# Changing the poundage on my bow



## dahmer (Jan 16, 2005)

To add more poundage why didn't you turn in the limb bolts instead of twisting the string?


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## shaun748 (Aug 11, 2004)

I bet he was just trying to change the ATA length to get back in specs(was it a Mathews?)..I speak as a mathews owner, but If I had a dime for everytime I hear Mathews say "SPECS" I would be rich!! If you own a mathews you live in this world of 1/8 inch increments..I finaly gave up and just tuned mine where it was at since these 1/8 variances in specs drove me nuts.

ANYWAY,yes, your nocking point moved and if you added poundage(ie, ATA is now closer) your draw length also increased a small amount,unless you made corresponding string adjustments to compensate. 

you can also move your nock point by turning the limb bolt,,,as an example,your nock point is high, tighten your bottom limb bolt about an 1/8 turn and it will pull it back down.,, ,,

any time you add/take out twist in any sting/cable the nock moves(generally not a lot if only 1-2 twist, but it does move).

depending on how much LBS you added you might verify tune since arrow spine might be affected also, again will depend on how much you added.


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## Southern Hunter (Apr 18, 2005)

*Poundage*

It was not a Mathews bow it's a bowtech extreme solo cam. I turned the limbs all the way down before and the only thing I noticed was it seemed my tiller changed more downward at full draw. I thought the only thing that changed the poundage was changing the turns in the cables and turning your limb bolts would change your tiller?


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## shaun748 (Aug 11, 2004)

"tiller" is just the distance from the limb to the string(it is checked while bow is at rest). it will change anytime you change the agle of the limbs...adding twist to your cable will INCREASE tiller distance and loosening your limb bolts will do the same..

un-twist cable and limbs move foward DECREASING tiller,,tighten limb bolts does the same.

it sounds confusing,but one day, if you really study the design of compound bows & start working on them, it will just click and you will understand the cause/effect of each change you make.


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## Southern Hunter (Apr 18, 2005)

*tiller*

Ok I am confused, if I twisted my strings to increase the draw poundage I would be lenghten my draw by changing my ATA and add more downward force to my bow. Should I loosen my bottom limb or would I be adding more downward force to my bow at full draw? Or at this stage should I tighten my bottom limb back to it's original setting and loosen my top limb to decrease the downward force I am feeling? Since I had this done I have changed my stabilzer and went smaller (less weight). The bow just feels different sort of bottom heavy and not balanced at full draw.
My bow
Botech extreme 70# set to 65 # draw/peak
29" draw
65% let off was at 75% more or less


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## shaun748 (Aug 11, 2004)

it is hard to explain by typing, but at some point it will just 'click" in your head and make sense. you are getting the idea, just think about what each part is doing then play around with it..it took me "YEARS" before it just clicked one day and I have been working on mine ever since. 

now in regards to bow balance I am not that sure what to tell you, sounds like your top limb may need to tighten the limb bolt to make it go back foward to put more weight foward over your hand(you would have to experiment there)..it might just b imagined also

picture that your bow limbs are under pressure and want to spring foward all the time. if you took your string/cable off your bow would be "almost straight" and the limbs would have no pressure. when you put string/cable on the bow limbs bend and are under pressure.

when you twist your cable to shorten ATA you also make the DL a little longer. you also get into cam over-rotation..shorten your ATA and your cam will began to over-rotate foward.

the more pressure the limbs are under, the more poundage..so when you twist the cable it "loads" the limbs more(as an extreme exageration you might say you bend them closer to breaking point as your ATA distance decreases). well that shorter distance between axles means that that string length will get longer allowing the cam to over-rotate foward, hence the reason you have to twist both to keep your cam setting the same.

when you un-twist the cable the limbs relaxe and the cam wants to rotate back toward you since the string is now "shorter".


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## Southern Hunter (Apr 18, 2005)

*Thanks for the help*

Thanks Shaun748 I think I understand, I will work on it tomorrow. I belive what you have explained to me makes sense. I must try to understand the opposite forces at work. I will let you know how it comes out.


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## shaun748 (Aug 11, 2004)

good to hear you are trying to figure it out,,sounds like you are getting it...trust me, you are no differant than most of us..years ago all this tuning cause/effect sounded like "black magic" to me also..
you could not pay me too touch my bow..this was back when I had 2 wheeled bows with steel cables, you think single cams are confusing, try synching a 2 cam bow.

then one day I just sat & looked at my bow and thought about what each string does and "what does what" when I draw back, suddnley it just all began to make sense..

it sounds stupid, but draw your bow back and watch the parts move, then just stand you bow up against the wall and stare at it as you imagine what each part does and I bet it will just "click" from that point on.

I will never be a bow tech and don't know all the tricks, but I know enough to tune my own bows...believe me you will be glad you learned,many people pay a shop $30 just to put a string/cable on their bow, you will know how to put it on & tune it yourself. 


good luck..


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## Archer 1 (Feb 10, 2005)

One thing you have to remember is on a solo cam bow any twists to cables or string will change your nocking point,you will have to reset it whenever you twist or untwist.


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## Arrroman (May 11, 2003)

Southern Hunter said:


> Ok I am confused, if I twisted my strings to increase the draw poundage I would be lenghten my draw by changing my ATA and add more downward force to my bow. Should I loosen my bottom limb or would I be adding more downward force to my bow at full draw? Or at this stage should I tighten my bottom limb back to it's original setting and loosen my top limb to decrease the downward force I am feeling? Since I had this done I have changed my stabilzer and went smaller (less weight). The bow just feels different sort of bottom heavy and not balanced at full draw.
> My bow
> Botech extreme 70# set to 65 # draw/peak
> 29" draw
> 65% let off was at 75% more or less



The bow should be adjusted back to Bowtech specifications for best results.

Bowtech has a download that decribes the tuning gap for the cam, the correct ATA length and the correct braceheight for your bow.

I would reccomend setting the limbs at max, then setting the correct ATA and tuning gap for your cam. At that point you can nock an arrow at 90degrees to the bowstring and you will be good to go.

Twisting strings and cables is a balancing act. Because the bowstring and the cable are different lengths one will take twice as many twists as the other. 

When I changed the strings on my VFT Extreme I had to press the bow seven times before the ATA, brace height, and tuning gap all matched Bowtech specifications.

The tuning gap is the minimum distance between the inside of the lower bow limb and the edge of the allen screw closest to where the bowstring wraps around the cam. Bowtech gives a measurement of about .410-.450" on my bow. That translates to about 7/16" for me.

Your bow's ATA is probably on the bow somewhere. I'd check that first.

Good luck tuning your bow!

Good luck hunting! >>>------------>


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