Good day mate!!!!! Please do! I am so excited that you stumbled on this thread! We want to hear the whole story!
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I'll post some pics and words on my Bul later. For now though a few comments:
Cast high silicon pistons like the Mahles are great - they're strong, have a lower expansion rate than forged pistons and they wear very well. But on the other hand they are very heavy compared to a forged Wossner or Wiseco, and for an 80mm bore single running at 10k or so this is a big factor. For this reason I only run forged pistons - Wisecos in the air-cooled engine, Wossners in the water cooled one.
Forged pistons are tough, being made from a malleable, forgeable material. They can be made very thin which makes them so light and somewhat flexible. But they have downsides - they have a higher rate of expansion and they are very
very prone to seizure during the first couple of hours of use. They tend to shrink quite a lot initially, and continue to shrink throughout their life if they're used hard. It isn't wear, the skirts are literally knocked into shape during the run-in process. You need to keep an eye on the sizing if the engine is continually run hard either on the dyno or the track; you can easily end up with massive piston-to-wall clearance even though there's no visible wear. You'll notice both manufacturers now recommend clearances that would normally be considered quite tight for forged slugs, but they also stipulate lengthy break-in procedures. What really happens is that after the break-in procedures the clearance is "normalized."
The trick is in knocking them into shape without seizing. It isn't about heat cycles, it's more about subjecting it to enough rpms and load to get it to conform to the cylinder, very very briefly at first to avoid seizure and then getting progressively longer in duration. So you might give it full throttle for only a second or two at first, then give it a bit of time to cool before the next burst. Progressively increase the duration over an hour or so until you're running it for 10 seconds at a time at full throttle, at which time you could consider it good to go. Use a nice safe tune while you do this (the so-called Paris Hilton tune, rich and retarded) with plenty of oil before getting too serious about making power.
Of course you don't need to be so careful with cast pistons, but then they don't allow the revs that forged pistons do.
The other part of this story is oil. It's fashionable these days to run a synthetic, usually a straight ester. Unfortunately these oils are simply incapable of holding up in a high output two-stroke, especially an air cooled one. Esters are actually inferior to a good mineral oil in these applications. What you should be running is a castor-based oil; I run Shell M (20:1) but Elf HTX909 or Klotz Benol are also said to be acceptable. I semi-accidentally discovered castors advantages during dyno testing; not only does it make measurably more power it also makes measurably more compression pressure. I mentioned this to a kart-engine-designer aquaintance and he said, more or less, duh everybody knows that. He showed me some results of dyno tests he carried out on Aprilia engines that showed the same things as I found: castor made more power and compression pressure than the mineral oils tested, and at the bottom was the esters. Esters are fine in a streetbike or a moderately powered MX bike for example - and they do run wonderfully cleanly - but they just aren't up to a big-bore, hot running air cooled engine in a high state of tune. Castors run awfully dirty in anything that runs at part throttle for any length of time, but if the engine spends most of it's time at WOT and fully loaded it runs pretty cleanly.
I'll shut up before I wear out my welcome...
tacked the reluctor onto the back of the rotor shaft in three places. If this works we salvaged a worthless FEMSA electronic ignition rotor and updated it to use the Zeeltronic ignition. 
