Maniac57. I'm thinking these are PK-80 40mm stroke engines since all the sites I've seen that sell these as their only engines or kits sell the Type A pistons and not the GT5 Type B pistons.
About the longer bent clutch are, a few year ago I bought an engine only from BGF that is painted with a shiny gray paint and it has the longer bent arm, it came with a good looking crankshaft that is drilled and the transfer ports in the jug and case are the biggest I have ever seen and they are even shaped differently just a tad, it has silky smooth bearings in it also and like you said the one I have does have the larger front mounting area that fits perfectly on the Huffy and other larger cruiser frames, mine doesn't have 40mm wide intake stud spacing since as far as I know they hadn't made those yet back then and I'm thinking the Grube Super Rat was the first to have the 40mm intake stud spacing.
These ones that I'm seeing now don't say anything about having the larger front mounting saddle.
More than anything I'm curious about whether they have a good crank and rod in them, based on the shape of the transfer port areas hat extend out on the sides of the case I know they aren't the same engine as what I got from BGF back then but the rest of it looks the same basically right down to it being painted silver and all the hardware for the covers being flat blade screw driver type fasteners and Hex head bolts directly under where the jug meats the case.
An example of the engine I have in the pic below, look at the transfer port area on the side of the case and notice the shape the ports are larger and with mine the jug was made that that its ports matched the case, even the base gasket was shaped differently just a little and matched the larger ports.
And below is a completely different type engine that has the 40mm intake stud spacing which may be a GT5 TYpe, I'm not sure.
Oh well maybe the only way for me to find out for sure what they are is to just buy one and have a look see at it..LOL..!
I was just thinking that surely someone on here had bougt one of the from and ebay seller and might know a bit more about them as far as quality. they look to me to be a newer version of the old original PK-80/Power King Engine that was about the best that there was a few years back, but the the case isn't exactly the same because of how the transfer port is shaped on the case of this engine, Pirate Cycles used to sell some of what looked to be the original PK-80 but I think they were a lesser quality Re-pro of them.
Hmmmm, once I get past tax season and all I may have to just get one of these coming in the mail so I can find out what it is, might be a good candidate for a build to sell, I want to build a couple bikes to sell this spring and I'd like to find the best quality for the least so I don't have to charge to much for the bikes, these kits are actually cheaper than rose326 and I like the longer clutch arm and shorty intake that give more room and these come with the newer CDI that doesn't require a boot upgrade.
Thanks maniac57, looks like we both have an idea what these may be like in some ways but I still have a question or two that may not get answered until I get one in front of me and get the jug pulled off and the side covers so I can see some of the guts of the whole thing.
Map sits and scratches head in Central Texas this morning where it is 14F degrees... dang its cold for us down here today damp and just plain bone chilling....!