[Z15]

I intend to do the same with my BR, but now my dealer says that synthetic oil is fine for BR but that it has to be Honda synthetic oil because of graphite or some other unclear ingredient or reason.

That reminds me of the old saying, if you can dazzle them with brilliance, baffle them with BS.

This is one of my pet peeves. It seems Honda must tell their dealers to push Honda oil because more than one dealer has slammed any synthetic oil they don't sell. I know why do it, they make a lot of money off oil and changing it. They get the customer in the shop and they sell them 100's of $$ in worthless (IMO) services.

See, the Power sports dealers rarely can make it selling the machines, people travel 100's of miles to save $100. They make money in the service and parts depts and they try very hard to get you to come back.

 

[Z15]

If his trans really slipped it was because he chose to use the wrong oil for the application, not just because it was a synthetic oil. My Rincon has over 2,000 miles and 4 yrs of use on synthetic ATV oil and my trans does not slip. Problem is many owners not aware they need to use a special oil, they are of the mind set that all oil is the same.

As a matter of fact, Honda even has a 100% synthetic 4-stoke oil for use in Motorcycles and ATV so the myth that properly formulated synthetic oil cannot be used in wet clutches is just that, a myth.

Pro Honda HP4S
New Pro Honda HP4S is Honda’s first fully synthetic 4-stroke motorcycle
oil and was quite literally years in the making. HP4S is compatible
with synthetic blends such as HP4, as well as regular petroleum
oils like GN4. There is no need to flush the crankcases before
switching to HP4S.
HP4S offers lower friction than conventional oils, better oxidation
resistance for better high heat performance, higher film strength
and quicker flow to vital engine parts at low temperatures, especially
during start up. And best of all, HP4S provides maximum power
due to less frictional drag. HP4S is recommended for use in all 2006
or newer motorcycles, ATVs, Scooters and PWC. It is quite simply
put… our very finest four-stroke oil.

APPLICATIONS
AMSOIL Synthetic 10W-30 Motorcycle Oil is recommended for liquid- or air-cooled 4-stroke motorcycles, scooters, ATVs and UTVs requiring an SAE 10W-30 fluid. It meets SAE 80, API GL-1 gear oil requirements and is recommended for transmissions on both 4- and 2-stroke motorcycles. AMSOIL MCT is recommended for Honda®, Yamaha®, Suzuki® and Kawasaki® motorcycles and scooters, as well as Arctic Cat®, Can-Am®, Honda®, Kawasaki® and Suzuki® ATVs and UTVs. Not recommended where an API GL-4 or GL-5 gear oil is required.