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hunt123
08-13-2010, 02:59 PM
What is the optimum cam location on a '10 Bengal? I twisted up my cable and got the ATA set exactly to factory spec 32 1/4". At that spec, there is about 1/4" of open groove on the ball end of the cam between the end of the groove and where the string hits the cam.

Is that optimum or is there a different distance like maybe 3/8" that's better? Where the cam turns over is maybe more important than having an exact ATA and I'd like to get it correct. I can't find any Martin data on it.

Sagittarius
08-13-2010, 04:00 PM
My 09 has 32 1/4 ATA The distance squared from the string to the upper end of the exposed part of the groove is 5/16 of an inch.. If that helps ???

hunt123
08-13-2010, 05:51 PM
My 09 has 32 1/4 ATA The distance squared from the string to the upper end of the exposed part of the groove is 5/16 of an inch.. If that helps ???
Pretty close to mine. Just 1/16 more. I guess that's probably what you get if you set up a factory spec ATA. But what I want to know is: is that really optimum or would it be better in some way to make it a little more or a little less.

bfisher
08-13-2010, 05:56 PM
Pretty close to mine. Just 1/16 more. I guess that's probably what you get if you set up a factory spec ATA. But what I want to know is: is that really optimum or would it be better in some way to make it a little more or a little less.

The best way to answer your question is for you to play around with cam position and find out. #1 you should have a chronograph to check speed differences. #2 you have to shoot gor groups to see if there is a sweet spot that suits you and your bow. There just aren't many hard and fast rules about it.

hunt123
08-13-2010, 06:07 PM
The best way to answer your question is for you to play around with cam position and find out. #1 you should have a chronograph to check speed differences. #2 you have to shoot gor groups to see if there is a sweet spot that suits you and your bow. There just aren't many hard and fast rules about it.

Wish I had a chrono or even access to one. Guess I'll have to do it the laborious way. :)

Destroyer
08-13-2010, 10:02 PM
here just aren't many hard and fast rules about it.

Exactly right. My bow tunes easier with less rotation but is a bit slower. There have been quite a few threads here about the very subject. :)

hunt123
08-14-2010, 05:25 AM
So lets see if I'm understanding everything right. Factory spec is only a starting point and you work from there.

If your string and cable are the correct length and are good quality so they don't keep changing length, then you just adjust your cable one way or the other until the bow shoots good. Forget what the factory ATA is.

No need to mess with the string unless your peep starts twisting.

Stuff like centershot, loop height, peep location, etc. isn't under discussion right now. Just assume all that is correct.

Right? I'm never going to get to "Crackers" level, but I'd like to get better than I am! :D

elkslayer4x5
08-14-2010, 07:14 AM
So lets see if I'm understanding everything right. Factory spec is only a starting point and you work from there.

If your string and cable are the correct length and are good quality so they don't keep changing length, then you just adjust your cable one way or the other until the bow shoots good. Forget what the factory ATA is.

No need to mess with the string unless your peep starts twisting.

Stuff like centershot, loop height, peep location, etc. isn't under discussion right now. Just assume all that is correct.

Right? I'm never going to get to "Crackers" level, but I'd like to get better than I am! :D
You're going the correct way, ask questions, try things out, if in doubt, ask more questions. You 'mess' with both string and cables. Have you read Ehunter's post "New string/cables ? See post #3. :D
http://www.martinarchery.com/mtechforum/showthread.php?t=7423

polaris754
08-14-2010, 12:41 PM
sounds like hes gonna crack a limb to me lol:D

hunt123
08-14-2010, 02:42 PM
sounds like hes gonna crack a limb to me lol:D
I'm not amused. Martin's already replaced at least 3 sets, none of which were my fault. All had to be replaced before I started messing with tuning.

polaris754
08-15-2010, 05:10 AM
oops sorry hunt 123 it just seems to me every time i see some folks trying to get the max out of there bows , it was shootin great , then crack sorry again dude:)

bowgramp59
08-20-2010, 05:03 PM
i have 3 moabs one has a m-pro cam the other two have m-2 cams . there is a big difference in the 2 . on my m-pro cam there is 3/4" from where the string hits the groove to the end of the groove, and the m-2 cams it's more like 1 1/8" from where the string hits the groove to the end of the groove. all my bows have the proper measurments , brace ht, ATA, 60# peak wt. the best way to achieve the proper measurments is take your string and cable off the bow and put them on a string jig that can put tention on the the string, the length of the string and cable should be checked and set under 90#s of tention, twist or untwist until your string and cable are at factory specks,i know everone doesn't have axcess to a string jig.i measure my strings from the inside of the loop on one end to the outside of the loop on the other end. i think that the least amount of twist you have in your string the less trouble you will have with you peep. but you have to put enough twist to keep the string round, don't want a flat string. it works for me. sorry for such of a long reply. good luck