So the update as promised!
The goal for last weekend was to complete the install of the speedo sensor for the Vapor, pump the tyres up, then go for another hit to verify top speed.
But firstly, - the Vapor. I was originally going to buy the most basic model which measures just the cylinder head temperature. But given the 70cc upgrade was always in the works, I thought it might be useful to also monitor RPM’s and have a Speedo once the new engine was in. Setting up the RPM and temp gauge was easy enough, but I had to figure a way to make a bracket to mount the speedo sensor, which I have placed on the rear wheel. Apologies for grainy photos in my dimly lit shed, but you get the idea. That being done, I calibrated it by sitting my weight on the bike, rolling forward 4 full rotations, and divided by 4 to get the tyre circumference, which was programmed into the Vapor.
As per the photo in my last post, it read a top speed of 48.4km/h, or 30.07mph, which is exactly what I expected with inflated tyres. For whatever reason, the GPS app I was using on my phone registered 58km/h (36mph), which from this point I am going to disregard as I believe I have the calibration of the Vapor dialled in to within 1mm of the actual rolling circumference. As a side note, the max head temp was 405F.