Scale wrote:
Thank you!

Yeah Michael, they weren't against it(synthetic). They said what you said about it all 'mating' and 'seating' properly, and perhaps using synthetic after a good break in(hehehe). Thatz interesting what you said about those friction modifiers. I'm assuming YammiLube(non-synthetic) doesn't have those in there????

docrok wrote:
That is correct. The thing to look out for is the JASO MA certification on the back of the bottle. That signifies that those oils are specifically engineered for motorcycle engines, and are safe to use with wet clutch applications.

With the exception of most Ducatis, Moto Guzzis and BMWs, most motorcycles have a wet clutch. In a wet clutch, the clutch plates are immersed in oil. Some oils make the friction plates in the clutch slippery so that the clutch doesn't engage properly when shifting gears, or the clutch slips when the engine exceeds a certain torque. Some oils contain friction reducing chemicals. These oils are unsuitable for motorcycles. All 5W20 and 10W30 non-motorcycle engine oils have these friction reducers. Oils with an operating weight of 40 or greater are not required to have friction reducers. These oils are unlikely to cause clutch slippage.

One element of the JASO-MA standard is a friction test designed to determine suitability for wet clutch usage. An oil that meets JASO-MA is considered appropriate for wet clutch operations. Oils marketed as motorcycle-specific will carry the JASO-MA label. Other oils, such as Shell Rotella T heavy duty engine oil (HDEO) carry the JASO-MA certification.

A properly specified motorcycle oil will still allow for the appropriate lubrication and cooling of a motorcycle clutch, whilst maintaining 100% of the drive to be transmitted by the clutch, even under arduous operating conditions.

If it has a picture on the back that looks like this, avoid it!


I stole some of that text from Wikipedia because I didn't feel like typing it all, lol.

Oil wars is right ! Is there a real right answer ? I don't really know myself . I will tell you this on my gen 1 with a Barnett clutch conversion kit full syn will make it slip but semi is fine . My Busa after the motor build from Carpenter he had my use Amsoil 10w30 Domanitor Full race oil even though it is not approved for wet clutch motorcycles . I did not like the Idea of this but was told that with the Very high lift cams in the bike he wanted them well lubed and that in all the years or motor building and use of this oil he had no problems . I did get 2 years out out the clutch so far with many passes at the drag strip and it's been just fine. I do change the oil every 1000 miles or so dependent on how hard the bike is ridden or how hot it got at the track

Amsoil...been running it since the 600 mile service (My local Yamaha dealer actually recommended it). I flogg the bike hard on regular basis...stock clutch, no DD mod...no slippage or any other issues what so ever!

Amsoil White Paper

Great White Paper on Amsoil

I have been using Sikolene full synthetic is been good so far but expensive used much in Europe
in the racing circuit +1 it's blood red and looks awesome in the OTEC Cases

Blackmax98 wrote:
All bikes made in Japan call for 40W.I don't care who built your motor, he's wrong to reccomend 30W.

As TFW stated, 40W oil doesn't use friction modifiers.Almost all 30W does.If you want it well lubed just use any full synthetic that's 40W.

I have Shell Rotella 15W40 in the Max now & I'll change to Mobil1 full synthetic 10W40 for high mileage in the spring.I use it in the Busa & Warrior also.I get it from Wallyworld because you can't find it cheaper anywhere unless you know someone who works for an oil company.About $21 for 5 qts.Amsoil is the best but good luck getting it for that price.

HoosierBusa wrote:
I really think that Bob Carpenter who has built 1000's of Race moters knows his stuff or Ricky G would not have all his bike there too , but as stated before everyone thinks they know the "Oil Answer" do you think you have the right answer? I will go with The Builder

I've been using Amsoil in my GEN I for 6 years. No problems. 1200cc and 1500cc applications. The bike runs much cooler. ONLY draw back is if you have a small oil leak with conventional oil it will show greatly with synthetic.

I've been using Amsoil in my Gen II now for almost 1 year. I haven't had a problem yet. I use Amsoil in every automobile that I own. It's worth every penny.

As long as you have a good clutch it will NOT slip. If you use synthetic with a worn out clutch you will find out really quick that you need a clutch.