Fozz, i think you might be blaming the baker for something the milkman did.
High revs and no rev control usualy means there is an air leak somewhere. O-ring under the pull start on a power torque. Or the inlet O-ring on the manifold, or the one on the other end the carb seats on. Split broken or melted vacuum line to the decomp. Stuffed decomp (to check swap it out for an old spark plug) Hole rubbed through carb body under fuel tank, ditto with the rear cover. Of the diaphragm i nthe carb is not seated right.
And last of all, the bottom crank seal (bearing) is shagged.
If they can suck air anywhere, they run lean and rev to the moon.
I only throw out the steel bit if the carbs not working right. Generally thats if ive put one together from bits. 90% of them i just strip the carb, clean it all up and put it back together and its fine.
Most important thing to check is that the throttle cable gets you the full range of movement. On some of the cables the plastic bit up in the air cleaner can be screwed up and down the outer adjusting the length so you can get full throttle. If this is wrong you cant adjust it up in the air cleaner to get full song.
Bob.
