Yes, you can adjust the draw weight on certain recurve bows

Compound bows are well known for their ability to have the draw weight adjusted. Most have a 10-pound adjustment range, but there are some that can be adjusted from 5-70 pounds.

Did you know it’s possible to adjust the weight of some recurve bows?

In an episode of “Behind the Riser,” filmed by Shrewd Archery, which follows U.S. Olympian Brady Ellison during the 2018 Lancaster Archery Classic, Ellison talks about “taking three turns out of” his Hoyt recurve bow after the first day of competition. That action changed the draw weight from 52 pounds to 47 pounds. (Ellison went on the win his second consecutive title at the Classic in the Men’s Recurve Division.)

Brady Ellison

So yes, you can change the draw weight of certain recurve bows. The only bows this will work on, however, are those Olympic recurve and Traditional recurve bows that have ILF limbs and fittings.

ILF stands for “International Limb Fitting,” which is a universal limb attachment system that allows ILF limbs and risers from various manufacturers to be mixed and matched. Several Hoyt recurve bows employ a modified ILF connection system that uses the same hardware as ILF bows, but the hardware spacing is distinctly different than ILF. This unique limb connection system is the Hoyt Formula system. Formula bows adjust in exactly the same manner as ILF bows.

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ILF limb being inserted into ILF riser.

An ILF or Hoyt Formula riser will have dovetail pockets to capture the dovetail bushings on the limbs. And they’ll also have limb bolts. The limb bolts on these risers are adjustable. Turning the limb bolts clockwise lowers the bolts closer to the riser and increases draw weight. Adjusting counterclockwise raises the bolts and decreases draw weight. Also, nearly all risers with adjustable limb bolts use some type of locking screw to keep a limb bolt in place after adjustments have been made. It is very important to unlock these screws before adjusting limb bolts, and then lock them again when adjustments are complete.

According to John Wert, who heads the TradTech division of Lancaster Archery Supply, which produces ILF and non-ILF recurve risers and limbs, the bolts on ILF recurve bows have a recommended best working range. Starting at a maximum height of 20mm (13/16 of an inch) for lowest draw weight and adjusting in to a minimum height of 15mm (5/8 of an inch), for the highest draw weight.  Those distances are measured from the underside of the limb bolt to the surface of the limb pocket beneath it.

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“This is the best range for the entire sphere of ILF bows,” Wert said. “You can take some in or out farther, but then you are in a gray area that can lead to problems. If you know what to look for, you can adjust to as low as 12 mm and as high as 25 mm on some limb and riser combinations.”

The chief problem with turning in a limb bolt shorter than 15mm is the leading  edge of the limb bolt cap can start to dig into the limb surface. Back the limb bolt out more than 20mm, and the dovetail limb bushing can bind in the riser hardware– or even worse, the limb could fly out from under the bolt altogether.

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Left photo shows a limb sitting under a bolt set at 15mm, while the other is set at 20mm.

The number of turns an archer can put in or take out of a limb within that 15-20mm frame varies, according to Wert. Some screw patterns on the limb bolts are more aggressive than others, which would affect the total turns.

It’s up to each archer to figure out how many turns the limb bolt can withstand to stay within that 15-20mm gap. Likewise, the amount of weight that can be added or subtracted varies from bow to bow. It’s up to the archer to figure that out, so he or she knows how many turns are possible, and how much weight each turn gives up or puts back on. But generally, a set of limbs has an adjustment range of 8-10% of the limb’s draw weight.

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Turning a limb bolt with a hex wrench.

During the Lancaster Archery Classic, Ellison was able to reduce his draw weight by about 5 pounds by taking three turns out of his Hoyt limb bolts.

It’s important to note that equal turns must be put into/ taken out of the top and bottom limbs in order to maintain the tiller. Unequal turns will affect a bow’s tiller measurements, which can affect the bow’s tune and the way the bow sits in your hand.

Bow manufacturers vary on how they determine limb weights. Some, like TradTech archery, stamp their limbs with the low end of their weight range. So a TradTech limb rated at 50 pounds would draw at a minimum of 50 pounds at 28 inches with the limb bolts backed out to 20 mm. The weight would increase from there as the bolts are turned in and the limbs would reach a maximum weight of approximately 54 pounds.

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Other companies, like Hoyt, use the middle of the range for their limb ratings, and some rate their limbs at the top end of the adjustment range.

So all of this begs the question, “Why would I change the draw weight on my recurve?”

In the Shrewd video, Brady said he was having trouble holding his bow still at the higher draw weight. So he lowered it to gain more control. Other archers might find more control by increasing the draw weight.

Another reason to adjust draw weight might be to get an arrow to tune better. If the tune is close at a set draw weight, changing the weight just a little could be all that’s needed to get perfect flight.

How to know if your bow’s draw weight is too heavy

Are you drawing too much weight?

Getting a bow with the right draw weight is an individual endeavor. Everybody’s different. There is no prize awarded to the archer who draws the heaviest weight.

The most obvious impact of having a bow with too much draw weight is that you can’t draw it at all. If you can’t get the string back, you can’t shoot the bow. That’s an easy one.

But even if you can draw the bow, that doesn’t mean the weight isn’t still too heavy. If it is, accuracy is sure to suffer. It really doesn’t matter how fast your arrow is flying, or how much momentum it carries, if you can’t put it where you want it.

Compound bow archers seem to be most apt to try drawing too much weight. They know if they can just get the string over the let-off hump, they’ll hold much less weight at full draw. But that over-exertion at the front end can weaken you at full draw – especially if you’re in a tournament situation, where you might have to draw and shoot 30-60 times, or if you’re hunting and end up having to hold full draw for an extended period while waiting for a good shot opportunity.

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Having to point the bow toward the sky is a sign of drawing too much weight.

If you have to point the bow up at the sky, or pull down toward your waist in order to get the string back on a compound bow, you’re pulling too much weight. If you have to collapse your bow arm shoulder inward to get extra leverage, then the weight is too high. If you find yourself shaking at full draw, it’s too much. If you can’t get through a simple practice session without feeling fatigued, then you’re pulling too much. You should be able to hold a compound bow directly in front of your torso, and draw the string without struggling.

If it’s possible, reduce the weight by turning the limb bolts counter clockwise. Whatever you do to one bolt, do exactly the same thing to the other. If your bow already is set at the lowest draw weight possible, then you might have to get another bow with a lower draw weight range. Or, you might be able to get replacement limbs for your bow that are rated for a lower weight range.

Recurve and longbow archers almost invariably will draw much less weight than they would if they shot a compound bow. Compound bow archers who switch must understand there’s no way they will draw and hold with their fingers the same weight they draw and hold with a release using a compound bow.

When you draw a 70-pound compound bow with 75 percent let-off, you’re only holding about 18 pounds at full draw. When you draw a 50-pound recurve – assuming you have a 28-inch draw length – you’re holding 50 pounds at full draw.

The most obvious sign that a recurve archer is drawing too much weight is he or she will shake at full draw. If you can’t hold the string back for even a few seconds without shaking, you’re pulling too much weight.

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This archer is comfortably holding her bow at full draw. The weight is not too much for her.

Check your accuracy with bows of varying draw weights. If you’re pretty consistent at 40 pounds, but then notice erratic arrow groups at 50 pounds, then 50 pounds is probably too much weight.

World renowned traditional Archer G. Fred Asbell recommends a test for determining if an archer is over-bowed.  While bending at the waist and aiming at the ground, an archer draws the bow with the back of the bow hand just below the inside of the knee. If an archer cannot do this easily, he or she is likely not strong enough to shoot that draw weight.

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Archers shooting takedown recurve bows can usually get lighter limbs to drop some draw weight. Those who shoot one-piece recurves or longbows are going to have to switch bows.

Just because you might not be strong enough for a certain draw weight right now doesn’t mean you can’t ever shoot that weight. The more you shoot, the stronger you’ll get. Couple your practice sessions at lower draw weights with strength-training workouts aimed at your core and upper body muscles.

As you get stronger, increase your draw weight incrementally. If you notice any of the problems we’ve already discussed, back off. Over time, you should be able to reach your goal weight, and be able to handle that weight with ease.

Now you might say to yourself, “Well, I’ll just keep shooting this heavy draw weight, and eventually, I’ll get used to it.”

That’s a bad move. The whole time you are struggling with that heavy weight, you’re tossing good shooting form out the window. A great deal of solid archery shooting form relies on muscle memory – training your muscles to know how to perform correctly during the act of shooting a bow. If you train your muscles to do the wrong thing, then that muscle memory is worthless.

When it comes to draw weight, don’t go for the gusto. I’d rather be able to drive tacks with slower arrows, then have them fly screaming fast, but rarely hit those tacks.