It all depends sometimes they loast a long time 20 gallons and sometimes they last 3-4 gallons.

If you fly on grass fields the plugs will go quicker from the dirt and crap that gets sucked up into the carb while running down the runway and just being started up in the grass areas.

here is a website that has details on setting the mixture and other ideas to help

http://www.probuild-uk.co.uk/factsheets/ys_engines.php


Troy newman
Team YS