Be careful about changing the idler wheel lean. My Ovation has a factory spec that includes idler lean that is not straight. The Idler straightens out as the bow is drawn to full draw. I was confused about that at first too when I saw that when I first bought that bow.
I don't know about the Dren because of the narrower limbs and general narrower geometry but you might want to call Mathews or check out their WEB site and/or forum to be sure you are not going to fix something that is not broken.
How does it shoot ?
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