comes to portability in the field while hunting or for forgiveness when target or competition shooting.
If all of the different bow cam systems offer benefits and drawbacks, then what is the best bow for you? The only way you are going to find your “perfect” bow is to go out and shoot a few. Most archery shops will let a serious buyer try the different types they carry. From my experience as a bow technician, my customers have always chosen what feels really good to them and falls in their price range. Then they all deal with their bow’s maintenance idiosyncrasies on a case-by-case basis.
I currently own four bows, and I have also owned and shot each style of cam system. No particular cam type has been a factor in how well I shot. As I said before, the single most important aspect in shooting is consistency, something I’ll explore in depth in an upcoming article.
Also remember: When looking at your world – great optics begin with Vanguard.