Letter Re: Advice on Engine Oil for Motorcycles

I’ve been reading your oil/energy columns. Very informative, thank you. It seems I am getting some less than adequate answers to my question posed to my local motorcycle dealers.
I have two motorcycle’s (both about 45-50 mpg). Buying ‘motorcycle 20W-50 oil’ or “Harley Davidson [brand] 20W-50″ motorcycle oil is more expensive versus just 20W-50 oil. If you have time, is all 20W-50 the same or should I pay the extra at the motorcycle shop since motorcycle engines run at higher rpm’s and the oil does need to have whatever makes them more resistant to the heat and stresses associated with motorcycles? Thank you, – Pete

JWR Replies: Oil brand names make very little difference. As long as the oil meets the industry (SAE) specifications, there is little or no advantage in buying a “name” brand. I’ve read that motorcycles utiilize a wet clutch which has much less surface area than an automotive drivetrain, so you should use a “motorcycle blend” with appropriate additives to prevent clutch slipping. But there is no need to buy the “Harley” brand.
In my opinion, a much more important question is: traditional or synthetic? The price of synthetic motor oils have come down in recent years. I recommend them for many applications.