Here is a video of me testing ignition sources and fuel delivery: https://youtu.be/wLrP70CLfi8 And below are tools that make life a zillion times better when doing carb work. The long hex wrench reaches way in to get to the inner airbox screws and the upgraded carb float bowl screws, the jets are available in many sizes and come in pairs... so only order 2:
Gates has a good selection of tees and reducers as well. My system simply has a tee right before the hot goes in the radiator, and another right after the cold comes out. Run those up to the core. Pretty simple. I have a SOV by the core but I don't think you'd necessarily need it.
Maybe consider a heater core type cabin heat? A lot safer and also gives you additional cooling capacity if you ever needed it. Couple extra pounds of course. (Firewall is on left, white tube going up to windshield, fans ziptied on top that blow down through it)
As far as clamps, I am sold on oetiker clamps. Nothing squeezes as tight, is as 100% secure, grips all the way around the hose (zipties and worm gear clamps always have a slack spot under the tab) Just gotta be careful not to put the oetiker in a location where you cant remove them easily (to remove I cut the compression tab with a dremel cutoff disk)
These puppies need to breath right or you will miss out on a ton of HP that they are capable of. Header design is well beyond my knowledge and experience so I went with advice from others, but here's a quote from a performance shop that sheds basic light on the topic: "Header primary tube tuning has two basic parameters: airflow requirement and exhaust pulse tuning. Tubing diameter is dictated by flow requirement, which in itself is determined by engine displacement and rpm... Header primary length has to do with timing the exhaust pulses so that the exhaust from one primary helps to suck the gases from an adjacent cylinder."
It gets real deep. Bore, stroke, valve duration, and other factors change design parameters. But in a basic sense if the header isn't done right it will have the effect of putting a potato in your tailpipe!
Nice write up. And nice that the hardy disk fails in a propeller turning mode like that. Additionally, for anyone that missed it, in the Yamaha group we saw two Cbox's with damaged bearings because the pinion shaft bolt (bolt #19 in the first diagram above) came loose. The Rotax service center recommend (whenever servicing the gearbox) to make sure to clean up and dry the threads (male and female) - use plenty of red loctite - get it torqued right (212 in-lbs) - and let the loctite cure before refilling the oil. Also a pinion shaft axial clearance check is a good idea.
FUEL SYSTEM: Hooking up my fuel feed today. I went with a Facet 40288 (2 - 4.5 psi) with a built in check valve that allows free flow through it but no backflow. Past the Facet pump I put one of the Yamaha vacuum pulse pumps in a parallel loop as a backup in case the elect pump fails. (Note that the pulse pump does not allow flow through it in either direction, so it needs a bypass line around it in case it fails). In the pic below I forgot to label a check valve I'll be putting in the bypass line between the facet and the fuel pressure guage fitting. It will go in the location of the green circle in the pic below. Without it, when the pulse pump is running standalone it would "feed itself" in a loop (instead of the carbs) and will not draw from the tank. Of course all this will be firesleeved / heat shielded as well due to proximity to exhaust. I will test to confirm how this all works and update this post.