So I recently purchased an unflown Ziroli 100" dauntless with a Zenoah GT80 installed. The engine is brand new.

I got the engine running but it was poor performance. The BEST I could acheive was 4400rpm with a Solo 20x10 3 bladed prop which by EVERYTHING I have read is actually on the very low end of prop sizes.

Further to that, I had to open the high speed needle 3 turns to get it to run at all. A far cry from the 1 1/4 I read on RCU and in the instructions.

So, I found a fuel filter that was to small, removed that, pulled the carb and cleaned it (it was spotless anyway) gapped and cleaned the plugs (which were new), checked the air gap for the mag (set to .014" as per manual), etc. The engine would not even fire at this point. I pulled the plugs, grounded them and spun the engine over with an electric starter and there was spark although IMO it seemed weak. We couldn't get the engine to even sputter.

So I go through everything again, attempt again to start the engine, this time there is zero spark, not even a hint of one. We checked all wiring, even bypassed the kill switch thinking it was a faulty kill switch. Wanted to try reducing the air gap but the damn bolts that hold the magneto on are completely seized, heat wouldn't budge them. At .014" though apparently that is correct, I don't know.

Gas is new gas, good quality 2 stroke oil mixed 32:1. Now I have a Mejzlik 24x10 prop on there (which is the prop to use from what I have read on RCU)

I'm at a loss. Further to that, Horizon has put me out on this engine. I sent them an email as they always have ridiculous wait times on the phone, and after 2 weeks have not gotten a response. I tried calling and using their call back number which they did call back but the guy I spoke to clearly had zero idea about anything. I told him all the things I have done and checked and he proceeded to ask if I had tried everything I already said I had done. I then asked him if I just send the engine in will Horizon install an electronic ignition on the engine, of course I would pay for it. He darted around that same question 3 times never answering if they would install it. Only saying "You'll have to send it in" and "Labor rate is $40 per hour billed in 15 minute increments". I asked 3 times about installing an electronic ignition (after all, they sell the damn things) and never received an answer.

Now I have also read that the stock mufflers are fairly restrictive and the builder added extensions to the exhaust to exit in scale location BUT, the extensions are a large diameter that while I could see SOME restriction, would not be causing a nearly 3000rpm loss nor should I think in any way that there should be any effect on ignition from that.

I have checked to ensure that neither piston has slipped on the crank (it was suggested to me to check to ensure both pistons were at TDC and BDC at the same time), I have checked compression on both cylinders, the carb has been cleaned, all wiring is good, it just boggles my mind that outside of a complete ignition failure, BOTH coils or plugs would fail at the same time.

I'm at a loss and particularly bummed out about this as it is a new engine, unfortunately it is past warranty on time. I keep hearing how reliable and good the GT80 is, but as of now, I'm not impressed at all.

Any advice? I'm willing to buy an electronic ignition and put it on myself, but I want to make sure I'm not missing something simple but difficult to track down before I spend anymore money.

Thanks in advance.
Jeremy