Whipped the heads off RichC's R90 last night to replace the exhaust valves. The bikes done less than 8k since having the seats, valves and guides done. The engine was noisy so we checked the valves the other day. These are two part valves but there's no identification on them so as yet we don't know who made them. We had to hacksaw the head of the valve off to get the valves out.