08-04-2013, 01:55 AM
(08-03-2013, 09:39 AM)Yoyodyne_imp Wrote: Apparently the CB500's power plant is the first multi-cylinder engine that Honda has built outside of Japan (it's made in Thailand), so that may be why they're being extra conservative on the initial service requirement.
Curious, I had a look at some pictures of the 500's valve gear. It's similar to the CBR250's in that it's not a 'cam over bucket' arrangement. There are more pieces involved. The cam doesn't bear down on the valve, instead it pushes on a follower and the follower spreads out to 2 fingers to open 2 valves of a cylinder. Perhaps this 'extra' parts count along with the limits of manufacturing tolerances means that some 'early' wear in can occur and needs to be checked. Significant wearing sure happened on my 250, whereas I read of one case in which someone checked theirs at 600 miles and found that all of them were in spec (lucky devil..).
While I could manage to get the head cover off and measure my valves, it was clear that I was not equipped to carry out the surgery required to change the shims (it's *really* tight in there, the frame gets in the way of everything)... paid the $200 for the dealer to set the valves (not a 600 mile service, *just* the valves)..