# Hoyt GMX lateral alignment...................



## liquidmojo (Dec 1, 2012)

Greetings :smile:

Just got a new GMX 25" riser and put my 5 week old 990TX (40# medium) limbs in and to my surprise the string didn't sit in the groove on the top limb. Bottom limb is fine.
So I followed the instructions and put more than 100 shots through it to bed the surfaces before adjusting the alignment.
I ended up having to move both washers for the dowel side (sight window side) to the other side.
The string now sits in the limb grooves no problem.

I know its not the limbs. Tested them in an old GM riser and was shooting them in a Radian riser.

Anyone had the same 'issue' with a straight out of the box Hoyt riser?

Cheers


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## Viper1 (Aug 21, 2003)

liquid - 

I've had more GMX risers that needed lateral adjustment than any other Hoyt riser on the market. That doesn't mean that other Hoyt risers didn't, just IN MY EXPERIENCE, the GMXs needed it more often. Not a big deal if the shims are enough to correct it.

Limbwalker had a thread a while back on how to check for lateral deviation and correct it and it's work looking at, but I just go by eye ball. 

Viper1 out.


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## limbwalker (Sep 26, 2003)

If you have the limbs lined up, that's just step 1 in the alignment process.

Step 2 is getting the string on plane with the riser.

That old thread is 'round here somewhere...


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## Neo888 (Feb 4, 2009)

Yep, i had exactly the same thing, good news is that i could adjust with this method with the washer movements to get the string on plane with the riser.


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## agillator (Sep 11, 2011)

limbwalker said:


> ...That old thread is 'round here somewhere...


Here 'tis. One of my more precious AT references.


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## Seattlepop (Dec 8, 2003)

What I have learned with the Hoyt dowel system is that the washer count has little to do with whether or not the riser or limbs are straight. I'm embarrassed to say how many Matrixes I own or have owned, but suffice it to say that all have passed every test suggested on AT for straightness. However, slight variances, I think we are talking about 000's of an inch, in the depth of the recess of the dowel drill-out where the washers sit, means that the center of the dowel can be off while the riser itself is perfectly straight. 

Before setting up any dowel system bow, check to see that the dowel dove-tail is centered before you attached the limbs. Early on I would attach limbs and curse them for not being straight and fiddled with washers ad nausea. In a couple of incidents the dowel itself was not centered with 2 (factory setting) washers and once adjusted the limbs were straight after all.


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## liquidmojo (Dec 1, 2012)

Thanks for the replies. a can of worms (for me) is now open. Ultimately I want this bow to be set up better than I can shoot it. If that makes sense lol
I guess I was taken aback the alignment wasn't 'out of the box' and what 'should' be a simple plug n play, was not. 
There's a bigger picture.

Thanks again. I really appreciate it.


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## Borderbows (Apr 4, 2009)

There are 3 planes a bow needs to be straight on. Limb bolts are one. Lateral is another. So far in Aircraft terms you have covered Pitch and Yaw. What about roll.

if you cant trust one then why assume the others are fine?


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## Seattlepop (Dec 8, 2003)

Borderbows said:


> There are 3 planes a bow needs to be straight on. Limb bolts are one. Lateral is another. So far in Aircraft terms you have covered Pitch and Yaw. What about roll.
> 
> if you cant trust one then why assume the others are fine?


The topic of dowels would only apply to yaw, so not sure what you are asking. Roll would be about twisted risers? (easy to check) and can the dowel correct that (no).


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## chrstphr (Nov 23, 2005)

the stabilizers take care of roll. 


Chris


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## Borderbows (Apr 4, 2009)

Chrstphr. Not on a limb pocket they dont.

Seattlepop:

why do you need lateral adjustment?

If you payed good money for a straight riser and straight limbs... would they not be straight?

so why would you want to be able to move a set of limbs to the left or right the string should run though centre?

There are risers out there that are not straight and the validation of the design is that it can be compensated for by left right alignment.
but thats assuming that its a left or right twist.
For example. how many people have wound there limbbolts tight down. put a set of limbs in and checked tiller. then swapped the limbs top to bottom to check again. thus checking if the limb packet angles are accurate.

if your limbs are say showing 3mm, then they should show 3mm if the limbs are the right way or wrong way up, if the limb pads are accuratly cut.
but that doesnt matter its ILF and you can adjust it to be "just fine".

ok, so there is a reason to get away with sloppy limb pad angles.
and a reason to get away with sloppy left and right.

so if there is small amounts of attention needed to these, why can you assume that the rotation is true.

why is this important?

well, because you can draw a COG dot on the ground. and move the leaning tower of piza left or right till its centre of gravity sits on that dot. but this doesnt fix its lean.

lets say you have a limb pocket thats not rotationally on the same plane as the other. Then you would adjust it so that it looked better. but the limb wouldnt track right now.

a far example which is Limb Walkers point, is a riser whos limbs pads are drilled spot on inline with each other.
but the limb pads are sitting at a crazy 45deg opposed to 90 deg to the beam of the riser.

This would mean that riser deflex would put the grip off centre. and the long rod off at 45deg to the bow (aka the limbs)

now, moving the limbs left or right to try and correct this would only mean both limbs would be showing out on the "over the tip" view, and pull off to one side when checked at full draw.
BUT line up at bH with the centre of the bow. You would have in effect 2 leaning towers of piza, to make up for it being out.

My View is dont assume 500 bucks gets you a straight riser. and dont always assume its the limbs that are twisted.

i have photo evedence of this exact problem as well as quotes on this very forum from experience people that risers are often not striaght...


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## Seattlepop (Dec 8, 2003)

Borderbows said:


> Chrstphr. Not on a limb pocket they dont.
> 
> Seattlepop:
> 
> ...


I’ll take “What is ‘It runs in all directions” for $100, Alex.

Answer: “When is an AT thread like herding cats?”

I think the topic of "Howz the pitch, yaw, rock and roll of your riser?" would make a good thread. Of course everyone wants a straight riser if that is your point. Its related, granted, but actually a little off-topic. We were discussing how to center the limb dowel when presumably we are working with a perfectly straight riser. 

Consider that my Matrix, for example, has a perfect “body”, i.e., the bulk of the riser before all the post manufacturing drilling and finish has occurred. The process of manufacturing the steel dowel itself, and the precision drilling that must occur in the riser where the dowel fits are subject to the same manufacturing variances as any other equipment maker encounters. 

Lets face it, we are not talking about micro-chips that are untouched by human hands. The drilled holes on this riser have both the main channel as well as counter-bored drillings and then there is the finish itself which can alter the measurements by 000’s of an inch. You get the point. 

On a riser with an infinite-adjustment design, such as PSE and others, less precision drilling is required since you have to center the dove-tail by eye. There are no drill-stops that can be defined as a factory standard. Perhaps they include marks to line up, a “This is the center for Dummys” line, but the point is you would be totally unaware of any discrepancies because your infinite adjustability escapes some scrutiny. And how good is your “eyeball”? Perhaps a better question is how good does it really need to be? I would venture a guess that if you took 100 X-Appeals and measured precisely how many screw turns, exactly, it took to center the limb block you would find some variation. Does that mean the riser body is not straight? Of course not. 

What, then, about risers that have no limb alignment adjustability? “Don’t have to, they’re straight out of the box” etc etc. I would suggest that sure, they are perhaps just as straight as my Matrix or the OP's GMX, but since they have no post production precision drilling, are they any better or have they simply escaped a major manufacturing process while transferring responsibility for minor limb flaws to the riser owner to pursue? 

Reminds me of a marketing strategy by Bic. Remember when the flame on a Bic lighter was adjustable? I don’t know who needs to torch their eyebrows while lighting a cigarette, but I digress. Bic figured out they could save beaucoup bucks by eliminating the adjustment feature, while of course not reducing the price. How did they market this? By declaring it: ”The new and improved Bic! Now ADJUSTMENT FREE!” 

I hope whoever came up with that got a huge bonus. Its pure marketing genius. Personally, on my perfectly straight riser I like having some adjustability. It helps correct those minor limb flaws we invariably encounter. Not yours, of course.


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## Chinese Tea (Mar 17, 2010)

Personal curiosity- on my GMX I noticed that the dowel is undersized compared to the hole in which it sits in. This is of course essential because the darned thing needs to slide in and out for adjustment.
However, the size difference meant that I could wrap 2-3 layers of clear packaging tape around the entire dowel in order to get a snug fit between the dowel and the hole.

Is it like this for other dowel risers?


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## Borderbows (Apr 4, 2009)

Seattlepop said:


> I’ll take “What is ‘It runs in all directions” for $100, Alex.
> 
> Answer: “When is an AT thread like herding cats?”
> 
> ...


my sole point is having lateral adjustment is not the key to fixing problems such as dowels not parrallel to the floor of the pocket.
or the floor of the pocket is not 90 deg to the body of the limb.

So having adjustability is not as good as you might think if the error is not in that plane.


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## limbwalker (Sep 26, 2003)

Chinese tea, it's not necessary to wrap the dowel. It gets pulled to the bottom of the hole when you string the bow anyway.


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