I've posted the inane rantings of motorcycle noob here before. Safe to say it didn't got down t0o well so I'll keep this short and sweet. This is my bike. It's my first. Yes that's an L plate on the back . I got it in a much worse state and it ran but not very well. It didn't have the shiny decals and new paint either. It was a POS but I could see some potential and I like the idea of saving this thing from the junkyard. I also like the way it rides when it doesn't overheat. This is my problem, it goes great until 30 minutes in, gets jerky, loses power and wants to seize. Things I, or occasionally my mechanic, have done to it thus far: - New (old) fuel tank cap, fuel tap and hoses. The original tank cap had a venting issue that stopped flow and the tap leaked. All good now. - Carby cleaned and adjusted. Runs perfectly well until it seems to get too hot... Plug shows a darkish tan. Maybe a bit rich. - Timing checked. Spot on. - New battery and rectifier. Charging just fine. - Oil pump works. It is using oil and within the threshold marked on the pump itself. - New top end including rings, piston, bearings and gaskets. Re-bored by a reputable firm I am 500ks in. It's been tumultuous. - Today I de-coked the exhaust with caustic soda and got a heap of shit out of it using a coat hanger. Some jerk in the past decided to spot-weld the baffle in place so I did the best I could. After this it went like a bloody rocket. With the exhaust de-coke I thought I had it solved. It was accelerating much better at lower revs and spinning freely right up there. It sounded better too. It was 33C today and I was riding for about 30 minutes and was sure this had helped the overheating. Until, around the corner from my house it starts getting jerky and wants to stop. I hit the kill switch. What else do I do? Does the bike need an exorcist? The bike starts first kick almost every time. Idles perfectly well forever. Rides really great, today it rode the best it ever has, I smiled when I looked back and saw that perfect little line of two stroke pollution flying out the back :) Any ideas are most welcome.