A long overdue update on progress.
Buying a complete basket case bike as a dismantled heap of bits in cardboard boxes has proved to have some good points and some bad ones. The good stuff is that it's forced me to rebuild everything, and not be tempted to re-use something just because of the hassle of taking it apart to check it out. The really bad point is the small, but seemingly irreplaceable, parts that seem to be missing. Believe it or not I've spent more time trying to locate an RD50MX stand spring than almost any other part of the bike...........
Anyway, the frame has been bead blasted, primed and painted, the forks have been completely rebuilt (including new stanchions and seals) everything has been sprayed and I'm part way through assembling things. The Mars motor fits really neatly, better than I'd hoped. It's a tight fit in such a small frame, but I've ended up with the sprocket pretty much exactly where it was with the petrol engine. I've not needed to buy a new rear sprocket either, the combination of a 13 tooth front sprocket and the standard 48 tooth rear will be OK to be getting on with, I may switch to a bigger front sprocket if it has enough torque to pull the higher gear.
The batteries (64 Headway 10Ah LiFePO4 cells) are all going into the seat base, tail fairing and fuel tank area. It'll be a bit of work, but I'm making up a new seat/tail fairing/"tank" from epoxy glass. This will (hopefully) be lighter than the old shagged out seat, plus I intend to make the seat just a solo, saving more weight and giving me more battery space. It also means I can bin the rear footpegs and their brackets, saving another pound or two.
The instrument panel is nearly done. I discovered that a "Watts Up" display (when ripped from it's casing) "just" fits neatly into the old rev counter dial face. I need to add a remote current shunt (suitably uprated) but this looks pretty easy to do. As I'm running at 48V nominal, the Watts Up will do fine, plus it is a really cheap way of getting comprehensive metering. I've been playing with ways to keep it powered up all the time, so that it doesn't forget the power used (allowing it to be a proper "fuel gauge"). This seems to be nice and easy, as the Watts Up has an auxiliary power supply connection. I've hooked this up to four small NiMH cells, which are kept charged by a small (60mm x 60mm) solar panel. The Watts up only draws about 7mA, so this little solar panel provides plenty of charging capacity. The NiMH cells on their own will run the Watts Up for a week or two, even without a bit of charge from the sun.
With luck the bike will be back on it's wheels by the weekend, so I'll be able to wheel it outside and take some photo's of progress to date.
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