Riser length vs draw weight?

[Pettit877]

Guys I am looking for a little input.  I am building bingham alternate riser 60" recurve.  I have changed the looks of the riser a bit and to achieve the shape I am looking for I needed to extend the riser 2" (1" on each end).  Will the increase in riser length effect my limb stack and increase my draw weight?

Eric

[Mike Mecredy]

Yes, providing the overall length of the bow stays the same.  It will add 6-10#.  

Is it a take down or a 1 piece?
 Either way if the over all length stays 60" and the working limb length is shortened by making the riser longer the weight will be increased.

[Pettit877]

Mike the bow is a 60" 1 piece.  Would you suggest I change my limb stack or increase the length of the bow?

Eric

[Mike Mecredy]

If you use the longer riser as you mentioned, you can make each limb an additional 1/2" and only add 3-6#.  And that 3-6# can be easily removed by narrowing the limbs sanding the fiberglass when you're through.  I'd have to know of an existing 60" bow of the same dimensions as what you're making, and it's draw weight and stack thickness, and the draw weight you're shooting for, in order to accurately tell you how much to reduce your stack thickness.

But a good guess, if I make a longer riser than I used before on a similar design,is; I'll take .010" off the total stack thickness, and it usually ends up being close to what I'm trying to go.