The statements of shindiawa and stihl co-development of the 4-mix/hybrid 4 was a stop gap because of being behind on 2 stokes I don’t exactly buy. They did this design very purposefully to save on over emissions from the lines to continue to sell the large pro level 2 cycles, if this was to be temporary they wouldn’t continue to use/develop them for the last 25 years. They were designed to be an efficient, quieter 4 cycle that could run at any angle and be smaller and lighter because of no oil sump. I’m betting this new echo revival of the hybrid 4 will just continue down the line and is to save on emissions also so they can continue the non stratto saws. Personally while more complex a 4-mix is smooth and has good torque plus was never designed or was I intended to make it into an actual chainsaw. Like it or not the 4-mix and hybrid 4 aren’t going anywhere and they want clean not too thick of oil it seems. The ultra was developed for the 4-mix because the orange bottle was causing wrist pin bushing failures on the early design 4-mix and as much as anyone hates it works well for this purpose. If Stihl thought it was going to drive warranty pill costs up they wouldn’t double your warranty when buying it.
