Wise choice going with the timing mod, it makes a huge difference to the running of the engine. The crankcase mod is one of choice, as it is quite a 'drastic' change, but I use a similar thing on my two engines, and they are working well. I would suggest a higher oil content for breaking in, nothing wrong with 20:1 with the mods as a break in, once you have done a few tanks, drop the oil to 30:1.
While breaking in, its usually the No.2 cyl (or No.3, or both the lower ones) that doesnt fire up with its friends, but since you have done the crankcase mod, it will be any one of them. In essence, the very rich fuel will cause the mix to not burn properly, but as you start leaning it up, the odd cylinder will start acting as per normal.
I found it quite useful to use the stock pipes while breaking in, as I could see WHICH cylinder wasnt firing properly and this was before the crankcase mod had been used to effect. As many people have done, I physically 'rotated' the engine between tanks so that all the cylinders got a chance to run lean and fire properly.
You seem to be going down the right road but it might be a good idea to up the oil a little while running in... make sure all the parts get some 'slippery stuff'. Pretty much EVERYONE who got these engines noticed that there was VERY LITTLE lube in the crankcase when new, and most have squirted some oil in there, as well as in all the rocker covers....get that valve train all slippery.
22x10 is a good sized prop, but depending on what plane you are putting it in, you may find something with more pitch is also comfortable maybe a 22x12, 21x12. Some prefer the power and less speed of a 23x8....depends on airframe and flying style required.
Sparky has it nailed...valves just set with the tool they give you, I use a 0.05 feeler guage and that allows a 0.1mm guage to be tight..closer the better, as long as they are not holding the valve open!
My thanks for the replies, I have now had five quite long flights on the engine, still using the 30/1 oil. Each start from cold it is the top cylinder that takes a while to join in but now that I'm expecting it, it doesn't seem so worrying. I take your point about using a little extra oil in these early flights so will up the oil content to 20/1 for the rest of this gallon. I have kept a check on the amount of oil in the rockers, Theres evidence of oil there, less in the top cylinder so I have kept adding a littleat every check. I have no idea whats in the crankcase. (The drain is closed off by MMM)The valve gap seem quite loose so the next step will be to reset those now that is bedded in a little.
P.S. I have a spare Saito Collector ring (its the branded Saito one) not the best sound, but it does a good job. If youre interested let me know, I would part with it for a lot less than what its available for..
Yes I would be interested in the collector exhaust. I'm in the UK though, your in Dubai? I've sent you a PM
regards to all,
Stu K