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treadwayc
02-06-2010, 01:08 PM
I just purchased an 09 Bengal New in the box and it has 70 pound limbs. However, it is maxed out at 65 lbs. Is there something I can do to get the full 70 lb draw weight? The limb bolts are tight as they will go.

polaris754
02-06-2010, 01:26 PM
what draw mod do u have on it now ?:rolleyes:

treadwayc
02-06-2010, 01:28 PM
F5. 29" draw.

copterdoc
02-06-2010, 01:59 PM
Measure the ACTUAL draw length the bow has right now.

Let us know what it measures.

treadwayc
02-06-2010, 02:03 PM
It is 29 inches. Should I not be able to get the full draw weight regardless of what the draw is set at?

copterdoc
02-06-2010, 02:06 PM
Are you SURE it is 29"?

treadwayc
02-06-2010, 02:14 PM
yes. I am sure.

copterdoc
02-06-2010, 02:17 PM
What does the ATA measure?

Measure from both ends of the axles and average the measurements.

For instance, if the right side measures 32.5", and the left side measures 32", the ATA is actually 32.25".

bfisher
02-06-2010, 02:24 PM
It is 29 inches. Should I not be able to get the full draw weight regardless of what the draw is set at?

Measure the A2A and brace height of the bow to see how they compare to factory specs. If the bow was set up right from the factory then the specs should be pretty close and the draw length should measure correctly for the module used. So, in retrospect your question does have merit. If all these things are as they should be then you are correct in assuming that what module is on the bow has no bearing on peak draw weight. It should be 70# or so with any of the modules.

I suggest a couple of pics showing the cam from the side and one on a slight angle to see where the string leaves the cam to show how the cam orientation is at rest. Also list the limb deflection number.

Any of you Bengal guys have a 70# Bengal? What limbs are on them?

treadwayc
02-06-2010, 02:28 PM
We may have found the problem. It is 32 5/8 it is supposed to be 32 1/4. Now what do I do?

copterdoc
02-06-2010, 02:31 PM
You need to shorten your cable 3/8" and shorten your string 3/4".

After you are done, measure your DL.

treadwayc
02-06-2010, 02:31 PM
The deflection on the limb is 5H. Love the bow. Quiet and shock free, but not getting anywhere near the speed out of it.

bfisher
02-06-2010, 02:35 PM
Yep, limb aren't preloaded enough. It's easier if you have a bow press, but you need to add twists to the cables. How many I don't know because I haven't had these problems. This is where I'll let the other guys help. I'll sit back and learn.

copterdoc
02-06-2010, 02:35 PM
You need to shorten your cable 3/8" and shorten your string 3/4".

After you are done, measure your DL.
Of course, you need to make sure the ATA adjustment was correct as well.

treadwayc
02-06-2010, 02:39 PM
Any suggestions how many twists of string and cable will help me arrive at those measurements. You guys have been huge help. My buddy has a bow press and we are going to press it and see if we can get the specs back in order.

copterdoc
02-06-2010, 02:40 PM
It is absolutely CRITICAL that you measure your DL before and after these adjustments.

If you shorten the the cable more than the string, you will get a longer DL.

It will also make a MAJOR increase in DW. But, it will be a "cheating" increase.

Your bow should get it's advertised DW, at the DL that matches the module.

treadwayc
02-06-2010, 02:44 PM
Thanks I will let you guys know how it goes.

copterdoc
02-06-2010, 02:45 PM
Any suggestions how many twists of string and cable will help me arrive at those measurements...
There is no set number. A string with a lot of twists, gets shorter with added twists, than a string that has less twist in it.

You need to add twice as many twists to the string, as the cable, or you will change the cam timing.

copterdoc
02-06-2010, 04:20 PM
I still think there is something else wrong. I don't think 3/8" of pre-load, will make more than 2# of difference.

DB_43725
02-06-2010, 04:51 PM
I put 5 twists in each of my cables on the warthog and took it from 57 lbs to the 60 lbs it was sepose to be ,, I didnt touch the string,, Anyway this will give you some Idea of where to start,, Its all tryal and error,,as some strings seem to strech more than others, I would say ur best bet is to go to a pro shop so they can make sure cams are timed correctly,, Now with a lot of reserch and reading one can do it them selves as long as you got a bow press. You can also change draw weight adding twists to the string but you also add draw length and that also changes cam timing. Hope this gives you a better feel for what you need to do...

copterdoc
02-06-2010, 04:57 PM
I put 5 twists in each of my cables on the warthog and took it from 57 lbs to the 60 lbs it was sepose to be ,, I didnt touch the string,, ...
You cheated.

In addition to increasing draw weight, you ALSO increased draw length. You could adjust the stop peg, but that will change your let-off%.

copterdoc
02-06-2010, 05:01 PM
.....You can also change draw weight adding twists to the string but you also add draw length and that also changes cam timing. Hope this gives you a better feel for what you need to do...
Adding twists to the string, DECREASES draw weight AND draw length.

Anything you do, that changes the ratio of string-to-cable length, changes the cam timing. Changing the cam timing, ALWAYS changes draw weight AND draw length.

treadwayc
02-06-2010, 06:24 PM
After 3 hours of messing with it, I'm not sure how much progress I made. I was able to do some twisitng and get it to 68 lbs. with my draw length remaining constant at 29 inches. Best I could do on axel to axel was 32 3/8. That is only 1/8 inch off from where it is supposed to be. Still not getting anywhere near the speed I should be getting. I have an email into Martin. Any other suggestions?

copterdoc
02-06-2010, 06:47 PM
You may need to replace the string and cable to get the ATA to where it should be.

If you picked up 3# from a 1/4" reduction in ATA, you should get to 70# by taking it down another 1/8".

I am surprised you got to 68#. I usually get 2#-3# per 1/2".

copterdoc
02-06-2010, 06:49 PM
....Still not getting anywhere near the speed I should be getting....

How much speed ARE you getting?

What is your arrow weight?

treadwayc
02-06-2010, 06:59 PM
If my chrono is correct. I am only getting 255 ft/s with 424 grain arrow. I have bowjax, peep, and D-loop on string. Using OnTarget2, I really thought I would get upper 260's low 270's with the setup. Not even close. My bow doens't have the CCS on it.

copterdoc
02-06-2010, 07:05 PM
How are you measuring draw length?

copterdoc
02-06-2010, 07:08 PM
How close are you standing to the chrono?

What are you using for a light source for the chrono?

treadwayc
02-06-2010, 07:10 PM
very good questions. Light could have been an issure. I was actually in a garage, perhaps not enough light. What is best light source and how close should I stand.

copterdoc
02-06-2010, 07:17 PM
A chrono cannot "see" fluorescent lighting. It needs to be UNIFORM incandescent light.

In other words, you need to diffuse all of the lighting reaching the chrono, so that the "shadow" of the arrow passes over the sensors at the same time as the actual point of the arrow.

It is also important that the arrow pass over the chrono on a plane level with the top of the chrono. It can't pass over the chrono in a "climb" or "descent".

The most important thing, is that the arrow be clear of the string before the point reaches the first sensor.

treadwayc
02-06-2010, 07:21 PM
Thanks for all your help. Althought the string is new, I am going to order a new set and see how that helps. Again, thanks.

RLW
02-08-2010, 06:17 AM
Something I didn't see mentioned was verifying the string is on Pin 1 and not Pin 2.......I know this shortens draw length 1/2", but as I learned on this site and later on a scale, it also lowers max draw weight about 5lbs.

I agree you should be shooting at least 270fps if not closer to 280.
Currently I'm shooting 64lbs (max lbs I get on Pin2), 28.5" DL, 424gr arrow at 268fps

Also agree with the comment on lighting. All my tests are outdoors, shot from 3-5ft behind chronograph.
About the only time I've shot thru indoor chronographs that I thought gave good readings, were ones with optional light kit installed on them

FYI: With correct input, I've found that OnTarget2 program to be very close to actual field results (I use 315 IBO on the 09 Bengal)