How to understand Reflex Deflex Bows

Understanding Reflex and Deflex risers

Thousands of years ago, man did not truly understand the technology and how it affected the bow. As a result, different styles of recurve bows were used in different cultures. By understanding the differences in their style of archery and hunting, you can see why some cultures chose different styles of bows.


Today we still toy around with different types of bows. However, when you are talking about recurves in the competition, you see manufacturers selling you on the idea of "more deflex" tuned striker bows. Understanding the purpose of what a more deflex bow does will help you gauge why all the hype is around today.


How well do you understand reflex deflex bows?

To make this simple for you to understand and not go into the science and technical aspects that most won't understand, this article is a base to help you to get to know the difference and why they are important.


Reflex bows are designed to have the limbs pivot point in front of the archer's hand or more easily to see in front of the grip pivot point. As you can see in the picture, this bow has a slight reflex design and puts the limb pivot points in front of the hand. (This is a deflex riser but with a more reflex design than average. You will understand better later on.) The red line is drawn from the limb pivot point to show you the relation between the riser ends and the distance from the grip. 


Deflex bows are designed in the opposite way. The limb pivot point is behind the pivot point of the grip. Take a look at the picture and compare it to the one above to clearly see the difference. By using the red arrows, you can see how the more deflex riser has more gap from the grip in comparison. You will notice this later on in the article as well. 


As for the definition of the two styles, this is as simple as it gets. Reflex and deflex refer to where the pivot point of the limb sits in relation to the pivot point of the grip. Simple right? You bet it is, at least until you start thinking about why the two designs and how they play a role in our shooting.


Reflex bows are much faster than a deflex bow design. Several factors come into play to make this happen. First, suppose you are up to speed on how brace height affects arrow speed; this will be easy to understand. The lower the brace height, brace height is the distance from the throat of the grip, the faster the speed. We know this because by lowering the brace height, you, in turn, weaken the arrow shaft spine, thus meaning more speed is introduced and therfore better draw weight.


The purpose of each design has had its place in traditional archery designs. However, it is now making its way back into the market.


If you have a short draw length and cannot get the speed you want, reflex design is more your speed. On the other hand, if you are looking for a more forgiving bow and speed is not a concern, then a deflex bow is what you want.


In an age where speed dictates what we buy, the idea behind a more reflex design bow has been a focus. Speed sells to the masses, but accuracy is what wins. With speed, you will undoubtedly sacrifice some accuracy. The trade-off is of personal preference in the end, but the result for some is pinpoint accuracy.


So how does each striker bows design make or break the archer?

If you are an incredibly accurate archer with little mistakes being made, then you can shoot a more reflex design bow. For the masses, however, a more deflex bow is better and more forgiving.


Most recurve and striker bows today are of deflex design. Does the question become how much deflex is built into the riser? Most entry-level good risers have quite a bit of deflex built into them. The reason is simple. The more deflex, the more forgiving the bow is and the more accurate.


By giving a new archer a bow that shoots more accurately, the more confidence, they have quicker. The quicker they get better, the quicker they buy a new riser. So why not make every riser with more deflex, to begin with? The reason is that while having a more deflex riser with more accuracy, the less deflex riser is faster and faster wins in the wind and at a distance. There is a trade-off, remember, and you can cross that fine line easily.


Win & Win makes mostly high deflex risers from the base range to the top end. Ask many archers why they love their Win & Win, and they will tell you that the bow seems to shoot better have less hand shock. On the other hand, Hoyt has used a much less deflex design in recent years on their high-end bows.


They have found a balance between speed and stability, and it shows. Recently Hoyt has brought back the RX design, which has more deflex than in previous models. Notice in the picture below how the old RX design had more deflex built-in versus the HPX, which was and has been a very successful bow.


Why more deflex now, then? Back to the beginning of what the modern riser design is mainly based on, the Hoyt GM TD2. Earl Hoyt used more deflex in his original design than anyone probably ever thought of without notice. The following decades gave way to very similar geometry with very slight differences. In more modern times, technology has introduced risers with less deflex, making for quicker bows.


Whether you are new to archery or an expert with decades of shooting skills, the more deflex designs offer more accuracy regardless of brand. Shoot a less deflex riser well, and the more deflex risers will help make you even more accurate. 

Don't feel alone if you don't understand how brace height affects the arrow. 


There are two types of brace height. No, not high and low.

The first type I call "Natural Brace Height." This is the bows natural brace height based on the geometry of the riser design. Is it reflex or deflex in design? As stated before, a reflex design will have a lower brace height, and a deflex design will be higher. Given the same limbs and length of string with the same number of twists, you would see this naturally happening. This is why I call it the Natural Brace Height. You can achieve the same brace height for each design by making the string longer or shorter when made or changing the number of twists.


The second type of brace height is what I call "Adjusted." By changing the string length as stated above, you can adjust the brace height for either design of the riser to be the same.


So why the fuss with two designs, reflex or deflex, if you can "adjust" the brace height from its natural location?

If the riser has a more deflex design, the natural brace height will be higher. Remember, the higher the brace height, the slower the arrow, but the more stable and forgiving it will be. A riser with less deflex with a natural brace height being lower will be faster and not as forgiving. You can change the brace height by adjusting it, but you are changing the natural nature of the bow.


Let's say that the less deflex riser naturally rests at 8.5" of brace height and the more deflex riser naturally rests at 9.0" brace height. As an example, without adjusting anything, you can see that the more deflex riser is already closer to a more forgiving setup without any adjustment. However, by adjusting the less deflex riser and bringing the brace height up to 9.0", we have to short the string via twists if possible. This increase in brace height will affect the arrow spine some and stiffen it. To go up to 9.25" of brace height, we will drastically change the arrow flight and tune, where the more deflex riser will be naturally closer to the 9.25" of brace height with only a few twists. This allows us to keep the spine much closer for tuning and still give even more forgiveness without being far from the natural design of the bow.


Forgiveness is a term used lightly, and nothing makes it truly more forgiving. But what it does refer to is that a more forgiving bow is purely a more stable and accurate one.


While a higher brace height is a tad slower, it is more stable. The idea is to introduce more deflex into a riser to stabilize the bow.


So what do you know now? You know that a reflex design is faster at the cost of accuracy because the bow naturally is not as stable. You know that a deflex design is slower at the cost of more accuracy because it is more stable.


Want to see the proof? Over the past year or so, you started to see some changes in what risers are being used. Take a look at some top archers, and you will notice that more and more Hoyt GMX risers are being used. The Hoyt GMX is an ILF riser with more deflex geometry built into it.


You will also start seeing a lot more Hoyt Prodigy RX risers being used, which also have more deflex built into them. Both risers use Earl Hoyts original geometry dating back to the TD2 over 30 years ago. Win & Win already use a more deflex design and have had their success stories as well, but keep in mind that they stuck with their geometry for the most part for all of these years.


The simple truth is that more deflex to equal a natural 9" brace height is still the way to achieve a more stable and accurate bow. Technology is moving forward only to find that old designs are more in tune than we ever imagined.

Hoyt Formula RX and Hoyt GMX (Old deflex geometry, just like the TD4)


So the next time you are shopping for a new riser or reflex deflex bow, you will now have one more thing to think about before pulling the trigger. It better be an accurate decision.