V-twins are generally (and Harleys in particular) small-bore, long-stroke motors. This puts higher thrust loads on the piston skirts because of the larger anglular displacement, so they need an oil that resists 'smearing' more. Use the wrong oil, and scuffed pistons are the result.
I'll add that one way to tell if an oil is working well is to monitor oil temp. That is one thing that synthetics seem to do better than dino (carry away heat), so if high oil temps is an issue for you, they're worth looking at. The oil is part of the bike's 'cooling system' after all. But if that's not a problem, you won't see much benefit...
I'll add that one way to tell if an oil is working well is to monitor oil temp. That is one thing that synthetics seem to do better than dino (carry away heat), so if high oil temps is an issue for you, they're worth looking at. The oil is part of the bike's 'cooling system' after all. But if that's not a problem, you won't see much benefit...
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