OK-one day later and I've just run it up several times on the now carefully balanced Cox 6x3-vibration is still present-so it may be a wee bit of a shaker. I have gained a few hundred rpm though-but whether this is due to the reduced vibration or simply a consequence or more running time is a moot point. 7000+ on a 6x3 would put it up there with the VA .4cc Mills and VA Kalper .32 for performance-so the little Tadpole is punching above its weight!
I haven't made up any of the specified fuel yet-will be interesting to see how that compares with my Model Technics D1000 mix. I'd expect the engine to perhaps sound happier-but produce less revs, on this mix (see previous post of scanned instruction sheet for the recommended fuel mix)
Here's some pics-on a rather cool Wellington morning..........