A lot has been said about the failure mode of first-gen Honda V4 camshafts. Many have devoted web space to the subject, postulating this theory or that. Unfortunately, the emphasis on these sites is invariably on oiling. But it just isn't true. Despite this, special oiling mod kits popped up all over. However, these kits exist solely due to a misunderstanding. Someone probably observed that Honda's race team was using handmade external oil lines on its Interceptor-based racebikes. The assumption was apparently then made that this was to counter cam wear (though the race bikes didn't use anything resembling stock cams) and before long, everyone "knew" why V4 cams failed. But there really is no connection, not on the race bikes and not on consumer's bikes. The race bikes used braided oil lines simply because the stock soldered steel oil lines cracked when the machines were used hard. It was common, according to American Honda, for whom I worked in the 80s. It also happened on a bike I raced.

Ask a career mechanic about lubrication-caused cam wear. Pro mechanics know what cam failure looks like. And one look at a V4 cam and it's obvious the wear has nothing to do with lubrication. The powersports industry has always offered many opportunities to encounter engines that fail due to lubrication. In addition, outside our industry, historically, camshaft wear in overhead cam automotive engines due to lubrication issues is also very well known. There is a huge body of emperical evidence because engine oil producers have long recognized this area of the engine as their greatest challenge, the area of the engine at which specific load bearing is highest and therefore lubrication -- by definition the separation of moving parts -- the most at risk. A mocked up overhead cam engine was even added to the American Petroleum Institute's test process for oil durability rating for this reason. Mechanics know the time of day because they handle engine parts. The auto industry at large knows the score because they had to deal with prematurely worn cams when car engines went to overhead cam design in the 70s. What you see when the cam has worn excessively due to poor lubrication is damage that looks like the cam was turned on a lathe. A dramatic, obvious, cutting appearance, with surrounding areas deeply discolored due to heat. This is not what happens in the Honda V4, whose cams get a more crumbled cheese look.