Fine tuning bowtechs overdrive binary cam

[bowtech experience]

I just got the new experience and have been messing with tuning it for a few days. I been having a lot of trouble getting it to broadhead tune, so I just kept twisting the yokes the way they say to twist them and I got my broadhead and field point touching each other out to 50 yards but my center shot is a little bit out and my cams r leaning one a lot worse than the other one but my timing is perfect when I am full draw. I just wanna know if this sounds ok I mean if it's shooting bullets out to. 50 with fix lades it should be good right ? Well image perfectionist and something don't feel right with nothing being set the way I'd tune any other bow. Has anyone else broadhead tuned this bow? Mine is 29 in draw 70lb. And should I try to get my cams both leaning the same amount? Or leave it be since it's shooting so good. Also what arrows did you guys use off this bow if you shot it? Thanks a lot

[demontang]

I jave an insanity cpx and have noticed it like a little cam lean toward the riser. You should have both cams leaning the same. Your center shot should be set by measuring it so your arrow rest the same at the front of the riser as the back. If you have a lot of cam lean look at your form and make sure its not you causing the bow to need more lean. The bowtechs dont tune like other bows set your center shot then your cam timing then paper tune and make sure you twist the yokes the same twist in oneside twist out the other and on each end of the bow so you keep your cam timing.

[Jellymon]

Those bows  should tune easily down the center using the yokes. To get the best answers we need more numbers. Arrow spine and length. Point weight. With your poundage and draw length I would shoot .300 spine arrows. And yes both cams should be leaning equally and look like this at rest from behind the bow in shooting position. Top-\   Bottom-/. just not that much. 
                                                                         
If you lay an arrow on the left side of the top cam the arrow should just touch your knocking point, or point at it, somewhere in that range.

If you're planning on hunting late season I wouldn't touch it til after the season if broadheads and field points are together at 50. 

[bowtech experience]

ok thanks guys, i think i will leave it alone for the rest of archery season then i will mess with it more, the arrows i have now are to stiff because they were for my 80lb monster, so it could have alot ot do with that to i just ordered some new arrows so when they get here i will make sure its still in tune with them. i figured both cams should be leaning the same amount so i will have to fix that. oh and for my center shot i did set it all dead even when i started and after twisting my yolks to move my string, now my knocking point is just a hair out but thats what it wants i guess. ive just tuned a lot of bows and they didnt have the center shot out and they didnt have cam lean when i was done, so this bow just had me all confused. could someone tell me why it is that the cams should be leaning like that? ive shot mathews my whole life sp i dont know anything about bowtech until now, but im figuring it out. the speed im getting through my chrono is 296fps and thats with a goldtip 75/95 which i know is to stiff and heavy for this bow. before i tied in my kisser and knocking point i was getting 299. im hoping with lighter arrows i can hit over 300, also im using barred feathers in right wing with a right offset when i fletch, you guys think i should go to veins? ive always loved feathers but with my monster they were all i could get to tune because the veins hit my cables when i shot them off it.

[Jellymon]

These bows need pre lean because of the amount of pressure on the roller guard. Since the roller guard is off to the side and doesn't slide backward like a slide, there is a ton of pressure on the roller.  When you draw the pressure on the cables tilts the cams over, so the only way to get them straight at full draw is to have them leaning slightly at rest. Bowtechs flex guard helps this some, but you will still get some torque. As for the arrow spine those 75/95's are .340 spine.  If anything they will be slightly weak, not stiff. They would be very weak out of an 80lb monster. How long are those arrows? Point weight? What does your centershot measure from riser to center of arrow?

[RadSav]

No bow should ever need to be tuned with cam lean.  Period!!!  Some bows have cam lean that is impossible to get rid of without completely messing up the function of the bow.  And for those bows cam lean should be set to minimal and then tuned for proper center and timing.

The Experience likes an arrow slightly stiff.  Very common amongst bows with perfect cam, riser and grip location.  If you are even close on an Easton chart go with the stiffer shaft selection.  Same goes with almost all PSE bows.  Archer's Advantage is the very best way to match proper spine.  The large cam, high pre-stress and ultra light limbs of the Bowtech pickle fork risered bows and the PSE bows function very much the same.

So if there is any lean to the cams of your Experience, Invasion, Insanity, etc. at full draw get it back to straight.  Then time the cams into perfect sync.  The plunger hole on these bows is located approximately 5/8" above center.  So at perfect sync the bow is really trying to put perfect balance of pressure on the arrow nock when shooting basically off the shelf.  Assuming the riser is completely rigid, the limbs are perfectly balanced and the cams are perfect mirrored images of one another. So you need to move the vertical pressure balance (or timing center) up to where you have the rest and the center of the arrow.  You do this by delaying the lower cam or advancing the upper cam.  If you had both cams in perfect sync this should be able to be done by a simple tiller adjustment.  But it can be done with a simple L/R balanced adjustment to the yoke as well. 

If you are supremely anal about things you can use a tuning/tiller board.  However, I usually do it by feel with my eyes closed.  You simply close your eyes and draw the bow back very slowly trying your best to feel the cams break over the let-off wall.  If you are not at center you will feel two things; #1 - a double break over as one cam goes and then the next.  #2 - the riser will rock up and then down or in the reverse.  Adjust until the break is as short and precise as you can get it and the riser stays solid through the let-off/break over.  Once you have reached that point you should be at the vertical center of thrust even though your arrow is not at center with the bows true center.

If your D-Loop was installed correctly your release should find it's way directly behind the arrow nock as you draw.  If it is not you may need to place your arrow rest or nock set slightly above or below the true 90 degree of the arrow/string.  Then set your arrow rest for perfect center shot with a good stiff arrow and you should be ready to rock and roll with perfect arrow flight regardless of point.  Assuming you do not torque the bow as it is drawn or shot.  Since no one is a perfect shooting machine and all our hands are created different a minor adjustment to the L/R on your rest may be necessary.  But I do mean Minor!!  If it takes more than a minor adjustment you will want to play with the poundage, arrow length or tip weight to adjust the spine of your arrow.  If five pounds of draw weight does not change things you need to loosen you wrist strap, relax your hand, open up more to the target, work on capital "T" form or some other form related issues you may be having.  Draw length will effect hand torque too so be sure to check that also.

The Bowtech Experience has been one of the very best tuning bows I have ever shot in my life.  If I were to design a bow myself there would be very little about the Experience I would want to change.  It's about as perfect a bow as I have seen available to the public.  And it may be the only $1,000 bow I might agree gives performance and shootability equal to the price tag.  For myself, that is saying quite a bit!

Good luck in getting that bow dialed in perfect.  If after the season you are still having problems send me a PM.  Perhaps I will have the test area put back together and I can do a Hooter tune for you.

[bowtech experience]

thanks guys and ill get that measurement when i get home. and as for the arrows i always thought that 75/95 ment that they were for that poundage, was i way off? the arrows i just ordered are 55/75 so they are going to be way to weak of spine huh? i have me 75/95 cut short to where my broadhead is about to my rest. the wheels dont lean when i am at full draw they are straight then but when its not drawn is when they lean in and i understand why that is now. as for the center shot though i will measure it up in a couple hours when i can and ill post up what i get

[bowtech experience]

as for form and stuff like that im good to go i have great form and no wrist strap and my grip is not tight on the bow its a relaxed grip. so im thinking might be arrows or maybe they are fine and i need to mess with the wheels a little bit more to get it tuned out to 80+ i dont plan on shooting deer that far but id like to know i could. whats the exact arrows you guys would recomend for me with a 100 grain point, that being becaus ei have so many broadheads in 100 gr

[RadSav]

What length feathers?  You say you draw the arrow all the way back to the rest.  So I assume they are shorter than the 29" draw length.  What length are they cut to?

[bowtech experience]

4 inch barred feathers and the arrows are just about 28 and a half long. i checked my center shot and it is for sure out some, not a ton just a small amount. and as for my cams one of them is leaning more than the other one so im thinking of starting tuning all over again just moving everything back to close as i can and start broadhead tuning again. i mean they are shooting pretty good and it took me 2 days to get them to hit that close i just had no idea the bow would look so outa wack when i did get good arrow flight. also what it is that i had so much trouble getting out was that the arrow with the broadhead kept hitting right which could be weak spine and i just told myself theres no way they are to weak when they are for a 75 to 95 pound bow but i guess i was wrong maybe

[Jellymon]

Also keep in mind that if your struggling to tune, and broadheads hit right of field points with everything where it should be, that is a very good indicator that your draw length is too long. Even 1/4-1/2" too long can make broadheads go inches right of field points. This is assuming that spine and form are correct. That bow has rotating modules so draw length would be a free, easy thing to check.

[bowtech experience]

thanks guys and jellymon when you said to lay my arrow on the side of my cam where should my knocking point be on that arrow? on the opposite edge or centered on it? and is the same for both cams?

[Jellymon]

thanks guys and jellymon when you said to lay my arrow on the side of my cam where should my knocking point be on that arrow? on the opposite edge or centered on it? and is the same for both cams?

If you have zero lean at rest, the arrow laid on the left side of the cam will parallel the string with about a 1/32" gap between the string and arrow, like railroad tracks. When you add a half twist to the left yoke and take one out of the right the cam will now tilt and the arrow will get closer to the string. Most setups I've tuned had the best results when the arrow just touches the string at your knock point , to the arrow pointing at your knock point. The lean isn't very much and is hard to see without the arrow to show you. It's best to start out with both cams perfectly straight, with arrow parallel to the string, and adjust equally as you go.  That way you know both cams have the same lean at rest.

[Jellymon]

Here's how it looks on my bow. See how the arrow points at my knock point? Hoyt's tend to need a little more so yours might not be that far. More lean than that to tune it then you have another issue, most likely arrow spine or draw length.

[bowtech experience]

ok thanks and i think i may just put them straight and start again but as of now i put the center shot back to being dead on then i tried to even the cams out as much as i could by eyeballing it and with an arrow then i made them both slightly lean so that my arrows sat just like in your picture maybe not even that much and i shot it again, and its damn close but not perfect so ive put three twiist in the left side of both yokes and they r now leaning in but one is leaning more than the other one somehow (i musta not got it dead on from the start im guessing) anyway its real close again so i might start over again or leave it depends on if the wind lays down outside its brutal today

[bowtech experience]

ve you evm move more that the other when you r twisting them both the same amount one the same side? i twisted on my left side of bow because my broadhead was right and one cam leaned more than trhe other one did but it seems to be shooting ok. i just want this thing to be perfect. i drive people nuts with the way i am about this stuff haha

[Jellymon]

Three full twists or half twists? Like I said, if you need more lean than my pic than it's another issue. If you go further than 2 full twists into the left and two full out of the right, then you risk derailing your bow

Two easy tests. Set your lean close to my pic. Set centershot 13/16" to 3/4" from riser to center of arrow. Then if broadheads are still right of feild points.......

1. Lower your poundage five pounds. If broadheads get closer to field points, then you know your spine is off. Get stiffer arrows.

2. If that doesn't work then I can almost guarantee that your draw length is too long. Drop it 1/2" until your broadheads move to your field points. Within reason, too short isn't good either.

Again this is assuming good grip and proper form. Good luck.

Also keep in mind that your knock point isn't in the center of the string, it's closer to your top cam then the bottom. So if your measuring both from the knock point it's going to look different. The arrow should touch the string equal distances from each cam lobe.

[bowtech experience]

thanks alot guys you helped me out for sure. i got my bow firing bullets now and my center shot is perfect and my knocking point is dead level i have the cams very close to being the same amount of lean and my broadheads and fieldtips are hitting so close together i just moved back to 60 and shot my broadhead and then my fieldpoint and my fieldtip took one of my muzzy fixed blades right off it hit so close. so tuned to 60 yards is good enough for me, i was going to try further but its to windy. thanks again guys. and i am now a believer in the overdrive binary cams i got this bow tuned alot better than i ever got my old monster

[Jellymon]

Sweet! 

How much pre lean did you end up with?

[demontang]

Good to hear. Im shoot 300spine since 75/95 where to weak, these bows a great to tune and will flat shoot.

[RadSav]

For that bow, draw length, arrow length and poundage you do want to have a 300 spine arrow.  7595 or 340 spine arrows would need to be shot at 60# to get proper spine.  I shoot mine at 62# with 27.5" 340 spine arrows to hit optimum spine.  You have proper FOC now with the 7595's, but that will be lost if/once you step up to the Kinetic XT 300's.  You will probably benefit from changing to a 125 grain point at that time.  Will put you at about 11% FOC.

[bowtech experience]

thanks guys, i really like this bow and its at 68lbs and shooting 297fps now and alot easier to shoot than my monster, my monster was faster but ill give that up for this amount of accuracy. i was smacking arrows all evening yesterday even out to 70 so my bow is tuned great for these arrows so im using them the rest of the season. now i ordered gold tip XT hunters in 55/75 the other day, so im guessing they will not be stiff enough for my bow? should i just resell them when they get here?
   jellymon, my cams are not leaning to bad at all now, they are about like yours but not even that much tilt so i am really happy now, and my center shot is right down the center to. this will be my first hunting season in 4 years that i can use fixed blades, and i hate expendables lol so im a happy camper right now. im really glad i found this sight. when i ask questions like this at the local bow shops they look at me like im retarded and say you cant make a broadhead and field tip hit together out past 30, well BS i know i can i tell them. so i was starting to think i was the only one who really fine tuned until i started reading online. im going to try out them 3 blade bloodrunner heads and see how good of a hole they put through a deer. well thanks again guys, i really appreciate all the help.

[RadSav]

If mentioning expandable/mechanical heads on this thread it's always a good idea to remind guys you are not hunting in the Northwest.  Otherwise the internet police will have you arrested

My good buddy Del called me this morning from Connecticut.  He said on the way to his stand he saw a number of bucks trailing does.  My brother killed a serious masher in MD a few days ago as he ran a scrape line.  So it looks like your rut is full on now!  Good luck and be sure to share some pictures with us

[bowtech experience]

Haha yea I never thought of that. And yea our rut is starting to get real good I'll be in a tree all day today after 11a.m. I hope to get to try my new bow out this week on a big old buck

[RadSav]

Save some for my nephew! 

[bowtech experience]

haha will do and do you got a picture of that maryland buck?

[Jellymon]

Good Luck!