Hoyt GM limb pockets adjustment?

[Allvyn]

Hey everyone, I finally got my 2nd hand Hoyt GM and am loving everything about it from the feel to the minor scratches and chips. I am however unsure as to what the actual draw weight on the limbs would be when the limb pocket adjustments are set to it's lowest and highest.

Would I be right to say that with the marked 38 pounds 68inch samick universal glass limbs, the actual effective draw weight for the bow would be around 38 pounds at the lightest setting? My draw length is around 28 inches.

If that be the case, would it be safe for me to say that when set to it's heaviest possible setting, the limbs would have an effective draw weight at around 41.8 pounds? Read the Hoyt manual but it doesn't say much about this except that the limb pocket adjustment is around 10%.

Or is this a case of +/- 5% in which the draw weight can be altered to +/- 38 pounds with 38 pounds being the effective draw weight when the limb pocket settings are set directly in the middle?

Please help me out with this one, it's been running in my head for the past 2 days. It is my first bow afterall and I feel like a kid on Christmas morning, enthusiasm all over.

[BowSurfer]

Rated weight is at the lightest setting, then adjustable upwards by 10%. I have found that when adjusting you do need to keep a careful eye on tiller, and so if you had taken up some of the adjustment to get the till right at the lower weight, then you may not have the full range available and still be able to get a good tiller - depends on the limbs i guess.

[buzz lite beer]

The Hoyt GM as is the case with all Hoyt risers are set up so the middle setting should give you 38lb @ 28" as marked on the limbs, 8-10% adjustment available, taking you up to around the 40lb mark with maximum limb pocket adjustment and down to 36lb on minimum setting.

[Rik]

It's the limbs which determine how the weight adjusts, rather than the riser...
Hoyt limbs have their weight measured at the midpoint of adjustment, so you would get +- 5% on them.
Most other manufacturers weigh at the bottom end of the range so you would get +10% adjustment with them. There may be some limbs which weigh at the top end of the range, but I don't think any of them are Hoyt fitting...

But The limb measurements may be out by up to 1 pound and still be considered within spec. And different risers have slightly different ranges of adjustment. So the '10%' figure is a 'more or less' rather than 'exactly'.

Going back to your case... Samick universal limbs will be one of the '+10%' sort. Given that they are marked at 38lbs, they should have a weight between 37 and 39lbs. Should have. You can't rely on cheaper limbs having accurate marked weights...

Now draw length... I'm assuming you're measuring it to the AMO standard? That's to the pivot point (or button) plus 1.75". If you're measuring it to the button, then your actual draw length will be around 29.75", which might add about 10% to the draw weight...

Assuming the draw length is 28", you're looking at a bottom of adjustment range of 37-39lbs and a top end around 41-43 pounds. But YMMV.

This is why we always advise people to weigh bows, rather than calculating the draw weight. Calculations rely on too many assumptions.

[Allvyn]

Incredible and very informative Rik, thanks a lot to everyone! I've finally got this thing figured out. I can now rest easy tonight haha!

[buzz lite beer]

To be quite honest, if your using a hybrid system your in the lap of the gods and getting a bow scale on your set up would exactly let you know what you have on your fingers for the likes of arrow selection. Many bow maufactures have deviated quite away from Earl Hoyts original geometry of the GM riser for what they believe to be improved performance, so too limb design. Border universal fitting limbs for example have developed in design so that the draw starts with a higher pull than previous designs for example the 1st 2" of draw you now have say 16lb on your fingers and with the earlier EP would be just 15lb.

[Allvyn]

Originally Posted by buzz lite beer

To be quite honest, if your using a hybrid system your in the lap of the gods and getting a bow scale on your set up would exactly let you know what you have on your fingers for the likes of arrow selection. Many bow maufactures have deviated quite away from Earl Hoyts original geometry of the GM riser for what they believe to be improved performance, so too limb design. Border universal fitting limbs for example have developed in design so that the draw starts with a higher pull than previous designs for example the 1st 2" of draw you now have say 16lb on your fingers and with the earlier EP would be just 15lb.

That was exactly what I feared. The Hoyt GM is outdated afterall but all I could afford at this point of time. I guess I'll go by feel and see how things work out.

By the way, what do you guys feel is the minimum draw weight required to reach 90 meters? Just curious.

[buzz lite beer]

The Hoyt GM is still easily capable of 1300+ FITA's in the right hands. To reach 90m is another can of worms, you read of people managing fine at 36lb with carbons. I can just about get 90m with navigators 41lb (have about 15mm clearance sight pin over arrow) and my do they stop in the air a long time, That I believe is due mainly to the distance from eye to anchor (I have short round face) plus never been convinced that my release was the best part of my form. Have a fellow at our club similar set up to yourself can get 90m but has to reverse his sight, so going off just those two cases would say 40lb+ with alloys to keep sight out in front of the bow though it may requiring moving in toward the bow some. I'm sure others will say they can get it with a lot less!

[BowSurfer]

Outdated or not it is still a good reliable riser at a pretty decent price. More modern risers may give marginally better perfromance, but the archer is the limiting factor and you have to be realistic about whether those differences are going to add points to your scores. Try before you buy and choose what feels good, and what you can afford, but I would personally still rather put the extra money into limbs than into the riser, unless I was rich enough to splash out loads of dough on both.
As to getting 90m (or 100yd) I have been able to get 100yds with 34# carbon limbs and a 29"draw, but only by moving the sight in close to the bow, but not having to go inside the riser. Even with 38# carbon foams I don't think that I am going to be able to get 100yds with the sight at full extension. Arrows are ACC 3-04.

[Rik]

Originally Posted by Allvyn

By the way, what do you guys feel is the minimum draw weight required to reach 90 meters? Just curious.

"Minimum" is another of those difficult questions. I have shot it with 32lb limbs (about 30lb on my fingers) and aluminium shafts... But it's sight reversal time in that case.
"Minimum practical" is a slightly different question. To get some sight extension out the front, you probably need lightish carbon arrows and mid-30s poundage. High 30s to low 40s would be better.