> >>>> >>   Hi Jerry

 >>>> >>  If you want to build a cog belt redrive I can make custom pulleys.
 >>>> >>  Check out my web site and you can see some of the pulleys that
 >>>>I have made.
 >>>> >>
 >>>> >>  Ken Welter
 >>>> >>  http://homepage.mac.com/rotarycoot/

 >>>> Ken, do you have prices on the different sizes
 >>>> Namely a 3.11 ratio, and a  2.95.
 >>>> Thanks
 >>>> Royce

 >>   The 2.95 and the 3.11 use a 118 tooth upper pulley made from
 >>aluminum and the price on it is $900
 >>
 How wide are these pulleys

 >>   The 3.11 uses a 38 tooth lower and the 2,95 uses a 40 tooth and
 >>they are made from 1045 steel and the cost is $400 for the lower ones.
 >>
 What is the reason you use steel for the lower pulleys, and not aluminum?

 >>  For a lower horse power engine
 >>
 How much power with this redrive handle?

 >>the pulleys could be much smaller in
 >>both diameter and width cutting the cost way down as the 60 pound
 >>
 You start with a 60 lb block of aluminum? Wow.

 >>chunk of aluminum that I make that 10 pound upper pulley from costs
 >>me $350 and you wouldn't believe what 50 pounds of shavings looks
 >>like.
 >>
 >>   Ken Welter

 Goodness Ken, isn't there a better, more efficient way of doing that?
 We have looked at your web site, looks like you do a fine job on the
 redrive.
 How do you put the correct tension on the belt, an idler, or adjustable
 upper pulley?

 > Royce

   There may be a more efficient way but this is the only way of doing
it that I will hang my rosy red on.
   The reason for steel on the lower is I don't trust aluminum there
as I have seen problems with other redrive's having structural and
wear problems and for what little weight there is to save I would
rather stick with steel.
  As for belt tensioning if you look close at the upper bearing
carrier it is adjustable, the belt runs with slack in it and the
centrifugal force throws the slack outward and tensions the belt
tight to the pulley. This bulge also acts as a torsional damper as
the engine pulses get absorbed trying to straiten the belt.
  As for power I am running about 300 hp on takeoff from the water
when using the nitrous. I may have a line on a 20B and if I get it I
will go to a 120 MM wide belt as I don't believe the 85 MM will
handle it.
  Ken Welter

 
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