Hi.

If the engine parametres are ok, it's not necessary (and often not even possible) to use tacho. Just start from rich setting and turn needle in untill rpm starts oscillating just before solid 2-stroke. Normally the good launch rpm is the oscillating mode or just a little leaner, depending of tank position.
When you're happy with run, you can fine-tune flying speed by tweaking the prop.

Lauri

Hi Bill.

 I'd rather use Yuriys props, they are better than Rainbow's.
 You can tweak them using heat & pitch gauge, just like carbon props.
 Well, allmost. The important thing is, that to get good results, you must get the section of blade heat completely hot. Not just the surface. So you must heat patiently and carefully to avoid burning the surface. Wood gets soft at about 100 degrees (Celsius).
 The Yatsenko props I tweak only from the root. This is usually enough, and it also makes a nice wash-out towards tip (if I reduce the pitch). If there is need to tweak from closer to the tip, be carefull not to alter the airfoil. then just hold something flat (like a 1/4" sq. piece of balsa) against the blade bottom when you tweak.
 To tweak, I pre-set the gauge to desired pitch and clamp the indicator so that it stays in place. Then I heat the root of prop, and then quickly put it to the correct groove in gauge and twist to correct pitch. It's good to tweak a little too much first, and then to return to correct angle. Only that way they stay like that.
 People are usually very sceptical about this.
 Yuriy's props differ from Zinger, Rev-Up and other similar crap because his props has pretty and well thought airfoils. So it's not very wise to alter their pitch by removing material.
 L