Hurrah, I can retire from giving instructions & parts lists for building Hybrid bulks at last
And very well priced too, only $90 which is about half the price of UE Ultralites ( 6 spider diffs with a plastic cup is plenty strong enough but most people, just a few guys around here who are nuts enough to require 8 spider diffs )....
I don't think the pinion is something they modified or make themselves, there are one or two Ofna models which have a pinion gear like that ( reduced in size from 8mm down to 5mm where it exits the diff case ). I've never been sure if those gears would work in the Hybrid bulks as some are apparently slightly smaller than others, but it seems like they do = all good news.
The ultimate Hybrids are the same as the standard hybrids but include diffs and the needed shim to make the diffs fit - the diffs are smaller than the earlier ofna/Hot Bodies diffs the Hybrids were originally intended for. The diff pinion is 8mm at the bearing and turned down to 5mm at the drive cup - similar to Mugen, AE, Losi, etc. :)
The ultimate Hybrids are the same as the standard hybrids but include diffs and the needed shim to make the diffs fit - the diffs are smaller than the earlier ofna/Hot Bodies diffs the Hybrids were originally intended for. The diff pinion is 8mm at the bearing and turned down to 5mm at the drive cup - similar to Mugen, AE, Losi, etc. :)
What diff will be included? If they are smaller that the ofna/HB, should they be weaker? Or they are better?
Absolutely, yes. They are a big improvement over the stock diffs. I prefer to use the 8 spider diffs with aluminum case myself. Have six of these diffs and one center diff.