# my center shot is crooked... is there a way to tune it shootable?



## MissMary49 (Dec 8, 2005)

So this may seem odd, but I have noticed my bow's center shot is not straight. For the sake of the photo I have lined up the string with the bottom limb pocket, it carries to the grip, but as you track up the string path the riser is now leaning to the right of center. Spacing on axles are mirrored top and bottom, and they are mirrored (symmetrical) cams as well. It is a modular riser. I haven't really dived into this bow yet, but I am setting it up now.

I am wondering if anyone has a bow that leans a little, and if it is something that can be made tuneable to be consistent? or will it cause me problems?


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## nuts&bolts (Mar 25, 2005)

MissMary49 said:


> So this may seem odd, but I have noticed my bow's center shot is not straight. For the sake of the photo I have lined up the string with the bottom limb pocket, it carries to the grip, but as you track up the string path the riser is now leaning to the right of center. Spacing on axles are mirrored top and bottom, and they are mirrored (symmetrical) cams as well. It is a modular riser. I haven't really dived into this bow yet, but I am setting it up now.
> 
> I am wondering if anyone has a bow that leans a little, and if it is something that can be made tuneable to be consistent? or will it cause me problems?
> 
> ...


lousy photo. You have a peg board full of packages of bowstrings, and then a bow press also in the background.



So, your question is also very unclear. Centershot means the sideways position of the arrow rest. So, you think you have the sideways position for your arrow rest too close to the riser? So, you think you have the sideways position for your arrow rest too far away from the riser? A "bow that leans a little". So, you think your riser is BENT? A "bow that leans a little". So, you mean your cams are leaning a little, cuz you have a binary cam bow? If you are asking about CENTERSHOT for the arrow rest, THIS photo angle works MUCH better.



Bottom cam on the floor. POINT the camera lens STRAIGHT down. 2nd arrow is pinched tight to the riser, to provide a reference for DEAD straight ahead.



FOR STARTERS, I move the arrow rest sideways until BOTH arrows are dead parallel.


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## nuts&bolts (Mar 25, 2005)

MissMary49 said:


> So this may seem odd, but I have noticed my bow's center shot is not straight. For the sake of the photo I have lined up the string with the bottom limb pocket, it carries to the grip, but as you track up the string path the riser is now leaning to the right of center. Spacing on axles are mirrored top and bottom, and they are mirrored (symmetrical) cams as well. It is a modular riser. I haven't really dived into this bow yet, but I am setting it up now.
> 
> I am wondering if anyone has a bow that leans a little, and if it is something that can be made tuneable to be consistent? or will it cause me problems?
> 
> ...


Cannot see the ENTIRE bow in your pic, but SEEMS like you do not have any yoke cables, so I don't believe you have a BowTech OverDrive Binary cam system. If you have the usual NO yoke leg, binary cam system...then, your axles are not adjustable, so you cannot yoke tune, cuz you have no yoke legs. So, your ONLY tuning options, at least the only EASY tuning options, are to move the arrow rest sideways to get your "bullet hole" and tweak draw length. MOre difficult tuning options, would be to shim the top cam sideways, with non-standard cam sideways spacing.


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## MissMary49 (Dec 8, 2005)

Sorry for the mess, I guess I should have apologized for that ahead of time....
if you click on the pic it opens in a pic box, and if you click on that again it opens it in a new window which allows for zoom to get the full resolution, thanks for cropping but it seems that the cropped size of the image is smaller, and you cant see what im talking about. if you want bypass all the clicking i just mentioned then here is the AT link that allows you to one-click-zoom. http://www.archerytalk.com/vb/attachment.php?attachmentid=3335793&d=1449103430 

So you can see the bow string drifting from alignment of the riser. I know not all bows have risers that match the shoot string path, if you were to visually line up the shoot string from limb pocket to limb pocket (or what I am calling CENTERSHOT (because I was taught to visually line up the shoot string with the center of the limb pockets for dual cams, and only the bottom pocket for single cams, as a reference to where your arrow should be when installing a rest)), but I cant help but notice this is particular riser seems like a 'leaner'. 


your CENTERSHOT photos are very insightful, I have never seen or heard anyone do it that way, kind of like checking for camlean with an arrow. I'll have to see if it works. my only hesitation is what if a bow has a rounded or oddly shaped riser design that wont allow you to tape an arrow for a true parallel comparison? Also if I take the photos from those angles you fail to see the riser lean I'm trying to point out.

It is a binary system, I didnt include the cams because I didnt think that it was necessary because yoke tuning is out, and I was trying to focus on the path of the string in relation to the riser to focus in on what I was trying to describe. However in hindsight it would drive me crazy not to see the whole thing too if I had not seen the bow in its entirety yet. Perhaps I will re-take photos if it can help.

If my question was unclear, I will try to ask it again; If a riser seems bent or leaning (which I think mine is- if you want to confirm or disagree with that assumption please feel free), is it possible that it can still be used as a good shooter? Or will it fail to deliver a consistent shot? Will it be inconsistent in throwing a bullet-hole? Does anyone have experience in shooting with a bow in a bent condition?

**Most people have to carry around a dictionary of "Maryisms" until they get used to the way I describe things, so I hope you'll have patience and kindness when dealing with people who are reaching out and asking for help, like me.
Thanks!


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## nuts&bolts (Mar 25, 2005)

MissMary49 said:


> Sorry for the mess, I guess I should have apologized for that ahead of time....
> if you click on the pic it opens in a pic box, and if you click on that again it opens it in a new window which allows for zoom to get the full resolution, thanks for cropping but it seems that the cropped size of the image is smaller, and you cant see what im talking about. if you want bypass all the clicking i just mentioned then here is the AT link that allows you to one-click-zoom. http://www.archerytalk.com/vb/attachment.php?attachmentid=3335793&d=1449103430
> 
> So you can see the bow string drifting from alignment of the riser. I know not all bows have risers that match the shoot string path, if you were to visually line up the shoot string from limb pocket to limb pocket (or what I am calling CENTERSHOT (because I was taught to visually line up the shoot string with the center of the limb pockets for dual cams, and only the bottom pocket for single cams, as a reference to where your arrow should be when installing a rest)), but I cant help but notice this is particular riser seems like a 'leaner'.
> ...


Need a better photo. I don't believe your riser is "BENT" or "crooked". Need your bow with both limb pockets on the floor or carpet and then have the camera take a photo of the entire bow, from cam to cam. Just looking at your GRIP area, seems the top cam might be shimmed too far to the right.


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## nuts&bolts (Mar 25, 2005)

MissMary49 said:


> Sorry for the mess, I guess I should have apologized for that ahead of time....
> if you click on the pic it opens in a pic box, and if you click on that again it opens it in a new window which allows for zoom to get the full resolution, thanks for cropping but it seems that the cropped size of the image is smaller, and you cant see what im talking about. if you want bypass all the clicking i just mentioned then here is the AT link that allows you to one-click-zoom. http://www.archerytalk.com/vb/attachment.php?attachmentid=3335793&d=1449103430
> 
> So you can see the bow string drifting from alignment of the riser. I know not all bows have risers that match the shoot string path, if you were to visually line up the shoot string from limb pocket to limb pocket (or what I am calling CENTERSHOT (because I was taught to visually line up the shoot string with the center of the limb pockets for dual cams, and only the bottom pocket for single cams, as a reference to where your arrow should be when installing a rest)), but I cant help but notice this is particular riser seems like a 'leaner'.
> ...


Need a COMPLETE photo, that shows the top cam all the way to the bottom cam. No, your bow riser is NOT bent. The centershot is also NOT CROOKED. BUT, yes, your bowstring is not parallel to the long axis of the riser. So, your bowstring is tilted sideways like this ////////// when your riser is vertical like this |||||||||||. So, I have rotated your riser to dead vertical within 1/10th of a degrees. WOULD have been a LOT easier, if the photo had a blank wall behind your bow, and if I could see the entire bow, from cam to cam.



So, with your photo rotation corrected to 1/10th of a degrees, I added a vertical reference line parallel to your riser, and another line that runs along the axis of your bowstring. I added a triangle between the vertical reference line and the line that represents your bowstring. So, to show that your bowstring is CROOKED, tilting to the top right like this //////////....I copied the same size blue triangle between the vertical reference line and the bottom part of your bowstring. So, your riser is NOT BENT. So, your TOP cam has the FAT spacer on the LEFT side of the top cam, and you have the SKINNY spacer on the RIGHT side of the top cam. So, your BOTTOM cam has the SKINNY spacer on the LEFT side of the bottom cam, and you have the FAT spacer on the RIGHT side of the bottom cam. So, your CAM horizontal spacing is NOT mirror image. THat's all.

TOP of bowstring is farther away from the vertical reference line I added to your photo, so the BOWSTRING is what is crooked like this /////////////////.



BOTTOM of bowstring is closer to the vertical reference line I added to your photo.


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## nuts&bolts (Mar 25, 2005)

MissMary49 said:


> Sorry for the mess, I guess I should have apologized for that ahead of time....
> if you click on the pic it opens in a pic box, and if you click on that again it opens it in a new window which allows for zoom to get the full resolution, thanks for cropping but it seems that the cropped size of the image is smaller, and you cant see what im talking about. if you want bypass all the clicking i just mentioned then here is the AT link that allows you to one-click-zoom. http://www.archerytalk.com/vb/attachment.php?attachmentid=3335793&d=1449103430
> 
> So you can see the bow string drifting from alignment of the riser. I know not all bows have risers that match the shoot string path, if you were to visually line up the shoot string from limb pocket to limb pocket (or what I am calling CENTERSHOT (because I was taught to visually line up the shoot string with the center of the limb pockets for dual cams, and only the bottom pocket for single cams, as a reference to where your arrow should be when installing a rest)), but I cant help but notice this is particular riser seems like a 'leaner'.
> ...


So, what happens if the SPACERS are switched backwards on the TOP axle? The spacers are in REVERSE position, compared to the bottom cam spacers? Well, then your bowstring is leaning to the TOP right corner, and your bowstring is leaning to the BOTTOM left corner, like this //////////. Is a bowstring that leans sideways, going to make your arrow fly in circles, like a boomerang? NOPE. Is a bowstring that leans sideways going to make your arrows miss HIGH or LOW? Nope. Well then, WHAT happens when you make a bowstring lean to the right like this ///////////...? Your arrow rest centershot will move CLOSER to the riser. So, WHAT happens if you make a bowstring lean to the LEFT, like this \\\\\\\\\...? Your arrow rest centershot will move FARTHER away from the riser, to the LEFT. BUT BUT BUT, what happens if you shim the top cam, sideways, so that the bowstring looks like this ||||||||||...? Your arrow rest centershot will move somewhere in between. So, is this why folks buy shim kits from DBLlungit? To move the top cam MORE sideways LEFT? To move the top cam MORE sideways RIGHT? Yup. So, people move the top cam sideways with a custom shim kit (axle spacers) to CHANGE the sweet spot for arrow rest centershot, cuz there are no yoke cables to TWIST the limb tip on the top axle? Yup. BUT BUT BUT, will this BREAK my bow, if you install custom shims (axle spacers)...will this VOID my factory warranty...will working on my own bow VOID my warranty...will I shoot better if I shim my top cam from //////// to ||||||| for the bowstring? Yes, maybe, kinda sorta, possibly, hopefullly, potentially, and welcome to CUSTOM TUNING your bow, to see what happens.


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## tsilvers (Nov 16, 2002)

nuts&bolts said:


> Need a COMPLETE photo, that shows the top cam all the way to the bottom cam. No, your bow riser is NOT bent. The centershot is also NOT CROOKED. BUT, yes, your bowstring is not parallel to the long axis of the riser. So, your bowstring is tilted sideways like this ////////// when your riser is vertical like this |||||||||||. So, I have rotated your riser to dead vertical within 1/10th of a degrees. WOULD have been a LOT easier, if the photo had a blank wall behind your bow, and if I could see the entire bow, from cam to cam.
> 
> 
> 
> ...


LOL.. Mary.. the guy can not diagnose wether or not your riser is tweeked or bent from your picture.. Regardless of how many red lines and triangles he draws on it.. More than likely it is not bent but not out of the realm of possibility either.. And if it is a binary system.. the spacer washing from the factory would be the same on both top and bottom cams.. If different.. someone was playing with spacing..

One thing to look at and very well could be the culprit is the limb pocket.. sometimes excessive slop in the pocket to riser... or pocket to limb interface(s) will cause the limb to lean biased the cable guard side which is what i see in your pic... Back in the day we used to have to shim up "sloppy" limb pockets to avoid this very condition.. I cant tell from pic but is that an enclosed one piece pocket? Certain designs that dont use fully enclosed limb pockets have tendencies to lean or shift badly.. If it is what I think it is you are more than likely seeing it on this bow... Good luck..


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## tsilvers (Nov 16, 2002)

nuts&bolts said:


> So, what happens if the SPACERS are switched backwards on the TOP axle? The spacers are in REVERSE position, compared to the bottom cam spacers? Well, then your bowstring is leaning to the TOP right corner, and your bowstring is leaning to the BOTTOM left corner, like this //////////. Is a bowstring that leans sideways, going to make your arrow fly in circles, like a boomerang? NOPE. Is a bowstring that leans sideways going to make your arrows miss HIGH or LOW? Nope. Well then, WHAT happens when you make a bowstring lean to the right like this ///////////...? Your arrow rest centershot will move CLOSER to the riser. So, WHAT happens if you make a bowstring lean to the LEFT, like this \\\\\\\\\...? Your arrow rest centershot will move FARTHER away from the riser, to the LEFT. BUT BUT BUT, what happens if you shim the top cam, sideways, so that the bowstring looks like this ||||||||||...? Your arrow rest centershot will move somewhere in between. So, is this why folks buy shim kits from DBLlungit? To move the top cam MORE sideways LEFT? To move the top cam MORE sideways RIGHT? Yup. So, people move the top cam sideways with a custom shim kit (axle spacers) to CHANGE the sweet spot for arrow rest centershot, cuz there are no yoke cables to TWIST the limb tip on the top axle? Yup. BUT BUT BUT, will this BREAK my bow, if you install custom shims (axle spacers)...will this VOID my factory warranty...will working on my own bow VOID my warranty...will I shoot better if I shim my top cam from //////// to ||||||| for the bowstring? Yes, maybe, kinda sorta, possibly, hopefullly, potentially, and welcome to CUSTOM TUNING your bow, to see what happens.


What??


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## MissMary49 (Dec 8, 2005)

Limb pocket.. Ok that might be a possibility. Would I have to file down the riser then to straighten it? If that's the reason. 
I will take more photos for fun to help you all out. Thanks for the ideas.


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## gofor (Feb 4, 2013)

Short answer, OP: Unless the riser has been damaged to really warp it, yes, you should be able to tune it for good consistent performance. First step as alluded to above, is to determine what is out of kilter. Riser could be bent, spacers installed wrong, a seriously weak limb (probably requiring replacement) or limbs installed in the wrong sequence, bad bearing in top cam, etc. If you tear it down to check the limb pockets, you may want to look at the deflections stamped on the limbs just in case an odd ball was thrown in the mix.

Question: How does the top and bottom cam lean compare?

Second question: How does it shoot now?

Go


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## Ehunter42 (Mar 3, 2010)

Is it just me, or does Alan's vertical line along the riser on the bow seem to hit the inside of the bottom limb, and is heading towards the outside of the top limb? Almost looks like the top limb pocket is sitting out of square or something. On the enlarged pic, the top limb seems to be going off to the right of the bow. I had that happen with a Martin Onza III I had, but it still shot great. Was just a little more trouble getting it to tune in well. Mine didn't look quite as far off as this one though. Not knocking on Alan by any means, just something I noticed.


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## tsilvers (Nov 16, 2002)

Ehunter42 said:


> Is it just me, or does Alan's vertical line along the riser on the bow seem to hit the inside of the bottom limb, and is heading towards the outside of the top limb? Almost looks like the top limb pocket is sitting out of square or something. On the enlarged pic, the top limb seems to be going off to the right of the bow. I had that happen with a Martin Onza III I had, but it still shot great. Was just a little more trouble getting it to tune in well. Mine didn't look quite as far off as this one though. Not knocking on Alan by any means, just something I noticed.


Read my post above.. not an uncommon problem on certain rocker/pocket designs... some are worse than others and some aren't even fixable..


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## nuts&bolts (Mar 25, 2005)

Ehunter42 said:


> Is it just me, or does Alan's vertical line along the riser on the bow seem to hit the inside of the bottom limb, and is heading towards the outside of the top limb? Almost looks like the top limb pocket is sitting out of square or something. On the enlarged pic, the top limb seems to be going off to the right of the bow. I had that happen with a Martin Onza III I had, but it still shot great. Was just a little more trouble getting it to tune in well. Mine didn't look quite as far off as this one though. Not knocking on Alan by any means, just something I noticed.


Could be camera angle. Could be lens distortion. We cannot see the cams, so hard to tell if the camera lens is square to the limbs or not. If the camera lens is not parallel to the limb face, then you get keystone distortion.


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## Ehunter42 (Mar 3, 2010)

Good point. Your opinion is ALWAYS well taken by me Alan!


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## jgomes1992 (Jan 21, 2011)

Thank you for this post I was having the same problems


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## skidge (May 3, 2014)

which model is that. Obviously a martin with nito cams, Awesome by the way. None of my nitro cam bows had spacers that you could move i don't believe. I know my onza3 doesn't, the cam bushings fit tight to the limb forks. I wish they did have spacers tho. Other than timing and moving rest thats all you can do from a tuning aspect. I will say tho your picture does not look square with back of bow. I would unstring and see if there is any sideways slop in the roto cups


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