Speed loss

[jrock]

I have a questions for any bow tweakers on the site.

I have an insanity CPX, love the draw on it and it shoots awesome. I've had the bow for going on three years now. Bummer thing I've noticed is that I lost about 12 fps between year 1 and 2. Just put new Vapor Trail VTX strings on with bBwjax string sleeves instead of speed nocks (awesome Bowjax product BTW) and once the bow was in spec, I had no speed change. Didn't expect to with just a string change but the bows was out 3/16" on ATA and was hoping that brining it back into spec would fix it. You know, increasing the preload and all.
I don't have a scale to measure the draw weight and Bowtech just says to take it to a dealer. I'm thinking it is limb relaxation. Thus I would have to shorten the ATA below spec to get the 70 lb draw weight back. As you all know in long range bow hunting, 12 fps is a big difference. Any thoughts before I contact bowtech again?

 

[dk260]

I'm having a hard time following you... At what time (after what change) did you notice the speed loss? I imagine you know this already, but check ATA and Brace height along with keeping the cables dead center in the timing marks before you call it in spec.

 

[jrock]

I noticed the speed loss near the end of my second season with the bow as I had to progressively adjust the pins.
I have it set up now with the ATA 1/16" short on one side and 1/16" long on the other so average is 32". The cams are synced by draw stops and are within the timing dots but about 1/32 off of dead center. I have a 28" draw.
I am going to put a couple twists into the cables tonight to make the longest ATA measurement 32" and see what happens. Thinking of just shortening the ATA until I get back to the original speed. Brace height is spot on. I did contact Bowtech and they said if the bow is in spec and shooting slow to have a shop send it to them to get it evaluated.