Guys,

Some great information - thanks for the help. My MVVS 91 is definitely ABC with no ring. It's un-run: in fact, listening to what's been said I've even resisted the temptation to turn it over compression. Anyway, Just Engines are sending me an in cowl silencer for my Edge 540 which should arrive tomorrow. Friday is half-day so I'll be out the back with that MVVS giving it some! Might be able to take the model out at the week-end if the rubbish English weather sorts itself out...

Out of interest, Just Engines send an instruction sheet out with their new motors. All the ABC engines I've had from them include the recommendation to start at 1/4 throttle and run a tank through very rich before moving on to two tanks at half throttle, very rich.

I shall be doing as you all suggest though and come back after the week-end with a report.

Cheers,

Mick.