# Cam timing for Maxxis 31 w/ xtr cams



## ssmojr (Jan 14, 2007)

Alright Hoyt guys, I bought my first Hoyt and have some tuning questions. First, what are you using for reference holes or marks for the at rest location on the xtr cams? I have read and read and read and read, and you get the point. I have been thru a ton of pages from Javi, and it all sounds great but I do not know where the cams should be at rest. I would like to get this bow tuned nicely before turkey season so I want to understand everything I can. I have always draw stop timed, but I am a little confused. If I sync the cams at rest and then make adjustments for the draw stop timing doesnt that make the first "sync" a waste of time. By adjusting for draw stop I have changed the at rest. Please try and help me understand everything so I can do it correctly. I am a little slow sometimes. Ok thats not true but I really want to understand instead of just guessing I am alright. Thanks in advance guys!!!


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## ssmojr (Jan 14, 2007)

Second, I assume I would be doing all of this with the draw length and module I will be using, slightly different from the older cam and a half?
And again, flood me with information, I really want to be comfortable with what I am doing. Thanks


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## varmintvaporize (Feb 9, 2010)

I think you are confusing yourself the same way I did when I started messing around with the cam.5 systems. One thing that took me a while to get my head wrapped around, and unexplained by many people: The position of the D-loop (higher/lower) will totally effect the sync of the 2 cams. Because of this, it is very critical to start with the D-loop in the correct position for the rest/arrows you are using. If you draw the bow from above and then below the current D-loop postion you will see cam sync change. Once you see this it should make more sense to you. 
Before seeing this happen I (probably like most people) would move the rest up or down to square the arrow to the string, mainly because moving the D-loop can be a real PIA. Now I will move the D-loop and then sync then cams. 

I hope this helps you!


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## BowKil (Mar 19, 2005)

Here's what you do; First, make sure that you make all adjustments with the bow at it's max poundage. Turn the limb bolts in all the way (you can back them out a 1/4 turn if you want), but make sure that the poundage is where it's supposed to be at it's max. Set your rest height and nock point (you can do your ceneter shot now or later). You have to set (synch) the cams at full draw. The draw stop peg will be in the appropiate position (hole) in relation to your DL mods. If you have a draw machine/board it very helpful here. At full draw, you want your draw stop on the top cam contacting the cable at the same time (or like most prefer, the top cam advanced about an 1/8" or so before the bottom cam), meaning that the top cam draw stop is contacting the cable and the bottom draw stop peg is about an 1/8" away from the cable at the same time. Once your cams are timed properly at full draw it is irrelevant whare the cams are at brace. Don't worry about it. \


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## ssmojr (Jan 14, 2007)

First off, thanks for the info. 

I have been draw stop timing for a while on the PSE's I have owned, so I am pretty comfortable with that. But I still have some confusion. Just so everyone is aware I am asking questions based on Javi's thread. Everyone seems to be very confident in his abilities. Who am I to argue, so the questions are based on his theory.

1. I keep seeing there is a difference between in sync and draw stop timed. What is the difference? I really do not understand the "sync" idea.
2. Why is this done at max poundage? 
3. What if the tiller is off at max poundage? Would this imply the cams are out of sync?
4. He says that the string is just along for the ride to adjust ata with the buss cable. I thought the string controlled the ata and poundage. 

If you can answer any or all please do, I am OCD when it comes to understanding something I am trying to do. So the more information you can supply the better.


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## varmintvaporize (Feb 9, 2010)

The pictures posted above by BowKil show "Draw Stop Timing" very well

I had "Sync" explained to me like this:
Cam.5 system uses 2 cams that are NOT mirror images of each other. The bottom cam is the control cam, and the top is the slave cam. The nock & rest points are not halfway between the 2 axles and they are above center. In order to keep the arrow shaft 90 degrees to the rest/riser, from brace to full draw the 2 cams have to rotate at slightly different rates. Once you find the point at which the arrow shaft stays 90 degrees throughout the draw cycle, the cams are in sync.
Now the battle is to get the cams in sync along with the draw stop timing (which Javi explains very well) all happening together. Keep in mind changing one will change the other. Once you get both of these things to happen all at the same time, that baby will really shoot well.


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## fletched (May 10, 2006)

BowKil said:


> Here's what you do; First, make sure that you make all adjustments with the bow at it's max poundage. Turn the limb bolts in all the way (you can back them out a 1/4 turn if you want), but make sure that the poundage is where it's supposed to be at it's max. Set your rest height and nock point (you can do your ceneter shot now or later). You have to set (synch) the cams at full draw. The draw stop peg will be in the appropiate position (hole) in relation to your DL mods. If you have a draw machine/board it very helpful here. At full draw, you want your draw stop on the top cam contacting the cable at the same time (or like most prefer, the top cam advanced about an 1/8" or so before the bottom cam), meaning that the top cam draw stop is contacting the cable and the bottom draw stop peg is about an 1/8" away from the cable at the same time. Once your cams are timed properly at full draw it is irrelevant whare the cams are at brace. Don't worry about it. \


Hey bowkil, I see where you suggest maxing out the poundage first before making any adjustments. Is there a reason for this? I understand that putting the bow in spec should be done at peak poundage like ata and bh. After that, I would prefer to set the poundage where desired and then set the timing, draw length and nocking point. Things can change when the poundage is moved. I am just curious and mean no disrespect.


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## BowKil (Mar 19, 2005)

fletched said:


> Hey bowkil, I see where you suggest maxing out the poundage first before making any adjustments. Is there a reason for this? I understand that putting the bow in spec should be done at peak poundage like ata and bh. After that, I would prefer to set the poundage where desired and then set the timing, draw length and nocking point. Things can change when the poundage is moved. I am just curious and mean no disrespect.


The only thing that might change a liitle would be the nocking point depending on how much you turn down the poundage, but the timing should still remain the same. If you do need to move your nock point say an 1/8" or so, it won't be enough to make any cahnge in the timing.


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## dwagoner (Sep 27, 2007)

yeah its kinda a PITA to learn these really well, im still learning alot myself, but i understand them and can tune them pretty well, i would hope so after having about 5 cam 1/2 bows LOL and like VARMINT said the sync and timing are the objective to get working together


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## ssmojr (Jan 14, 2007)

Ok guys, I dont want to sound dumb here but I still dont understand the sync. This is what I would normally do, you tell me what is different. All of this after new strings, so the ata, bh and draw and poundage are all very close to spec. I said close because I have never tried to nail them down to exact numbers. If I am within a 1/16 or a lb or two, I do not take it any further. At this point the cams appear to be the same. With out an actual timing mark to measure from I cant be sure. From here I would adjust tiller to be sure it is the same. Then set rest and loop. Then draw stop time. From there I start the tuning process. I start with paper( I know some do not) then move to the walk back tuning. 

What about this is different than what I am reading in Javi's thread? And what is the deal with doing this at max poundage?


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## JPHI (Dec 24, 2009)

You want the bow at max poundage because the changes you make to the buss cable control poundage as well as ata and you are trying to get the bow in spec.

There are two lines on the bottom cam on the XTR cam & 1/2 and your limb should be within them at rest.


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## ssmojr (Jan 14, 2007)

JPHI said:


> You want the bow at max poundage because the changes you make to the buss cable control poundage as well as ata and you are trying to get the bow in spec.
> 
> There are two lines on the bottom cam on the XTR cam & 1/2 and your limb should be within them at rest.



Makes sense on the poundage. Now I am a little concerned because both of the lines you are speaking of are above the bottom limb on my bow.


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## JPHI (Dec 24, 2009)

I started by measureing my new strings and cable to make sure the were to spec. When I put them on things were very close. I was dead center of the cam marks with the lower limb. I was slightly short on ata, about 1/8 if that and about 1.5-2 pounds heavy. I adjusted the buss cable and the bow weight and the ata were good to go. I put the bow on the draw board and needed to untwist the contol cable 2 turns to get the draw stops timing and it was done. If your strings and cable are correct lengths to start out with you should be close to spec.


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## ssmojr (Jan 14, 2007)

I pulled all of my strings and they are all dead on the listed lengths. My top cam is over a half inch away from the cam when the bottom makes contact. I have never seen one so far off. Is this fairly common? All of my specs are very close. They are also way off at rest.


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## ssmojr (Jan 14, 2007)

I adjusted the buss and control and have the two stops hitting pretty close, the cams are not even close at rest. I hope this is ok. the berger hole seems very high on this bow. this is my first hoyt is that pretty normal for most of the hoyts?


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## ssmojr (Jan 14, 2007)

got everything pretty close and everything else setup today. even got to fire a few arrows. Not completely tuned yet but this bow is very nice. quiet, zero hand shock. the only noise I hear is the string stop. I have seen a lot of these changed out may have to do that myself. 

the cams are good at draw and not even close to each other at rest, seems weird but I think it is good. The tiller seems a little weird as well, it is a little different from side to side.


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## JPHI (Dec 24, 2009)

What do you mean by cams not close at rest? They are no identical cams. Are the lines on the bottom cam lined up with the lower limb? My upper cam doesn't have marks so I figure if my ata, bh, poundage, tiller, draw length and cams are timed I'm good.

When you say pretty close what does that mean?


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## ssmojr (Jan 14, 2007)

They seem to sit completely different in the limbs. . I know the cams are not the same, I guess I just thought they may resemble each other more than they do at rest. Right now the lower line on the bottom cam sits just a hair above the top of the bottom limb. All specs are good. I havent fine tuned anything. Top stop still hits a hair before the bottom, would like to get them the same. Havent done anything micro with the rest. I couldnt resist getting a couple arrows thru it.

I will post some pics tonight.


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## hrtlnd164 (Mar 22, 2008)

ssmojr said:


> I pulled all of my strings and they are all dead on the listed lengths. My top cam is over a half inch away from the cam when the bottom makes contact. I have never seen one so far off. Is this fairly common? All of my specs are very close. They are also way off at rest.


Make sure that your draw stop peg is in the correct hole. If you have C mods itmust be in the C hole.


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## ssmojr (Jan 14, 2007)

hrtlnd164 said:


> Make sure that your draw stop peg is in the correct hole. If you have C mods itmust be in the C hole.


B mods and in B hole. Thanks for the suggestion. It took some twisting and untwisting but I have them dead on now. I cant believe someone was having much luck with a bow that far out.

Gonna try again tonight for the pics.


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## YZ125MM700 (Dec 30, 2009)

I still dont understand how you tell whether the cams are sync'ed is correct or not, anyone care to explain again?


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## Lowedog (Apr 7, 2007)

OK, I am scratching my head here. I took a Maxxis 31 on trade. It ended up having a splintered limb so I got a new set of limbs out of the deal. In the mean time I also didn't like the after market strings that were on it and scored a brand new set of OEM string and cables. I just got it all back together. I pulled the string and cables and measured them to spec and installed. Top cam is around a half inch behind bottom cam at full draw. Cams are XR3 and mods are XR3C with string stop in C. I untwisted the CC 2 twists and didn't gain much. It appears to not have many twists left in it. My bottom cam doesn't have the lines others have mentioned. ATA is 31-1/8" and brace is right at 7". Haven't checked DL or DW yet as I wanted to get timing closer first. 

Any suggestions?


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## Robert43 (Aug 2, 2004)

Hi get all 3 strings to correct length 1st of all. Then if the top cam hits 1st twist up the controll cable , if the bottom cam hits 1st twist up the buss (Y) cable.
My Maxxis 35 dosent have marks go off the draw peg but make sure its in the right hole ie if you have c moduels it goes in the c hole on the bottom cam


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## hrtlnd164 (Mar 22, 2008)

Guys, in Javi's thread on draw stop timing he says in about the 4th sentence down that he uses tiller as a guide for the synch. These systems are very simple once you learn them. Set your draw stop timing as described and everything usually falls into place. Once you are timed correctly check your tiller, if it's even you are good to go. These cams are not mirror images of each other.


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