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Discussion Starter #1
Does this look right? Can barely get 50% let-off with this bow. Something isn't right. It's a shoot through system. Thanks! IMG_0588.JPG IMG_0589.JPG
 

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Doesn't look bad. Are those mini-mods? I had a set that were marked 65%.

What you could try is shortening (twisting) the cables some to ****** the cams and move the module one hole shorter to see if that helps with the letoff

Question. How do you know the letoff is only 50%? Did you actually check it with a scale? Reason I ask is that many people who draw these things think there is very little letoff when it is in fact close to what's advertised. It just feels like there's less because the module has a smooth roll over into the valley instead of the precipitous dump like most cams have today. I usually set my orientation about the same as your appear to be and instead of getting 75% mine usually ended up about 71%.
 

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Discussion Starter #3
Barry, I did check it on a digital scale when it felt heavy to me. Was getting just over 50% let-off. I've tried shortening the cables, lengthening them, same with the shoot string. Best I ever got was about 53% let-off. This thing has me baffled. Mods are marked as "T" "HL" on top, and "B" "HL" on bottom. The cams are "C" cams. I've moved the cables enough to shorten and lengthen the ATA by 1/2 inch either way, and still get about the same results. It's set at 35" ATA now. I'd be happy with a 65% let-off. lol
 

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It sounds as if you've done a lot of adjusting. So the mods are marked Top and Bottom, which you already know and the HL is High Letoff which should be close to 75%. Can't say I can help you then. Just on a whim why don't you try Nuts&Bolts?

Wish I knew whether the 2015 mods would fit.
 

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Discussion Starter #5
Well, thanks for trying Barry. Really appreciate all the help you've been over the years. Might give N&B a try and see if he has any advise. This thing has me going in circles. Great shooting bow, just too much holding weight for me. Been trying to figure this all out before I order new threads from Hutch.
 

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Good luck. I had the same issue with the same setup. I never got it worked out. Just ended up selling parts off of the bow. Never had a pair of C cams give me 60% either even when they were the HL 75%.
 

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Discussion Starter #7
Well, that's not encouraging. lol Thanks bc, I appreciate the input. Gonna keep tinkering with it for a while, and see what happens. Wondering if the shorter ATA geometry is the reason. I think all the bows that came out with the Nitrous cams were longer ATA than this 35". Just grasping at straws here....
Might try swapping cams with a Strother I have, and see what happens.
 

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How much preload did you set the bow up for when you ordered strings? The "C" cams work best with around 3.5" total preload from static and you will get closer to your desired result. Did your draw weight max go up more than you anticipated?
 

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Discussion Starter #9
mx, It's a frankenbow I bought. 2010 Warthog riser, 13" 3H limbs, and the Nitrous C cams. Right now at a 35" ATA, it's pulling 50.2#. Holding weight is 24#. I twisted the cables up to shorten the ATA by a good half inch, and that only dropped the holding weight down to 22#. Then I put it back to a 35 ATA since the draw length was getting too long. Knowing virtually nothing about the nitrous cams myself, I figured it was best to ask for advise before doing anything more. It does look like the cams are just a hair shy of full rotation at full draw to me. The limbs appear to have the same amount of flex at rest that my other 2 Warthogs have. I plan on changing it away from the shoot through once I get this let-off problem figured out, and getting new strings then. Thanks for your help!

P.S. Just looked at my 70# hog, and it has 5H limbs, this one has 3H, so shouldn't that be about right for 50#?
 

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Discussion Starter #10
IMG_0590.JPG IMG_0591.JPG These are the cams at full draw. I put 8 twists in the shoot string, and got the holding weight down to 19.98#. Retimed the cams, and this is the result. Still seems way off for a 75% let-off......Also of possible note, the mods are set for the longest draw possible on these C cams, and it's only 28 1/8th inches. My normal draw is 28, so that's workable.
 

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I think MXTuner probably has the best suggestion - you may have too much preload. Another possibility given that you are only getting ~28" max on C cams is that the string and cables are not coordinated correctly. What are the cable and string lengths you are using ? The cam orientation generally looks OK, although I can't tell from the pic if the cables are touching the top cam module at full draw. I am assuming you have center balanced the string and timed the cams to roll over simultaneously.

I can confirm the other comments - I never achieved 75% let off with any Nitrous cams with HL mods. Mine generally come out in the 70 - 72% range. If I recall correctly, my Cougar 3 and Slayer with 14" limbs got closest with 72-73%.

The Nemesis 35 I just converted to Nitrous B cams is giving a touch over 70% (70.25%) let off. I set it up at 35.5" ATA, so a little less pre-load than the stock cams. I could have probably gone to 35.75" to 36" ATA, but it is very shootable like it is. I killed a deer with it week before last ;-)

I may have some old string sets I could send for you to test with. I will check when I get home and shoot you a PM tonight.
 

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Discussion Starter #12
dg, thanks for the help. The shoot string is 44 1/4, and the cables are 36 1/4. The ATA is the same as my other Warthogs @35 inches. Limbs seem to be flexed the same amount, or very close to it. IF I unloaded the limbs a bit, that would drop my draw weight as well wouldn't it? This bow is already down to 49.8#, and I wouldn't want to go any lower really. Plan on using it for a turkey bow if I ever get it figured out. lol
 

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dg, thanks for the help. The shoot string is 44 1/4, and the cables are 36 1/4. The ATA is the same as my other Warthogs @35 inches. Limbs seem to be flexed the same amount, or very close to it. IF I unloaded the limbs a bit, that would drop my draw weight as well wouldn't it? This bow is already down to 49.8#, and I wouldn't want to go any lower really. Plan on using it for a turkey bow if I ever get it figured out. lol
That shooting string number doesn't look right at all. For C cams, the shooting string should be about 19" longer than the cables. Should that read 54.25" or do you really have a 44.25" string on it ? That doesn't really seem possible. With 36.25" cables, your ATA should be about 34.75" (1.5" shorter than cables.) I need to look at my books at home, but I would start with cables around 36.5" to 37" for ATA at 35" or 35.5", and then figure the correct string length from there.

I assume that reducing the preload would reduce the draw weight some, but I am not sure what all is going on with your rig. Those string lengths cannot work with C cams. Again, I will check to see what strings and cables I might have that you could test with to at least see if you can get the let off situation worked out. Then you can figure out if heavier limbs are needed or not, and if it is worth the effort for that.
 

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Discussion Starter #14
Damn fingers. It should be a 55 1/4 shoot string, and 36 1/4 cables. Sorry about that.
 

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Damn fingers. It should be a 55 1/4 shoot string, and 36 1/4 cables. Sorry about that.
OK, that is closer to correct, but the string is still short, which may explain why your available draw length is so short and it may be affecting your weight and letoff. We'll get to the bottom of it...
 

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Discussion Starter #16
Thanks alot dg. Been screwing with this bow for 6 months trying different things. lol
 

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For 35" ATA a person needs 36.5" Cables and 55.5" shooting string. That might be the biggest share of your problem. Before you order strings, take your strings off, leave limbs on. Measure axle to axle with no strings. Subtract 3.5 inches and that is the ideal deflection for that bow. you can go up or down, but you need to have the strings matched. Yours appear to be off.
 

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I've got a set of strings I took off my Cougar 3 Magnum with C cams. That is a 36.5" ATA bow, so the cables are 38" and the string is 57". They may reduce preload too much and yield lower max weight than you want, but at least you could check to see if you get better letoff %. I am still puzzled by the short draw length you are getting. My Nemesis with 35.5" ATA has B cams on the 3.5" setting for 27.5" draw. With C cams I could get 30"+

If you want to try these strings, just shoot me a PM with your address and I'll mail them out. No charge, they're just spares I kept after making new strings for the bow a couple years ago.
 

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I know you guys know what you're talking about and glad that you found this thread to be able to help, BUT, and this is just a thought, but would there be much of a difference with the 13" limbs rather than the usual 14" limb associated with these cams??????
 

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I know you guys know what you're talking about and glad that you found this thread to be able to help, BUT, and this is just a thought, but would there be much of a difference with the 13" limbs rather than the usual 14" limb associated with these cams??????
Not really. The Slay'r started with 14" limbs and then they went to the 13" with the C cams on the Slayer Extreme, presumably to keep the brace lower and maximize the speed. The B cam version of the Slayer Extreme still used the 14" limbs because the cam body width is narrower - 13" limbs with B cams would yield very short brace - under 6". The same general formula for ATA to cable length to string length works on all limbs, from 13" "Super Mag" to 16" straight and the 17" Elite recurve limbs. Some tweaking can improve feel and let off, so the numbers are not set in stone, but the starting point of ATA +1.5" for cables and cables plus 19" for C cams generally works.

I never tinkered with a Warthog, so I am not as familiar with the limb geometry. I am sure the Nemesis 35 has more parallel limbs than the Warthog though, and I have succesfully converted one of those, so I do not think the fact that the Warthog limb orientation may be more parallel than the Slayer would be a problem. I think MBXX may be onto the problem with the starting ATA - the stock cams on the Warthog may have been designed for more or less preload than the Nitrous cams. If the starting ATA without strings is 40", he may be better off to set the bow up as a 36.5" ATA using the subtract 3.5" from unloaded standard MBXX has suggested. What this will do to max weight I do not know, but I suspect it will improve the draw length and let off problems.
 
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