Did some stuff on the bike so time for an update.
Had a chain drop recently. My fault as I was in a rush to adjust chain tension with the chain roller. Didn't loctite the new bolt and it came off a couple of weeks later. Unfortunately the chain jammed after falling off and the end of the shaft got bent!
Hard to see in the image but it created more than enough wobble in the sprocket to make it unusable.
I have spares so all good. In the mean time I've made multiple welds over the bent part and hopefully it can be machined down to size nicely.
While I had everything apart I added a chain guide at the front and a spring loaded tensioner for the rear. It helps a lot to compensate for the slight eccentricity of the rear sprocket and its disc adapter. Hopefully it also helps with chain life as I suspect the extra vibration of the chain when the tension varies causes additional wear.
On the topic of chain wear I replaced the chain and sprockets for the first time. Its been a year and 7-8000km. I've also made the gearing even faster to 6.93 (97/14) from 8.25 (99/12). The motor still runs cool and I don't have to rely so much on the dodgy field weakening I implemented.
Bonus echidna I saw while out on a ride.