No there not exhausting stock from the way it looks to me and the reason i say this is one simple factor that applies primarily to the Half breed engine and that is that the ZAE50 rod is a completely different rod than any of the other in shape and design, the only thing it has in common with the other short rods is just that... it is the same length but if you look is is a different rod and the only engines that use the ZAE50 rod are the half breed engines.
The 40mm stroke engine have NOT gone away, but evidently the 38mm engines must be a better deal for the vendors lately and thats why we're seeing so many of them coming over, when I had a legnthy phone conversation with Uane/thatsdax the other day I ask him about the 40mm stroke engines and he said he can still get them just the same as he did before, he just wanted to go with the current 38mm stroke engines this time around since they are well balanced also and some of his customers have requested them or like them due to the quicker spooling up into rpms that he said some of the racers had claimed.
The Half Breed/ Hybrid is just an added geometry that is not something new, I have one that I bought back in 2010, I didn't realize until recently what it was, but it is for sure a half Breed with the ZAE50 marked rod, only thing different about this old version is that it has narrow crank counters instead of the extra thick ones we're seeing with these Half Breed engines lately.
I honestly don't think anyone is thinning out inventories since the cranks and rods are completely different than are found in any of the 40mm stroke engines, these newer Hybrid engines are just a new mongrel type that takes from bot geometries to create what it actually is and that is a 38mm stroke PK80 40mm stroke variant, yes its a de-stroked 40mm engine plain and simple.
But who actually knows why they have go to this new geometry....?????
Biggest problem I see with the Half Breed is people having know way of knowing what they will get when they order from some vendors, at least in the past we kinda knew who had what, and we had two most common choices.
PK80 40mm stroke or GT5 type 38mm stroke, yes there have always been some variants even in these but now this Hybrid mongrel has added some unfamiliar flavor to the mix.
