Honda NC50: Restoration and rebuild

Once I'd got the bike running I tried to ride it- and literally got nowhere. The bike refused to take up the drive load. Originally I'd interpreted this as clutch slip, but when I realised that the motor wasnt speeding up, I attributed the problem to a lack of power. Lack of power can come from a variety of causes- and most of them I seemed to have- potentially at least. Firstly lack of compression- my bike is pushing 70-80 psi and should be closer to 120psi. Luckily I did have the rebored barrel intended for the orange bike so I fitted that with its new piston. This pushed compression to 120psi cold- has this cured the problem? Will check later because.... The second likely cause of low power is a blocked exhaust- 2-strokes tend to gum up with carbon from unburnt oil in use. I don't know if mine is blocked or not- it doesn't seem so but unlike other bikes where the echaust comes apart for cleaning, this is a sealed unit and cant be checked inside. Accordingly I decided...

I hadnt meant to clean and sort out the tank since its my intention to sell this bike as a project... albeit a running one using a temporary fuel supply. However, forced to wait for parts, I needed something to do anyway. Removing the tank I started by removing the saddle... it tips forward on a hinge plate revealing 2 flange nuts beneath. The nuts come off showing the washers and rubber mountings beneath.  The hinge plate then lifts off with the mountings leaving the studs. I reattached the flange nuts for safe keeping. The tank is fixed at front and rear; the front of the tank is retained by a short m8 bolt each side.  Bolts removed The rear is held by 2 vertical studs accessed from below... their position is indicated here by my finger. The view beneath shows the nuts are screwed  onto long studs and need a deep 12mm socket to unscrew them. Tank then lifts off revealing ...