aermacchi

with a top-end gasket set winging it's way to us in the post, i set to and dropped the valves out of the aermacchi head, after all, they've been stuck in the same position for the past 30 year's or more, i measured the valve springs and they were well within tolerance, the inlet valve was perfect, but the exhaust valve and exhaust port were very sooty, sweary mick confirmed that it had been running very rich and not running very well all those years ago when he managed three laps of donington park before calling it a day and consigning the 'macchi to three decades under a blanket in the secret 'shed two', i lapped the valves in and span them up on the lathe to give them a good clean, finishing them with solvol to a high finish as recommended in the tuning manual, the ports in the head are a real work of art, once i removed the sooty deposit with some fine scotchbrite and a quick rub with white spirit the workmanship was revealed in all it's glory, the exhaust port had been polished within an inch of it's life, whilst the inlet port is cleaned up to remove the casting marks, but not polished and left slightly rough, added a few drops of clean 'r' to the valve stems and re-assembled the valves in the head after carefully cleaning any residue grinding paste from the valve seats with thinner's, once the valves were back in i dropped a little thinners into the ports to see if the valves were seating correctly, not a trace of fluid, job's a good 'un.....