# Finally got rid of left tear and now have bullet holes



## Ray.Klefstad (Oct 7, 2006)

I have some good news to share.

I had two different mathews bows (my older conquest and my buddies new switchback) and both had a tear left (nock left) that I just couldn't get rid of by adjusting the rest. They would show a left tear with both bare shaft and with fletched arrows. My buddies bow was new from the mathews dealer and he couldn not get broadheads to group with field points no matter what he tried. Even the mathews dealer wouldn't fix it.

I read through many posts here on the subject, then I adjusted the cam lean on both bows and shot after each adjustment. Now both shoot perfect bullet holes with both bare shafts and with fletched arrows. It did take several hours per bow, so I can understand why the dealer may not have wanted to spend the time to fix it.

Thanks to all who suggested adjusting cam lean for nagging left tear. I just couldn't stand to shoot the bow like that as it tended to cause fish tailing. Now they shoot like darts (like they are supposed to).

Ray


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## nccrutch (Feb 26, 2003)

so you adjusted the idler wheel lean? did you twist the left-side yoke?


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## Ray.Klefstad (Oct 7, 2006)

nccrutch said:


> so you adjusted the idler wheel lean? did you twist the left-side yoke?


Yes. I tried adding and subtracting turns to each side to see what made the tear improve towards a bullet hole. I would shoot two bare shafts after each change. When I got close to bullet holes, I switched to half twists. Then got perfectly round holes with bare shaft. Then I tried a fletched shaft and point was right in the center of the vanes.

I find the tear made by the bare shaft much easier to read than that made by a fletched arrow.

Ray


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## Relentless (Jul 20, 2007)

80% of those bows come out of the box neededing a twist or so in the left yoke.


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## Ray.Klefstad (Oct 7, 2006)

Relentless said:


> 80% of those bows come out of the box neededing a twist or so in the left yoke.


You are right on Relentless. The new Switchback needed about 2 twists tighter on the left yolk string, then it was good to go. I would think the Mathews dealer would have known this and just made the adjustment himself. Perhaps it takes too much time to press, adjust, shoot, repeat. It took me two hours doing it myself. I'm glad now because I learned something new and can now adjust the cam lean on all my bows. 

Ray


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## Relentless (Jul 20, 2007)

we ALMOST literally pull them out of the box and put two twists in the left yoke...But glad I could help you out. Happy shooting.


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## WEATHERBY460 (Dec 24, 2002)

I have a dxt and would like help checking cam lean. I am getting a bad left tear. How do I do this, and which cable is considered the left yolk


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## MtnHunter (Feb 7, 2004)

So on a left hand bow you would twist the right yoke?


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## Lonestar63 (Mar 19, 2007)

Guys, the following is from Vince over at MathewsInc. Great website for working on these bows. He may have it posted here on AT as well. This is how i set all my bows idlers.........

There has been much discussion about ATA and setting it properly. I have had many bows that needed tuning and one thing I have noticed is that rarely is there any consistency in how the idlers are aligned. This is due to the cable harness settling after the initial setup. Every single bow that I've tuned has exhibited excellent flight characteristics with the following method:

I max out the limbs to take my spec measurements. I press the bow and take the cable loop and twist until the ATA measurement on the shelf side corresponds to the following specs:


29.75" for the DXT
37" for the Drenalin LD
33" for the Drenalin
31" for the Switchback XT
33" for the Switchback
31.5" For the outback

Once this is set with the limbs maxed out I look at the cam to see where it's orientated. I adjust accordingly until the timing holes run parallel to the bowstring putting equal twists in both loops of the string to maintain the balance of the factory twist. After this is done I set my nocking point so the arrow sits perpendicular to the string. I then set my centershot to 13/16" at the berger button.*

Once this is accomplished I run an arrow shaft flush with the bow arm side of my idler wheel. I then twist the cable harness so that a gap of a light 1/8" exists between the shaft and the string at the nocking point. (see pic)* At rest the idler is canted inward from the riser on the top and outward at the bottom but at full draw it's straight up and down.











Every one of these bows that I've tuned like this has had excellent results. From this point, walk back tuning is a great way to dial in centershot to an ever greater degree as well.


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