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RobD
01-02-2010, 07:11 PM
09 FireHawk 70# DW trying to preload my limbs to get my Max performance I put two complete twist in each on of my tension strings which come out two 1 1/4 inch for a full twist in string.I can tell that it is performing better, then it was before i messed with it.How much more can I go before i'm defeating the purpose,or jeopardizing my limbs

alex
01-03-2010, 05:24 AM
:( May be i'm wrong, but i think you've alredy done it. The CAT cams are hard for the limbs and if you preload them i guess soon you'll need new ones.

DB_43725
01-03-2010, 06:54 AM
My 09 warthog would only go to 57 lbs and its a 50 to 60 lb bow, so I put 5 twists in the cables which brought it up to 60 lbs on the nose,hope this helps.
DB

RobD
01-03-2010, 09:09 AM
My 09 warthog would only go to 57 lbs and its a 50 to 60 lb bow, so I put 5 twists in the cables which brought it up to 60 lbs on the nose,hope this helps.
DBmine will go to 73# I have it at 70# but I was reading another forum,and seen were they twisted tension string to preload limbs,and they said they probably could get more speed if they weren't worryed that the limbs not handling the load,but {Cracker] never said how many twist he already had,thanks for the input:D

RobD
01-03-2010, 12:35 PM
my tiller is 9 3/8 --- ATA 29 5/8 am i to much if my ATA dropped a 1/8 or is that ok

DB_43725
01-03-2010, 08:24 PM
From what I have read, Its not good to take these bows over Mfg listed max draw weight. Very hard on limbs. But you can back off the limb bolts till is scales 70 lbs. Only reason I done mine was to get it to max draw weight.

copterdoc
01-04-2010, 02:35 PM
You aren't PRE-loading the limbs at all.

You are retarding the cams, which does two things:

(1.) Increases draw weight.
(2.) Increases draw length.

The reason that those factors change is, that you are increasing the total number of degrees the cams rotate during the draw cycle.

That results in more total limb movement, and more string being fed out from the cams. You will get the same results, by installing a longer string.

The only way to increase limb pre-load above what the bow was designed to have, is to shorten the ATA, by installing a string and cable set that are shorter than factory specs. Shortening just the cables, doesn't decrease the ATA much at all.

DB_43725
01-04-2010, 03:22 PM
Good info Coperdoctor,,, I called Martin Tech suport today and ask them if I could put a half inch longer string on my Warthog and he told me if I did I would loose 30 to 40 ft per sec in arrow speed. :eek: So rather than experment I put that on hold. Still my try it some day seeing is beliveing,,lol

copterdoc
01-04-2010, 03:43 PM
I see a lot of threads claiming that somebody changed their cam "positioning" and picked up some speed, or that they finished "tuning" their bow and it was so much faster that they had to move their sight pins closer together.

Generally, I consider those claims to be the same thing as saying that they painted their car red and picked up 5 MPG better mileage.

The fact is, that cams are only cams. They can't become more efficient, without physically being changed.

If somebody played around with their cam timing and picked up some speed, it was because they either increased the length of the power stroke, or they increased the draw weight.

A bow equipped with cams that are going to be set at the minimum draw length setting, is usually going to be less efficient than one that is set at it's maximum draw length setting. That is simply because smaller cams have less mass for the limbs to move and they usually have a shorter brace height at the same draw length, which means they will have a longer power stroke at the same DL as the bigger cams will.

FireHawk Owner
01-04-2010, 08:18 PM
09 FireHawk 70# DW trying to preload my limbs to get my Max performance I put two complete twist in each on of my tension strings which come out two 1 1/4 inch for a full twist in string.I can tell that it is performing better, then it was before i messed with it.How much more can I go before i'm defeating the purpose,or jeopardizing my limbsI have the same Bow 29 inch draw length 70 lb draw ,I tried everything when I first got this bow to get more speed,thought that I would get at least what they post on there sale pitch 315-320+,well thats bull,when i got the bow it was shooting 287 FPS out of the box,I called Martin ,figuring they sent me wrong draw weight,then i brought it to a Martin dealer to get it tuned,290 FPS they got it shooting,and showed were my servings were wearing, I was very upset it wasn't even getting 300,and my serving were wearing quick ,I started twisting strings ,and adjusting the cams tring to find the sweet spot they call it,well,Crack ,my limb broke,call martin they replaced under warranty,well to end this im getting little over 300 FPS now,but i gave up tiring to speed it up .I went a got a Mathews Monster for my speed bow,this thing SMOKIN 339 FPS OUT the box,everything they say it is +,but I still have my firehawk,and its a good bow,Have to say I learned a lot from having the FireHawk,So just be careful with over loading them limbs,Hope It works out for ya.

RobD
01-05-2010, 06:55 AM
I have the same Bow 29 inch draw length 70 lb draw ,I tried everything when I first got this bow to get more speed,thought that I would get at least what they post on there sale pitch 315-320+,well thats bull,when i got the bow it was shooting 287 FPS out of the box,I called Martin ,figuring they sent me wrong draw weight,then i brought it to a Martin dealer to get it tuned,290 FPS they got it shooting,and showed were my servings were wearing, I was very upset it wasn't even getting 300,and my serving were wearing quick ,I started twisting strings ,and adjusting the cams tring to find the sweet spot they call it,well,Crack ,my limb broke,call martin they replaced under warranty,well to end this im getting little over 300 FPS now,but i gave up tiring to speed it up .I went a got a Mathews Monster for my speed bow,this thing SMOKIN 339 FPS OUT the box,everything they say it is +,but I still have my firehawk,and its a good bow,Have to say I learned a lot from having the FireHawk,So just be careful with over loading them limbs,Hope It works out for ya.Seems like you have been were I am.LOL well I don't want to break a limb,and seems im going in the wrong direction ,from all the replys on my question,And yes thats what i was trying to do is get a little more speed out of it,I had a Matthews DTX before I bought this bow,it was way faster, ,and should have got this bow before I sold that one.But ,I'll be fine with It.Thanks for the reply