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kylecurtis04
05-12-2012, 09:13 PM
Hey guys. Got my new limbs and bow back from the shop and need some help getting it back in tune. I have read the thread over on AT about the CAT cams, but I haven't done a lot of extensive tuning myself so that stuff is like spanish to me. I have a 2011 Silencer and ATA is suppose to be 31.25" and mine is 32" right now. BH is suppose to be 7" and mine is 7.25". The tiller is actually pretty darn close to one another. I will have to get pictures of the cams tomorrow so I can tell if the strings are hitting the groove the same time. but i would like a little more let off. Right now the let off is half way between the - and the + with maybe just a tad closer to the + side. How would I go about getting more let off but still having my cams time up? Also, how do I make twists into the cables with out a bow press?

TEN RING
05-12-2012, 09:49 PM
You can back out your limb bolt evenly look thru the barrel nut just until you can see thru it the limbs will be relax and you can take the strings off to twist them up

Speedykills
05-12-2012, 10:35 PM
FYI: I took my firehawk in to have my cams put back in time,well the proshop timed them and i said it's not in time as both cables were short of hitting in flat part of the modules at full draw,proshop said yes it is in time and the draw stop dictates where the cables hit on the modules.My bow has cat2 cams.
They said that any other bow what i said would be true except martin bows has the adjustable letoff with the draw stop.

wscywabbit
05-13-2012, 11:41 AM
Kyle, first off, now the fun stuff starts; this'll be where you start really learning how these things tick! ;)

Secondly, just an fyi, I checked the past spec chart, and the 2011 Silencer ATA is 32", not 31 1/4. I just set up one and I thought your post sounded a little short. Also, the specs are approximate, so a little one way or the other isn't going to hurt anything.

If you don't have access to a draw board, the easiest way to check timing is to have someone watch the cams while you draw the bow back, to see if they are coming into the flat part of the cam (cable stop) at the same time. You can lower your draw weight to do this comfortably if you want, it won't change the timing. Just back your bolts out the same distance each side.

Also, the draw stop peg DOES NOT change your timing. So you don't need to worry about that. If you want more let off, move your modules one number lower (shorter) and then move your draw stop towards the + to dial your length back in... Just watch to make sure that you are not drawing past the flat cable stops (over-rotating the cams) as that can cause pre-mature cable wear.

Hope that helps! :)

kylecurtis04
05-13-2012, 07:29 PM
Ok guys. I think the cams are pretty well timed up. The pro shop did all this for me when they got the new limbs but just want to get to know how to do this stuff. The first picture is the bottom cam and the second is the top cam. They were take at full draw. Any input would be greatly appreciated.


http://i582.photobucket.com/albums/ss264/kylecurtis04/bottomcam.jpg
http://i582.photobucket.com/albums/ss264/kylecurtis04/topcam.jpg

bfisher
05-13-2012, 08:02 PM
Kyle,

Good pics to work with. Good job. Now let's get into the meat of this.

Looking at the modules the top cam is just a little bit behind the bottom one at reaching full draw. I would suggest using a bow press or using the limb bolts to slacken the rigging and take on turn out of the cable attached to the outer peg on the top cam. Depending on how tight they are twisted up maybe a half turn would suffice, but I'm guessing a full turn.

Next you could move the draw stop closer to the + end. Not much here maybe 1/16". This will give youa touch more letoff. It will also give a little more valley to play with. Note that it's also going to make the draw length just a tad longer so if you're liking the draw as is and like the letoff you can eliminate this step.

From the pics this is what I see. The bow is very close to being right, but just needs a tweak

kylecurtis04
05-16-2012, 06:32 PM
Kyle,

Good pics to work with. Good job. Now let's get into the meat of this.

Looking at the modules the top cam is just a little bit behind the bottom one at reaching full draw. I would suggest using a bow press or using the limb bolts to slacken the rigging and take on turn out of the cable attached to the outer peg on the top cam. Depending on how tight they are twisted up maybe a half turn would suffice, but I'm guessing a full turn.

Next you could move the draw stop closer to the + end. Not much here maybe 1/16". This will give youa touch more letoff. It will also give a little more valley to play with. Note that it's also going to make the draw length just a tad longer so if you're liking the draw as is and like the letoff you can eliminate this step.

From the pics this is what I see. The bow is very close to being right, but just needs a tweak

got the twist taken out of the top cable & its all timed good now. any other suggestions i should check to ensure proper tuning? i thought i read somewhere that a smaller gap between your string a cam peg is better on the nitro cams. is this true?

bfisher
05-16-2012, 08:42 PM
got the twist taken out of the top cable & its all timed good now. any other suggestions i should check to ensure proper tuning? i thought i read somewhere that a smaller gap between your string a cam peg is better on the nitro cams. is this true?

You're referring to a thread on AT---Optimizing Cat Cams or something to that effect. Can't remmber the title. Nitro cams are the same thing so you can look it up. Essentially what you d is twist the cables and wrap the cams up. Of course this mskes the draw length longer so you need to move the module to a shorter setting to compensate. I have never done it, but knowing what I do I wonder just what the net gain really is. I do know it makes the draw cycle harsher and that's not what I'm going to do.

You can look it up and give it a go. When I get my 2012 bow I might play around with it on an older (2011) bow and see what happens.

wscywabbit
05-16-2012, 08:45 PM
I think it was used more as another way to quickly check your cam timing visually, to have both pegs about 1/8" (if I remember correctly) from the limbs...

kylecurtis04
05-16-2012, 10:10 PM
Ahh, thanks guys. I'm shooting the bow great now and it is comfortable. No need to mess around with that right now. Maybe in the summer when I have time to kill. Barry, please post your findings if you toy around with the peg distance. It would be much appreciated.

bfisher
05-17-2012, 06:51 AM
Don't look for it to be any time soon. I still have to get my new bow so I have something to shoot and then play around with the OLD 2011 bow. I'll have to borrow a chrono, too.

Hoestly, my chrono bit the dust a few years back. I knocked over the tripod and it was dust after that. I think it's one of the best things that ever happened to me. For years I chased that mythical 300 fps, but having a 27"- draw length it was a futile attempt. Then in 2004 I got a Martin Slayr, set it up at 27 1/2", tweaked it to the best of my ability and got 308 fps wth an arrow at 5 gr/lb. Then shortened the bow to 27 and got 299 fps. This extra speed added about 4-5 points to my score on a 30 target 3D course as compared to bows shooting about 265 fps.

Since then I've had some muscle loss issues (long story) and look more for a smoother drawing bow without the hump at the top of the draw cycle. I won't shoot a smooth single cam when I can get the same speed with a hard cam, but at 8# less draw weight. To me poundage is just a number. When I get a bow now I set it up and chrono it at the shop to have an idea of it's potential, but never quit tinkering and chaning stuff so really have no idea of the speed any more and it really doesn't matter. If I execute the shot it's there. If not then it does't matter how fast it gets there.