There's a question at the end of all this.
I have been tinkering with my OS FL-70 four stroke. I previously had it in an Acrowot but was never happy with its running so swapped it for a Laser.
Today I checked the valve clearances and found that they seemed to be way out. The intake and exaust were .25 and .3mm respectively. Like most OS four strokes my understanding is they should both be set to .04mm and certainly no more than .1mm. So i've adjusted these both to .05mm.
I've now run the engine and it seems to be running nicely and I was getting 9000 rpm on a 13 x 7 prop (only one I had available). It is the lower end however that concerns me. The pick up from tickover is a bit delayed, stuttered and slightly smokey. If I pinch the fuel tube at tick over, after a slight delay it increases in revs and then stops.
There is a single air bleed screw on the FL-70 and my question is, with the above symptoms, should I screw the air bleed in or out? I can never remember.
Chris.