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View Full Version : Cheetah...good choice?



cassgen84
10-11-2010, 10:32 PM
I just bought a 2010 Cheetah two days ago. I tested it out at my local store, and I liked the way it felt. Haven't shot any arrows through it since then due to crappy weather. (this is my first bow by the way)

The reason I am posting is that I have been reading all these post about the limbs breaking and the strings getting torn up because of the position of the top idler and the cam. (My cam and idler and not square with the string at rest) So I am just wondering if I made the right choice, or am I just going to be wondering how long this bow will last me before it inevetably breaks???

Any thoughts would help ease my mind. Thanks.

ezbite
10-11-2010, 10:49 PM
Relax, cheetahs a fine bow. I haven't had any problems with mine. Being said that, anything mechanical is subject to failure, Martin will make it right should you have problems. They've always done right by me.

cassgen84
10-11-2010, 11:01 PM
I have read some posts that say when placing an arrow flush with the idler and cam, that the string should be perpendicular with the arrow. Is this true, because mine is not at all.

ezbite
10-12-2010, 01:36 AM
That sounds right to me, but let me check mine when I get home.

bfisher
10-12-2010, 02:46 AM
Not perpendicular, but parallel. Just a matter of correct terminology. Even so, you have the right idea.

J758
10-12-2010, 11:49 AM
Of course! Its a martin! I'd take any martin over a hoyt or a matthews!!! Thatrs right any! I have a bone hunter same thing dicks name. Super silky smooth and shoots very well. In the end its all on. CAN'T GO WRONG WITH A MARTIN!!!!:D

Destroyer
10-12-2010, 03:37 PM
Not perpendicular, but parallel.

Don't setup my bow that way, I think it puts too much twist into the top limb being that the idler is not inline with the cam. All I do is set the idler square to the limb. :)

thomurec
10-13-2010, 08:53 AM
i have had my cheetah for almost 3 years and have never had a problem with it. i love mine.

bfisher
10-13-2010, 04:26 PM
Don't setup my bow that way, I think it puts too much twist into the top limb being that the idler is not inline with the cam. All I do is set the idler square to the limb. :)

OK, so let's talk about this a while. Getting into some detail the limbs are attached to the bow and in line (parallel) with the riser if everything is machined right.

Now you install the idler wheel in the top limb. If all is made right and the axle holes are drilled perpendicular to the limb then the idler has to track parallel with the limb and centered in the limb fork.

Now we install the cam. OK, everything is machined and drilled right. The cam should be aligned (parallel) with the limb, right? Here's the difference. The string groove is offset to the left (RH bow) and not in the center of the limb fork. How much? 3/8"? I never measured one.

NOW, we have a riser, two limbs, and two wheels (cams) that are, for all intent and purposes, parallel with each other except the string groove are offset from each other. Do we agree with this so far?

Now we install our cable and string. Without some kind of help there is no way the string can track perfectly straight with either wheel. The two wheels must be adjusted so they point directly at each other. This can be accomplished with the idler wheel, but there is no such adjustment for the cam.

Now we compound the problem by adding a cble rod and slide which, while pulling the rigging to the side is doing nothing more than twisting the limb tips out of alignment. Adding to this is that the cable rod is not centered in the riser so one limb (Top) is being twisted more than the other. Now our limbs are no longer aligned with the riser nor are the wheels aligned with the riser, or each other.

Now we can twist one side of a yoke to align the idler wheel again. However, we can't do anything with the cam. If it's crooked it's crooked.
What you see is what you got.

So what happens when we draw the bow? Well, without having a way to check let's assume that there is approximately equal pressure on the string and cable with the bow at rest. As we draw the bow peak weight builds and more and more tension is transferred to the cable. At full draw there is maximum force on the cable and minimum on the string. To my way of thinking this has to cause more limb twisting.

Just how much and what effect is has is more than I want to think about. Let's just say that as the cam rolls over these forces are constantly changing. Therefore IMO the amount of limb twist and the resultant cam lean is constantly changing and so is the angle at which they are leaning. No matter how you adjust things it changes as you draw the bow.

So you tell me. Does all this sound right? And just how do we rid ourselves of this malady? I already have an answer, but will wait a while.

FireHawk Owner
10-13-2010, 05:09 PM
Adjust the cable Guard. or make it a shot threw..:D

Spiker
10-14-2010, 04:48 AM
We stop worrying about all that and just tune it so that it shoots the best it can and shoot it???
-- Or X system it. :)

alex
10-14-2010, 05:45 AM
Oneida and Monster bows have eliminated this problem. But their bows are heavy and noisy (or so i've heard) ... and pricey. The other option is to go back to the traditional archery and i admit i'm leaning towards this the last months. But the speed and accuracy of the compounds.... :D
P.S. What about if someday the scientists invent a new material strong enough to allow the use of a kind of double cam not staying inside a fork at the limbs end, but at the two sides of the limb?

Brem
10-14-2010, 06:09 AM
Gents,
Take a look at what G5 has done with its new Prime Centriod and Shift bows. This is what I have been thinking all along.

http://www.g5prime.com/technology.asp

Spiker
10-14-2010, 06:53 AM
Gents,
Take a look at what G5 has done with its new Prime Centriod and Shift bows. This is what I have been thinking all along.

http://www.g5prime.com/technology.asp

Will be very interesting to see where this goes!

alex
10-14-2010, 07:07 AM
Gents,
Take a look at what G5 has done with its new Prime Centriod and Shift bows. This is what I have been thinking all along.

http://www.g5prime.com/technology.asp

I was refering to something similar in my previous post, but put at the left and right side of the limb tips. We will see what the future technologies will offer us.

Destroyer
10-14-2010, 07:20 PM
So you tell me. Does all this sound right?

Pretty much right Barry. :)

My problem is with using a arrow against the idler and having the string parallel. All this does is it aligns the idler with the string, the cam still might be at an angle. Adjusting the lean to get them pointing to each other is even worse since the cams string groove is offset, so you end up putting even more twist into the top limb.

Getting the idler square with the limb is more important, get both square at rest and at full draw square to avoid severe twist, especially with the limbs we have. ;) Now if we had bullet proof limbs we could go nuts.


And just how do we rid ourselves of this malady?

I know that Mathews has designed bows with a offset riser so the idler is inline with the cam.


Will be very interesting to see where this goes!

Yep, if it goes anywhere. Like other tech that comes and goes, this is the one that will change things, just marketing sometimes. Liked the "Cam lean contributes to horizontal nock travel, bow induced torque, and limb fatigue or failure." Shouldn't that be "poor horizontal nock travel"?


What about if someday the scientists invent a new material strong enough to allow the use of a kind of double cam not staying inside a fork at the limbs end, but at the two sides of the limb?

If they invent a limb that doesn't fail then there is no problem at all. And while they are at it, could they invent string material that is not so easy to cut?

ps. The answer might be going back to trad gear, Alex. ;)

alex
10-15-2010, 06:50 AM
ps. The answer might be going back to trad gear, Alex. ;)

I've seen a new longbow backed with carbon instead of fiberglass (190 fps at 50# they say) - if this technology is further developed may be someday we'll have traditional bows shooting at speeds close to the compounds'. The only problem is the price - you'd better buy a car and run over the deer :D

Destroyer
10-15-2010, 05:20 PM
The only problem is the price - you'd better buy a car and run over the deer

Lol! :D

A faster trad bow would be nice but not if it costs that much. I think they're over priced now!