These CB400s with their two-valve inlet and one-exhaust heads were the fastest 400cc four-stroke machines of their time. They have now become recognized as the great middleweight classics they always should have been.
Their restoration however was fraught with difficulties due to the scarcity of available spare parts, but now at least this area of ​​the muffler system can be renewed with this newly produced system.

Please note that these downpipes are single wall and may discolor to a bluish color during the first few runs. This is quite normal.
Discoloration will be less when the carburetors are adjusted properly.