ORIGINAL: thegoodson

if i could offer one piece of advice regarding scale drives, it is this; in full scale operation, common failure of these drives has to do with heat. specifically, the top most helical gearmesh is not immersed in oil or water as is the lower unit of the drive. therefore, after extended periods of running, even and "normal" speeds and loads, this part of the drive grenades. Mercury came up with a simple fix, and that is to shower the top of the drive with water to prevent heat build-up on top. i'd imagine in the R/C world, these drives have a similar weak point. if the upper unit of the drive can stay cool, or oiled enough, longevity ought to go up.