I’ve purchased an Overspeed warning indicator, originally from an aircraft instrument panel.
How will this be used on The Bride, and why? Well, it’s exactly what it sounds like.
The GX clone engine I’m using is designed to run at 3600 RPM. Losing the stock carb means losing the governor function as well. Un-governed, this mill will spin way faster than the existing spinny bits can cope with. While the con rod, valve springs, etc. could be beefed up, the cast flywheel is typically what goes bang most often (and most dangerously). A high-performance billet flywheel is the solution, but there aren’t any available with both charging magnets and starter gear teeth. So unless I want total-loss lights and starting, I’m stuck with a 3600-RPM-rated, cast aluminum flywheel.
So, how does rider know when they’re entering the danger zone? I’m going to hook the governor arm to a universal rear brake switch that’s wired to the aircraft warning light shown. Tune the spring tension so it comes on between 3800-4000 RPM, and – Voila – overspeed warning light.
With proper CVT tuning, the light should theoretically only come on once the gearing has maxed out.