# Difference between Formula RX and Formula HPX??



## IceArcher (Mar 6, 2012)

I've been wanting to upgrade my riser to a Hoyt Formula HPX, but I'm not quite sure what the difference is between the Formula RX and Formula HPX? (also, Formula Excel - that's similar too?)


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## limbwalker (Sep 26, 2003)

Formula Excel and Formula RX share similar geometry. Excel is the "budget" version of the RX.

HPX has the "new" Hoyt geometry, with less deflex in the riser, and is designed to be shot with a lower brace ht. 

Essentially, the HPX is the RX with the grip moved back toward the archer 1/2" or so. This allows archers with normal draw lengths to get a little more out of the limbs than normal. However, if your draw length is extra long (like mine) it may be counterproductive - causing the limbs to start stacking even sooner than on the more traditional RX geometry. 

No one riser or set of limbs is best for everyone. Bows tend to perform best right before the limbs start to stack. This offers the most performance but still a smooth draw through the clicker zone. 

So if you go with the HPX, you'll likely want a longer bow than you'd normally shoot. Say, a 70" bow instead of a 68" bow for a 30" draw, and so forth. This would ensure that the more agressive geometry doesn't cause the limbs to start stacking at your clicker zone. 

If you stay with the more conventional geometry, you could shoot a shorter bow and still get a smooth draw through the clicker.

These are generalizations, of course. And not all limbs are designed the same, so for example, the F7 limbs may draw smoother than the F3's, and allow you to stick with the length bow you've been using. It's really hard to know without setting one up and drawing it.

Folks are reporting 5-7 fps. increases in arrow speed with the more agressive HPX riser combined with the F7 limbs. Not sure how much of that is the riser and how much is the limbs, but in my experience, the RX with F3 limbs were a good 5 fps. slower than all my other bows already, so this "increase" doesn't really impress me that much from a pure speed point of view. IMO it just gets the Hoyt bows "up to speed" with the Samick, W&W and SKY gear that's already out there shooting. And if speed is what you need, they are all behind the Border limbs. But not everyone needs so much speed. It's an individual thing you have to decide.

John


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## IceArcher (Mar 6, 2012)

hmm, alright, I might end up with a Formula RX then, thanks for your help!


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