Len in Maryland

First, let me explain a few things - now that I have your attention.

I got home from the shop at 8 PM EST. Grabbed a plate that my wife has learned to put aside for me and nuked it. She learned a long time ago that 'dinner hour' when you run your own business doesn't mean a thing.

I couldn't get into it this morning because I have to run a business. I did my testing before the shop opened. Keep in mind that the information that shop owners give to this and other forums is mostly through promoting the business in general across the country. Most of us don't get much or any business from the Internet/forums. This is also a reason why you won't find many Dealers, including myself, handing out personal information as many non-Dealers are willing to do. There is nothing wrong with helping each other. It's just that my customers have to pay for it, and giving it away for free takes time away from them and can be a disservice to them.

You might have noticed that I recently started a 'signature' on my posts. I never did this before until I got harshly criticized by a new member of the forum about a week ago. I took some offense at first, but then realized that he really was being questioned by an unknown to him - ME. I just felt that it would be better to show some of my credentials for those newbies.

The subject at hand, however, is one that is not 'personal'. It has a direct affect on a new cam design and the industry as a whole. It's going to take me about an hour to prepare a detailed response. So, please bear with me.

I will preface my report as it being somewhat of a matter of semantics and misinterpretation.

JOE PA

OK, I can take an uneducated guess like some others.[8D]

How about the limbs are ground on a slight bias so the right (cable guard) side of the limbs is just a bit stiffer than the left side of the limbs. If so it would appear the the top cam (which should be the one most people look at) seems to be leaning to the left a bit at the top at brace height. As the limbs flex, the right side flexes less, and the limb remains straighter than it would if the cable guard side loaded the limb harder on the right side, keeping the limb and cam straighter at full draw.

J in GB

Glad you are feeling better bud. You looked like death warmed over yesterday! Good seeing you as always though.

I am anxiously awaiting your conclusion.

JB-

Len in Maryland

I think it's great that some took the initiative; and, some of you were really on the right track.

When I first made comments about this new cam system, I said that it would take some time to really evaluate its positives and negatives. I still hold to that statement and will continue to analyze this product. A few have made a real issue about 'cam lean' that grew into a furor and quite a controversy in recent weeks. As with many issues on the forums, it was getting emotional and needed some context.

I had done some evaluation of its shooting characteristics/consistency and was impressed. I took one bow apart and did a tolerance check and was again impressed; especially with the axle fit to the limb and bearings. If anyone has the capability, I'd like to hear their input on these matters. After all, I've only been able to take a small sampling of the dozen units I have in stock. I plan to sample more later; but, I like to take samples from different 'lots'.

One thing we have to do is DEFINE cam lean as it is different from limb twist. Just like the definition of timing and synchronization can be confused, so can these terms. We also have to understand when things can be controlled, IF they must be controlled, and HOW they should be controlled. It is best to distinguish between these two for various reasons. First, identifying the causes becomes easier if you're analyzing both. Second, and in this case, it's more fair to the cam design. I'll explain later. *

Cam lean may be what you're seeing because the cam IS leaning; but, what is the cause. I refer to cam lean as a variance in the degree of straightness due to worn bushings and/or bent axles. Limb twist is where the limbs 'bend' due to various influences. In this case the influence would be the cable guard. There are other cases of limb twist which are permanent. This was the case in some older designs and some of the split limb designs that were manufactured inexpensively. In this case and in every case of bows using a cable guard, limb twist WILL be an issue.

During my Dealer Seminar at the ATA Show, I discussed the usage of lasers and how just one method shouldn't be totally trusted. This is apparent moreso now that this issue arose. If you laser or even straight-edge the cams, they will show minuscule lean in the static mode. In the dynamic mode, however, the lean becomes more noticeable. If I use one laser design, it just shows me cam lean. I have to use a second design that will tell me if the limb is twisting. If the two agree, it reads one way. If they do not agree, it reads another way.

I checked my entire stock of BowTech Binary and many other manufacturers, which is substantial. The amount of cam lean in the static condition was better than most. The dynamic condition for the binary system was average to better than average. Even the much more expensive limb designs were not significantly better.

Keep in mind that Gordon Glass builds about 80% of the limbs in the market. What we're really seeing, in not only in the design but the construction, is 'commonplace' with today's technology. And, it doesn't matter whether or not you have a split yoke system, there will still be limb torque/twist when using a cable guard. By adjusting a yoke, you're really just preloading the limb. It then becomes critical as to how much you're 'influencing' the end result. I've seen situations where the cam lean/limb twist was corrected by twisting yokes to the point where the cable(s) MISSED the stop(s). I've done a lot of dual cam bows for some tournament shooters. It's a tenuous job of obtaining that 'balance' of the system for optimal results. Can you get a better shooting bow? Yes, but it would take a top-notch shooter to see the difference. In most cases it would be a "feel good" situation.

What I have found is that the cam lean/limb twist in this design is really not as much as we've been subjected to for a decade - and we shot those well. I also have noticed nowhere near the cable wear as has been experienced with other designs. This might change, but I have my doubts.

*The reason I decided to report my findings at this time was not that cam lean wasn't there; but, that it was being misinterpreted and somewhat blown out of proportion. I must admit that I was negligent in doing the dynamic tests right away. The bows were shooting so well that we didn't see an immediate need. We have tuned these bows easily and shot FTs and FIXED BHs into the same holes at around 300 fps @ 25 yds. We haven't had the opportunity to do long-range tests because of the weather/facilities. If someone else could chime in on their long-range FIXED BH results, I would love to hear about it.

Well, that's all for now. Thank you for your patience.

Dairy King

Ok, Im confused. Do they lean or not? If not, whats making it look like they are?

Kanga

Len I have shot groups @ 40 & 50 yds with my Allegiance and at both distances my muzzy 3 blade 100's group with field points when I do my part.

BOWFANATIC

Yes!! But you should be as worried about it as you should be about miniature anal dwelling primates flying from your arse!

gibblet

i hate those monkeys

PABowhntr

Thank you Len for taking the time to run extensive tests on the system. I haven't happened over to the Bowsite yet today. Is it possible you posted your results there as well?

silentassassin

Great report Len! Thanks for taking the time to not only do the testing but also to come back and report it so thoroughly!