I got the '72 CB350 running today after it has sat in grandma's garage since its last plates in 82. The book calls for straight 30 but it's been years since I've seen that. I put some 5-30 in and figure that'll help clean the crud but I'm wondering what I should use after that.

Ron, if you can't find straight 30 weight then 5-30 is your next best deal.

Ron,

Is that a twin or a 4 cylinder? If its a 4 than you have quite the collector there...

I would shoot the oilman a query on the equipment forum and see what he recommends from Amsoil. But, a quality 5-30 will work great compared to what a straight 30 was back in '72!!!

I would like to see a pic of the bike if you have one. I recently parted company with my old '76 Yamaha RD400 two stroke twin. I miss it, but it was getting harder and harder to find parts for.

If the bike has a common sump - that is, one drain for engine and transmission together, you have a wet clutch.

If a wet clutch, today's automotive engine oils WILL damage the clutch. You absolutely need a JASO MA or MA2 spec on the bottle!

Of oils available today, I don't know of any SAE30 that meets your bike's requirements.

I would recommend use 10W-40 Motorcycle oil - yes, a specific oil designed for motorcycles. AMSOIL has the best - see product data page - also on this page is a link to the test data comparing AMSOIL with many other popular brands.

In addition to Amsoil, diesel engine oil is often used in motorcycles because it doesn't have the same EC friction modifiers as in most oils for gas engines, and usually has higher levels of antiwear agents, afaik.

I've used Amsoil 10-40 motorcycle oil in mine, Rotella 5W-40 synthetic, and Rotella 15W-40.

Be cautious using just a "diesel spec" oil as a motorcycle oil. Diesel CI4+ (without a CJ4) oils are higher zinc and will handle the higher loads in a motorcycle engine. The new CJ4 diesel oils are LOW zinc and not suitable for a motorcycle.

This also applies to high performance 'slider' cam/lifter automotive engines - some say use diesel oil, but the new CJ4 doesn't have what they need.

It's a twin. I don't see many on the streets but they show up on ebay pretty often.

I've read that having incorrect viscosity oil can affect my shifting. It seems like I should get one more shift on the top but I can run it up to 60 mph and still have a decent RPM. I'm in top gear at 40 mph. Being it's been so long in the garage, I don't have much memory of how it used to run.

I've put on about 50 miles. It smells pretty hot. I'm working up to longer trips so as not to risk blowing a seal or gasket. I'm wondering if I should use a conditioner or is the new oil helping.