You are 100% correct. I had (read HAD) an Evolution 40, 60, and 100. All gave me lots of problems except the 40 at first. Later, though, it gave me the same problems, and all had to do with tuning and carb needle settings. They put those needle valve restrictors on the carbs, restricts the movement of the needle valve. According to them, all adjustments would remain in that range. Not so. Especially the low speed needle. All engines required substantial efforts to get them to run right, but never would run consistently, and that was all 'factory settings' that failed. Even after removing the restrictors, I had trouble getting them to run right.

I brought all three to the local hobby shop and put them on consignment. None have sold yet, and it's been about 6 months.

Want to buy one? Sell it real cheap...

DS.