Could someone explain the Cam & half?
 

I notice some of the new bows have Came & Half. The bow mfg. say there are "no timing issues" How can this be?
(You can tell I don't know much about bows)

RE: Could someone explain the Cam & half?
 

There are still two cams and they still have to be timed, however the range of acceptable timing is larger (in theory). My own (limited) experience is that you still have to pay critical attention to timing if you want your bow to shoot it's very best groups. In fact, with my initial hybrid cam bow, I had to spend quite a bit of time messing with the timing before I could get it to shoot a bullet hole in paper. I then monkeyed with it even further to get my best vertical grouping while group tuning. I found it a real pain in the rear-end to continually have to press the bow, put a 1/2 twist in one cable, remove one from the other cable, and so on. Shoots real nice once timed and tuned, but don't think for a second that they require "no timing"

RE: Could someone explain the Cam & half?
 

Hoyt claims there are no timing issues with the camand half. I have the hoyt xtec and love it but I have to disagree. I just recently took mine to fix the poundage(a previous post) and my pro shop checked the timing of the cams. I asked about this, wondering the same thing as you. He told me about a guy that shoots semi pro for hoyt, this guy said the hoyt cam and half shoots best with the top cam out just slightly, meaning that at full draw the bottom cam hits the wall first. The boy who figured this out used the hooter shooter to come up with this opinion. I do not no to many details at this time, just that when it was in time it shot 5 inches low and with the top cam slightly out it hit dead on. I am not sure if this answered your question, but I hope it gave you some insight on the cam and half. I am sure some others will respond to your post. They may agree or dis agree.

RE: Could someone explain the Cam & half?
 

Thanks for the info!:) Yep, thats kinda, what I was afraid of, but didn't really know enough about what a "Cam & half" really was.

Thanks again, I now know, that I don't want one, I wouldn't know how to time it IF I had the equipment.

Thanks Straightarrow & ash2042 again!!

RE: Could someone explain the Cam & half?
 

Absolutely the cam and a half and other hybrids have to be timed. And the cam and half is also somewhat susceptible to "synch" problems (though not to a large degree)

Basically there are two types of hybrids. Hoyt's system (which browning also uses) which is a little closer to a two-cam bow (it uses a cam shaped track at the top for take-up), and there is the CPS (Controlled Power system) that uses a round take up track (like the idler of a single-cam) which Darton, Martin, Merlin,Champion and some others use.

They are both very similar, however due to the difference in the top "cam", the Cam and a half is susceptible to out-of synch conditions (like a two-cam bow, but not nearly to the same degree). The Cam and a half also does not generally yield perfectly straight and level nock travel through the entire draw length range of each module size (generally performing best at the short and mid length settings), however the nock travel is still better than many single-cam bows.

The CPS has better nock travel throughout the entire range of draw lengths. In fact it's pretty much dead level and straight unless you really goof them up or set up them up incorrectly (assuming it's on an appropriately built riser design that allows for perfectly level nock travel..not all CPS bows are).

I shot the CPS on several bows for several years (including a current 2004 model) and have also owned 4 bows with the Cam and a half. I think in general the CPS style draws a little nicer: it peaks sooner, rolls over smoother and lets off sooner. The Cam and a half is a little more bumpy (but certainly not objectionable) rolling over. I do like the cam and half better overall though because as Ash pointed out it's a little easier to tweak to get a more forgiving set-up (somewhat like a dual cam that can be set slightly off synch to cause the arrow to lift slightly off the rest during the power stroke). You can do this with the CPS too, but like SA spoke of, they can be more finicky when everything is not in perfect harmony. The Cam and a half seems to relish the *slightly* "out of harmony" settings. However the Cam and half can get dowright horrible accuracy-wise if the top cam is over rotated. Most of the Cam and half bows coming into the shop are set-up quite well out of the box, but on occasion I've seen some that were not set-up correctly.

So in essence they both can get out of time, and the Cam and half can also get out of synch so to speak , however neither are nearly as critical as two cam bow (or some one-cam bows) under most circumstances.

With a high quality string and cables, both are easy to set up by a competent tech, will stay that way, and offer very good or perfect static nock travel. I would be more concerned with purchasing the model that fits and feels best (and making sure you have that high quality rigging) than worrying about whether it's a CPS or a Cam and a half. They are both extremely accurate, shootable systems.

RE: Could someone explain the Cam & half?
 

Jeff, I'm guessing that this has something to do with where the company decides to put their bow's riser cutout. The "arrow center", must vary from one company to the next. Do you know, if true center of the bow is what they need for the best nock travel with these cams?

RE: Could someone explain the Cam & half?
 

Exactly. A "below center" grip will help to alleviate nock travel issues, unlike the older days when on most designs the grip's throat was at true center.

Also note that bow must be drawn from that center position. Meaning you need to use a loop directly behind the arrow nock (or something like a "gatorJaws" release).

Some Pro shooters who shoot singlecams with less than optimal nock travel will nock under or tie a loop under the arrow nock as they believe it helps offset the nock travel issue. I've tried it. On some bows I felt there was a slight improvement. But it could have just been my subconcious at work :)

Another factor that is often ignored (or perhaps many are not aware of) is the limbs. Limbs must be of excellent consistency to get consistently good nock travel from bow to bow to bow in a production run.

RE: Could someone explain the Cam & half?
 

So, if I adjust limbs to uneven tiller, in an effort to change grip pressure, I will now have a different nocking point that will not be in the center of the bow. Is nock travel now negatively affected?

RE: Could someone explain the Cam & half?
 

Jeff brought up many good points on this one that cannot be overlooked--

1) That there are two different types of "hybrid" out there-- Hoyt's is more like a true twin cam with respect to their eliptical cable track which, depending upon drawlength, may or may not offer level nock travel because of it. Twins have straight travel, but not level, so the cam.5 is a step forward if you hit the correct drawlength.

2) The CPS/Merlin Omega type systems have a perfectly round cable track and can offer very. very straight and level nock travel at all drawlengths---this allows shooters to use a wider variety of arrow selections, and allows for easier tuning across the board. Remember that ALL bows require tuning---twins, solos, hybrids, all of them. Solocams for instance are very finicky of arrow spine and normally do NOT allow straight and level nock travel at all drawlengths, and especially those that offer drawlength adjustments over a wide range on the cam. I have found the hybrids to be the best of the cam selections simply because the CPS/Omega type allow for "set it and forget it" tuning and some brands even come with complete instructions on how to do this for best performance. They offer the best attributes of BOTH twins and solos, and take most fallicies of the two out of the equation. They're not susceptable to nock point movement like solos are because both ends are slaved, and they are not as finicky as a pure twin so you need to get it down to the nearest 1/2 twist to find the "sweet-spot" for great flight and groups.

3)Another great point was limbtip travel and it's association to different cam designs---all bows should have both limbs firing at the same time and a geometry capable of allowing this for best performance and consistency. Solocams are notorious for NOT allowing this due to different sized and radiused cams and idlers---throw your favorite bow in a crankboard, run it out to full draw, pencil around the limbs, back it down halfway, pencil again, and measure between the marks---are they the same? If not, you may be experiencing poor accuracy due to the "kick" of one limb firing completely before the other...not good as a rule. Some shooters alter their bows' geometeries to help with holding and allow the limbs to fire one before another---this IMHO is also detrimental to proper accuracy and performance, and one should find a bow that holds good and fires with even limbtip travel for best consistency and forgiveness.

Many many manufacturers now have a version of the hybrid, and it is without question the next step forward in the evolution of compound cam design. All who do not offer one soon will,(well, except maybe Mathews;)) and we will soon see new and improved variations of this design in the coming months and years, simply because there is much room to move forward technically with this system as opposed to others. Good shooting, Pinwheel 12

RE: Could someone explain the Cam & half?
 

Possibly. Depends on how “on” the bow was in the first place. You could make it worse, you could make it better.

However my comment was geared more towards a term called “flex modulus”. Which I am only familiar with in a general sense, but itwas explained to me by some industry-folk/engineers. But it basically comes down to the fact that ALL limbs have some inconsistencies and imperfections due to their makeup. They flex at very slightly different rates even on bows with what many would consider “perfectly” matched limbs. In essence: to get every single bow in a production run exactly the same as regards to nock travel, you would basically need to swap limbs matching it with different cams/cam, make sure string and cable lengths are absolutely perfect, and then test each individual bow for nock travel to see it was correct. If it wasn’t perfect, then you’d need to swap out another pair of limbs, or perhaps there’s a very small (normal) deviation somewhere else in the bows makeup (cams,idlers, normal machining tolerances, etc) that’s causing the problem. The better the tolerances, the less variation you will have.

So chances are that even if one bow X has perfect level nock travel, the next bow X may not. If the company is known for super tight tolerances, then most likely it will be very,very close from bow to bow to bow..as perfect as can reasonably be (and IMO, nock travel is somewhat overrated), but only when extreme attention is applied to each and every bow will you get perfect results from each and every bow. This unfeasible for most manufacturers since they cannot reasonably devote so much time to each and every bow when producing them by the tens of thousands. So you likely will get a few perfect ones in a run of bows, a bunch of good ones, and some that are “acceptable” (or not, depending on the individuals own regard for the importance of nock travel).

This is why in the past few years I’ve become more tolerant of less than optimum nock travel. It’s a good thing to have for sure, but I suspect that most folks (including myself) are not getting it right out of the box even with bows that are supposed to have it. It’s going to require a little or a lot of tweaking, and since most people don’t have access to the proper equipment (either a tuning machine if you are believer of the static test, or a high speed camera if you feel dynamic nock travel is more important), then for most folks it’s just “peace of mind”. There are tangible benefits, but do you know if you are getting them, or do you just assume so? In your case SA, you might have actually made the nock travel worse or better, but what you did was fine tune it to where it shoots best for you as an individual. Which in essence is the real key AFAIC.

Sorry to go off on a tangent and hijack the thread..it was not my purpose.