Hi Dave,
I tried running one of mine on the bench with the R/C carb locked open, and found that just breathing too hard on the needle caused big changes in rpm! Pretty sure that was either sloppy threads on the needle, and/or poor fit of the carb barrel.
As Dan said, the conversions are pretty simple, so I would recommend doing that.
I've used both the sleeve J-B welded into the existing case opening, and the stock Cox Tee Dee .049 venturi screwed into that, or better yet the excellent conversion kits made by a fellow forum member (who unfortunately doesn't make them any longer).
If I had to use the existing carb I'd run it in the air to find the best carb opening, as they usually have better fuel draw with the carb closed a little from wide open! Of course wide open may work OK in the air, where the engine unwinds a little after launch. A good indication that the carb is open too far is the engine slowing and/or dying immediately after launch, but other things can also cause the same symptoms.
One problem some flyers have reported was caused by using too small fuel line on hi-performance engines like the Wasps, etc. The fuel nipples on some engines are misleading, as the nipples are smaller, and easily except too small tubing. Check for that, and use the next size fuel tubing with fuel line clamps, or twisted copper wire to keep the ends snug on the nipples.
Bill
Topic: Wasp .061 and BMJR TEOSAWKI (Read 724 times)
