As far as the weight question. There are so many weight numbers. Like fire wall forward installed weight or engine and drive weight so im going to assume that when you say"final weight" your asking the weight with everything on it istalled on the plane. Mine come out to about 160 lbs. Thats with carbs exhaust bottles radiator ready to fly. So if your familiar with the weights of the 912 it is about 15 lbs heavier.
257 degrees is a lot hotter than Ive ever seen on my oil. If I remember currectly it runs 10 to 20 degrees hotter than the coolant. I would check your plumbing to your oil cooler. The yamaha oil cooler seems to do a pretty good job. No flight reports on the new Apex gearbox yet. I have switched gear manufactures and I awaiting another set of gears to test the clutch. The first set that the clutch was tested with showed no visual wear except on the sprag races. The hardness was no where near what I specified. The new gear shop, hardening shop and grinding shop are locally and I can check up on and control quality standards a lot easier.
I couldnt answer that question. Maybe jim hensel knows this. But until someone really figures out the 2011-2017 wire harness I think I would use the 2006-2010. The wiring and accesories are completely different between these group of years. Part of why the hp increase maybe because of power valves in the exaust which I cant imagine us using. I dont think anyone has even started looking at the later model harness. The good news with redrive options is the cases are the same so if someone ever tackles it we should have a drive
The FF intalled weight of the RX1 with everthing on it is aprx. 165 lbs depending on radiator and header choices. The Apex should be about 8 lbs less. The 912 FF is about 150 lbs. The 914 is aprx.175lbs. These weights are aprx. And I would love to hear anyone chime in on their actuall measurements. As a reference bare engine weight of the RX1 is 118 lb. So add carbs, airbox, radiator, exaust, ecu,voltage reg., oil, coolant. Gearbox/adapter and misc. Plumbing.