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buckhunt
12-10-2012, 08:57 PM
Hey guys

I am shooting a 2012 Shadowcat for indoor spots. I have the nitro 1.5 cams. I thought I saw on here before how to tame the bump on the cam just before it rolls over on my draw cycle. Juat looking for a smoother end to the draw.
Anyone help out? Thanks.

bfisher
12-11-2012, 06:23 AM
I've done this with several of my Rytera bows. It entails manipulating the cam orientation by twisting the string and untwisting the cables. For instance, on my Alien Z I added about 10-15 twists to the string and took out 5 twists on each cable. Now this does make the draw length a bit shorter, but this can be corrected by moving the module to the next longer hole and readjussting the draw stop accordingly. It also changes the bow specs a bit, but I never worry about specs. I set the bow for how I like it and then measure the specs for future reference and let them be what they end up being.

You can try it and see if it suits.

Rootsy
12-11-2012, 06:45 AM
I do it the opposite way by twisting the cables to advance one cam over the other (and wrap up both cams). I leave the string alone. The draw length and max draw weight will both increase. I then back the limbs off for draw weight and use the draw stop to set draw length and let off.

I am currently at 10 and 15 twists respectively (over factory set conditions) on the cables of the Z and I have just about completely lost the "hump" in the draw cycle. My top cam has about double the gap between post and cable as compared to bottom cam. Max draw weight has increased 5 lbs and the draw length about half an inch. Moving the draw stop to set DL @ 27 gives me a 70ish % letoff on my scale.

This is easy enough to play with just keep notes about what changes you made for each iteration of the test so you can put it back the way it was if you desire.

buckhunt
12-11-2012, 08:47 AM
Obviously by doing either you will take the bow out of specs. How does this effect the bows shooting, holding etc...

Rootsy
12-11-2012, 09:34 AM
Obviously by doing either you will take the bow out of specs. How does this effect the bows shooting, holding etc...

In my case, this has brought the Z into spec in some areas. Out of the box it was too long ATA and failed to meet max draw weight rating. BH has always been 1/4" long. As far as performance and shootability... Both have improved. But that is for my bow... Each one will be different.

bfisher
12-11-2012, 12:00 PM
Obviously by doing either you will take the bow out of specs. How does this effect the bows shooting, holding etc...

As I stated above. Whether you go my way or Rootsy's you set thee bow up for the way you want it to feel or perform and let the specs fall where they may. And measure and record each change you make so you can go back to square one if you choose. Specs are just approximations anyway. By using either method mentioned you are customizing the bow to you.

Lab Rat
12-11-2012, 08:00 PM
When you say hump in the draw cycle do you mean how the draw drops into the valley? I think that they mentioned it already but I don't think of the draw length modules as the way to adjust the draw length. I use the drawstop to adjust the draw length to give me the best form position for back tension. So I can pull into the back wall using my back muscles and rotate through the shot. I use the draw length module to set the amount of let off. The higher number on the module the lower amount of let off, if you set the module all the way up then you will not drop into the valley. I like mine setup to pull back smoothly and just ease into the valley. My son likes the Onza setup where it drops off a cliff and the let off feels like you have to push the string forward to release. When I pull that bow back it feels like there is a hump at the end because of all of the letoff -- it feels like I overcame the entire draw cycle in one moment. I can't stand that, but to each his own. It's funny watching bow reviews online when they talk about draw cycles, creep, and back walls. You could set these bows up and hand it off to someone and they would tear it apart for the feel of the draw cycle and you could set it up to make someone absolutely love it in a quick change of the stop and draw modules.

buckhunt
12-12-2012, 08:28 PM
Yes I am looking to get rid of most of the top of the valley feel. Seems to choppy. I do want some let off, just not the hump. If I draw to hard, after hitting the top, the draw cycle falls off hard, slamming the draw stop into the limb. If I draw to soft, I hit the top and the bow pulls me back towards the riser. Hope this makes sense. I will give both a try but it seems like the draw stop and draw module will cause less over all changes...???:confused:

Lab Rat
12-13-2012, 06:16 AM
I think that its a good starting point to adjust the draw stop to your preferred draw length, then adjust the let off or feel of the valley with the draw modules. Higher number for higher let off and deeper valley. Then if that doesn't give you the feel you want -- start twisting. Just remember that once you start twisting the draw length and the draw weight will change so you may have to readjust the stop, modules, and possibly the draw weight at the limb bolts. Good luck.

TEN RING
12-13-2012, 09:29 AM
like lab rat was saying shorten draw lenght with your module then lenghten your draw stop should help before twisting it up, the nitro cam are one of the most shooter friendly cams out there, go shoot a bowtec then come back and shoot your bow you will not even feel the hump

Lab Rat
12-13-2012, 10:20 AM
I agree with Ten Ring before I bought my Alien Z I thought about buying a Mathews Heli. I compared the feel of the draw cycles and the feel of the shot between the Heli and my Onza 3. I could not really feel enough of a difference to justify spending that much more money. Also you can tweak these bows to get them to feel like a pair of old blue jeans without spending a pile on modules.

buckhunt
12-14-2012, 09:17 AM
I was able to get a much better, smoother draw by adjusting the draw stop and module. Less let off and better holding. The only question left is since these are adjusted so that the cam does not turn over as far, is this causing the cams to not be working to the fullest potential? Does this make sense?

TEN RING
12-14-2012, 09:42 AM
I was able to get a much better, smoother draw by adjusting the draw stop and module. Less let off and better holding. The only question left is since these are adjusted so that the cam does not turn over as far, is this causing the cams to not be working to the fullest potential? Does this make sense?

if you want to get the full potential out of that bow at the same draw lenght you would have to go the other way with your adjustment on the module and draw stop then you get you hump back and shorter valley

Lab Rat
12-14-2012, 11:01 AM
I would put some arrows through a chrono. When I sat my bow up this way taking let off away from tha draw cycle sped my bow up. The way my Alien shoots the fastest is with the stop set for my ideal draw length and the module set to give me a very small valley. Remember that the maximum amount of energy stored is making the area under the draw force curve the greatest and taking away the valley will increase the area under the curve. My sons Onza is slower because he likes a lot of let off and has the perception of a bump. The other thing that I did to speed the bow up was to twist the cables which advance the timing but it also increases draw force and increases brace and therefore will make the power stroke shorter. Bottom line if you are out to maximize performance you need to shoot thru a chrono, and tweak. Sounds like fun to me.

Lab Rat
12-14-2012, 11:08 AM
Buck hunt for a good explanation of the draw force curve and kinetic energy check out the hunters friend website. They have an online article how to make a 400 fps bow. When the cams roll over you are actually pulling less weight. You definitely want to climb all the way to the top of the cam but rolling over deep into the valley will give you less draw weight at he end of your draw cycle.

elkslayer4x5
12-15-2012, 08:38 AM
I would put some arrows through a chrono. When I sat my bow up this way taking let off away from tha draw cycle sped my bow up. The way my Alien shoots the fastest is with the stop set for my ideal draw length and the module set to give me a very small valley. Remember that the maximum amount of energy stored is making the area under the draw force curve the greatest and taking away the valley will increase the area under the curve. My sons Onza is slower because he likes a lot of let off and has the perception of a bump. The other thing that I did to speed the bow up was to twist the cables which advance the timing but it also increases draw force and increases brace and therefore will make the power stroke shorter. Bottom line if you are out to maximize performance you need to shoot thru a chrono, and tweak. Sounds like fun to me.

Would'nt a shorter power stroke give you less accereration and therefor less speed? :confused:

bfisher
12-15-2012, 09:45 AM
Would'nt a shorter power stroke give you less accereration and therefor less speed? :confused:

Absolutely. That's why a shorter draw length produces less speed for a given draw weight in a particular bow. It's always been that way and will continue to be so. Never compromise your draw length to get more speed, though. Bow is only capable of so much. You can manipulate cam orientation, add speed balls, shoot lighter arrows and other things to get as much speed as the bow is capable of, but there are limits. What's more you almost have to have a chronograph to check the results of any changes you make.