# Newbie Needs Tuning help with Bowtech Invasion



## salzar21 (Oct 25, 2012)

I have had similar experience with my Insanity CPXL. You will find that when you put twists into the yokes this will probably also affect your timing, but the cables don't need to stay dead center between the marks. You will need to check your timing with a draw board, you can make one easily enough, there are videos on youtube, the main thing needed is a small winch. The timing marks on the cams are for initial setup, after yoke tuning and finalized timing they may shift; mine is dead center on the bottom cam but slightly advanced on the top cam, but the draw stops hit simultaneously at full draw. Instead of just putting twists into the one side of the yokes as stated in the Bowtech videos; it is better to make small adjustments by for example putting half a twist into the left hand yokes (for a left hand tear), shoot the bow, then take half a twist out of the right hand yokes, shoot the bow etc... My bow ended up with a lot more lean that I would like; when a powerflight carbon arrow is placed against the side of the cam the tip of the field point is 3/4" from the string at the nocking point. I contacted Bowtech to see if this was too much lean but they didn't reply. Finally I would say that I reached a similar situation when trying to tune my bow, and I decided to reset it and start from scratch. I found my strings and cables had stretched a lot, the ATA was 1/2 too long; you can set your ATA exactly by twisting the strings and cables prior to initial setup. Good luck.


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## wacker stacker (Feb 2, 2006)

As stated above half twist in left and half twist out of right so ata stays the same. I had a similar issue and it was my grip. I have to watch that I keep my wrist relaxed. Touching my index finger tip to my thumb seems to help pull things into place. I keep my wrist inline with my forearm so my thumb and my index finger up to the first joint my a straight Y. Hold arm and hand out like you are gonna grab someone by the neck or shirt, with knuckles at a 45 deg. angle and then touch finger tip to thumb.


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## threetoe (May 13, 2011)

My hunting buddy had a similar problem. He took it to a couple other so-called "Pros" only to have them mess it up worse.

Try calling The Bow'n'Arrow shop in San Diego.
http://www.bownarrowshop.com/

They fixed his in a blink and now it's a tack driver! Quite as a church mouse too.

619-443-5488

They are some of the top Bowtech tech technicians in the country.


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## Da Nooch (Jun 3, 2011)

Thanks for the info fellas. I'm gonna give it another shot today.


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## Da Nooch (Jun 3, 2011)

OK, think I got it! Rest is now dead down center of riser after minor adjustment. After taking a 1/2 twist out of each cable, the cables r dead in the middle of the timing dots. This is new...lol. I also took 1/2 twist out of bottom cam left yoke and added 1/2 to bottom right yoke. I shot a bare shaft bullet hole thru paper & a fletched bullet hole thru paper. Moved back to 15 yds and bare shafts & fletched arrows are touching (broke 2 nocks in 4 shots). Seems to be driving tacks now! Thanks for the help again guys!:thumbs_up

P.S. Wacker Stacker...Thanks for the thumb touching index tip on the grip. :thumbs_up


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## SARASR (Oct 30, 2009)

Go to General archery section few posts down is a sticky called 
"The Nuts And Bolts Of .....
Look for bare shaft tuning.

Oh just saw your post sounds like you got it have fun.

Now go shoot some broad heads and let us know what happens.


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## Da Nooch (Jun 3, 2011)

Thanks SARASR. Found it, and I will be printing that out tonight and putting it to use tomorrow. Shot FP, BS, & FBBH at 25 yds and I know Im definitely in the ballpark, but not quite where I wanna be sittin.


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## MortenKnudsen (Sep 30, 2012)

Hi Da Nooch,
Good you got it fixed, but I will tell this story anyway - I have experienced a similar scenario with my Insanity CPX and I also almost went crazy...
I got my bow in perfect tune, but kept getting left tears with Easton Flatline spine 340 - I tuned and checked and by coincidence I tried a Beman Hunter spine 300 - and guess what, the problem was solved!
It all came down to arrow spine!
If you are pulling 70# with Invasion and overdrive cams, and shooting Vap's with spine 350, I strongly advice you to try other stiffer arrows with spine 300!


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## Da Nooch (Jun 3, 2011)

That thought definitely crossed my mind, and I'm curious to see what will happen with that. I thought I should be good with the 350 spine VAPs. My arrows are cut pretty short at 27.25 inches so I figured they would be a lil stiffer. I'll have to give it a try. Hope I didn't waste any more of my hard earned mullah on the half dozen 350's I just bought & cut....LOL. I'll be tuning at it again today, but I feel like I'm gettin' real close. Thanks for the tip, I'll see if I can get my hands on a 300 spine VAP at the shop.


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## MortenKnudsen (Sep 30, 2012)

Hi - give me your drawlength, tip weight, insert weight, vane type and nock weight and I'll look it up in my arrow software


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## Da Nooch (Jun 3, 2011)

DL 27 inches, 100 gr tip, 33 grain insert, blazer vanes (3), standard Bohning F nock for VAP...6grains??? Thanks for your help!!!


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## MortenKnudsen (Sep 30, 2012)

Hi, 
It seems the arrows are fine with the spine 350 - because they are only 27"
Optimal spine is 0.341 so that can't be much better.
I bet the bow is out of timing/sync.
Try also the check for fletching contact at the launcher - I usually steal one of my kids chalk pieces and pulverize them and dip it on the launcher and then shoot to see if the fletching leaves any markings


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## Da Nooch (Jun 3, 2011)

Thanks for checking the spine for me. One less thing to worry about. I will double check again for fletching clearance, but I think I'm OK in that area. I defininitely made some serious progress in the last few days, and I think I might be ready to hunt after a few more range sessions. Bare shafts and broadheads are impacting a bit higher than F.P.'s, but only by an inch or 2 at 35 yds. Arrow flight is really straight at this point (B.S., BH, & FP's are all sticking straight in target). Might just need a very small nocking point adjustment. Gonna shoot again, before making any more changes... *Thanks Again for your help and advice!!!!!*


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## wacker stacker (Feb 2, 2006)

I had an issue where the bare shaft made a bullet hole in one position, but if you rotated it it wouldn't. I think some guys shoot each shaft bare rotated in different positions to where it shoots a bullet hole and then mark it and fletch accordingly. However i find that by 8 or 10 yards fletching will straighten the flight of an arrow shot out of an ill tuned bow so I think it gets to a point where i just say "good enough" since I shoot mechanicals.


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## dwagoner (Sep 27, 2007)

Da Nooch said:


> Thanks for checking the spine for me. One less thing to worry about. I will double check again for fletching clearance, but I think I'm OK in that area. I defininitely made some serious progress in the last few days, and I think I might be ready to hunt after a few more range sessions. Bare shafts and broadheads are impacting a bit higher than F.P.'s, but only by an inch or 2 at 35 yds. Arrow flight is really straight at this point (B.S., BH, & FP's are all sticking straight in target). Might just need a very small nocking point adjustment. Gonna shoot again, before making any more changes... *Thanks Again for your help and advice!!!!!*


im kinda wierded that bareshaft is hitting with BH shafts and FP are little lower. typically you would suspect BH to be the one off from a BS. Have you checked and verified all the weights on the shafts??? on the bareshaft did you add any weight in rear to compensate for no vanes??? i think thats possibly why there up with BH shots, but agree your just a tiny smidge adjustment in nockheight, would try to lower rest that tiny amount first and see how they group then. i would bet it gets closer for you


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