sublunacy, I'm not an expert, neither of the 70 cc nor the 90 cc cylinders - but you ARE, as you've got your diploma and years of experience I'd say I don't even have a small piece of your knowledge on 2-stroke engines and I really appreciate that you want to share it here with us
Just wanted to show you that the pipe is really big. I'm not planning the 90 cc kit, I'll stay with the 70 cc. Just mesured the restrictor from the Tecnigas Silence Pro - its diameter is only 13 mm... But we both know what for restrictors are in that kind of exhausts Got my hand on the old stock pipe - it's 21 mm.
Depending on the shop, for the 70 cc cylinder they propose 17,5 up to 21 mm carbs.
I know I'm getting it from the back, but now we know that the exhaust won't block the engine The 70 cc cylinder will be able to evacuate the gases with no problem Now I have to figure out how to get the right amount of the air into the carb, and then, the mixture from the carb to the cylinder
As for the carb, I'll just buy the diameter I'll find with automatic choke and oil intake from the range 17,5 - 21 mm
Going further on from the carb, that's the only intake I've found, that would match the Dellorto 17,5 - 19 mm carbs (haven't check yet what's the intake diameter on the 21 mm carb). It's 2 pieces depending on the needed final diameter, I hope that putting both together will make approximately 90 degrees to get the carb in an appropriate position. Though I've seen a few days ago on an Italian website (could be Dellorto's) that it can be leant up to 40 degrees to the side. Got it in my bookmarks, I'll post it when I'll get to it later