Synthetic oil and Motorcycle engines

I have a friend here that I work with the has been riding sport bikes for years. He has put over 100k miles on 3 different bikes and the oil he used in them was Mobile 1 synthetic.

I am not referring to the Mobile 1 made for bikes, he uses the same stuff he puts in his cars. I have ridden for a few years myself but have always heard that you can never put automobile oil in motorcycles. No matter what kind, synthetic or not.

Maybe some of you can shed some light on this for me.

I ride a 2005 Shadow Aero 750 and have gutted the stock exhaust and fit it with a Kuryaken Hyper charger. It gets pretty good power from this configuration but I would like to get the protection benifits from Synthetic oil. I Just can't force myself to pay 12 bucks a quart for full syntheetic bike oil.  

The only people who say "Never use automobile oil in a motorcycle" are people who sell motorcycle oil. I've been using automobile oil in motorcycles since the 70's.

If you have an air cooled bike, it's better to use automobile oil that's rated for use with turbocharged engines, simply because it can handle higher temperatures better.

If you have a wet clutch, you want to avoid any oil that includes 'friction modifiers' in the description or that says 'energy conserving' in the SAE circle. Those oils are reputed to cause the clutch to slip. You generally don't see those in anything heavier than 10W40, so I've never had to concern myself with that.

Other than those, the only times I've heard of oil causing problems is when someone used the wrong viscosity or ran a race oil without detergent additives.

regards,
Joe  

I recently purchased a Yamaha 950 cruiser.  I changed the oil the first time after only 30 miles following a prescribed (non-Yamaha) break-in technique to get rid of any metal.  I continued with the Yamalube 20W-50 oil until the 600 mile check.  At that time I switched to Yamalube synthetic 15W-50 which my mechanic said would be fine.  A friend of mine who has been riding for many years said it was more common to wait until the engine had several thousand miles on it before going synthetic.  Any thoughts on this?  

Thoughts, eh...

I have read claims that today's motorcycles have a much finer pattern of scoring in the cylinders when new and consequently they are fully broke in before ever reaching 100 miles. Somehow, that doesn't correlate to my recent experiences with a 2005 kawasaki and a 2007 honda. Both of those bikes ran well from the start, but at around 13,000 miles they both suddenly increased their mpg by an additional 5 mpg and both of their oil usage patterns changed then also. The kawasaki oil usage decreased sharply at 13,000 miles, while the honda oil usage increased slightly. That seems to conflict with the idea of the engines being completely broke in at some earlier mileage figure.

regards,
Joe  

I Sell Automotive and Motorcycle Oil. I have researched the difference. You must read the Back of the container, and learn the API Services rules. All Automotive engine oils rate (or use the letters) SM today... what you want is anything that has an SL rating or lower...this is due to the technology difference built between Automotive and Motorcycle engines. Also you have to pay attention to bikes that have a wet clutch...(means the engine oil lubricates the clutch)(almost all modern bikes have this) Moly lube is what I have found out that is very good for the wet clutches... I like Royal Purple because of this fact... I am trying the 15w-40  and recommend this especially for availability (in my Suzuki C50) the regular (automotive) oil is about $9.00 a quart and the Motorcycle oil is about $14.00 a quart... You should really make your own choice and talk to your favorite mechanic...  

I hear Amsoil is the very best to use for a bike.