09-01-2013, 08:15 AM
Valve inspection intervals vary between manufacturers. Yamaha specifies 24000 miles on some older models (FZ 5 valvers). Do you think they use better materials and superior craftsmanship than Honda? I doubt it. My buddy raced an '86 FZ750 and totally hammered it all season w/o checking. When he finally took a look, all in spec. Suzuki TL1000 motors are used for flat tracking out of wrecked street bikes. They never bother to check valve clearances, never have a problem. Key to keeping valve clearances is clean oil constantly being changed.
I had a CBX and it had 24 valves. It was so smooth and quiet at idle you could hear a valve that had too much clearance! Adjusting valves on that bike was like taking clothes off a beautiful sexy woman; very enjoyable!
One last tale: my old 1982 V45 Sabre had infamous oil-starved forked screw adjusters. I checked valves every 5000 miles for 25000 miles, always in spec, so I left them alone for the next 25000 miles because they weren't tapping. Few years later I checked them and there was ZERO clearance in all 16 valves and grooves in all 4 cams! But it still ran fine.
Summary? Modern Japanese engines come from factory perfect and go very far between valve adjusting as long as oil is clean.
I had a CBX and it had 24 valves. It was so smooth and quiet at idle you could hear a valve that had too much clearance! Adjusting valves on that bike was like taking clothes off a beautiful sexy woman; very enjoyable!
One last tale: my old 1982 V45 Sabre had infamous oil-starved forked screw adjusters. I checked valves every 5000 miles for 25000 miles, always in spec, so I left them alone for the next 25000 miles because they weren't tapping. Few years later I checked them and there was ZERO clearance in all 16 valves and grooves in all 4 cams! But it still ran fine.
Summary? Modern Japanese engines come from factory perfect and go very far between valve adjusting as long as oil is clean.