Well the 26cc gas engines are different from each other. The older design side carb, side exhaust RCG/RCGF 26cc engine weighs like 1200 grams all up with everything including the muffler (1050 grams without the CDI unit). The Turnigy 26cc engine is a rear carb, side exhaust engine and weights a little less than that of course. Then there is the MVVS 26cc gas engine and it weighs around 1,400 grams all up with everything, but it varies as to the muffler or exhaust system used. I think that MARK or MOKI has a 1.40 that weights about the same as the MVVS gas engine too.

Now then a DLE 30cc gas engine doesn't really add more weight in comparison to these 26cc gas engines I show above. One has to watch out on the advertisement hype as they tend to leave the muffler and CDI unit out of the weight information

But then I sort of like the 26cc gas engines though. I think that they would work fine depending on the circumstances. If you needed more weight up front for the CG on a plane then the heavier engines are a big plus in that respect. But if you don't have a 26cc engine but you have a 30cc engine, I do not see anything wrong with using it either. So it depends.

So technically there isn't any reason for DLE to make a 26cc engine as they have that size range bracketed with the 20cc and 30cc engine sizes. Also the 20cc gas engines are quite a bit more powerful than they were years ago too, so even a 20cc may be adequate in some cases.