What oil should I run?

I just bought an 83 kz650, and with all the bikes I buy I go through them all an inspect them. This is my first running inline four, had a gs550 I never got running. I have had twin and single cylinder Honda's. I ran Bel Ray in the twin cylinder and the single, then Motul double ester blend. What do you recommend running in the kz? It has 33,000 miles and is in good shape. I usally run synthetics in my bikes, they just seem to hold up well. Lets her what you have to say.

The brand is not important, only that it is one specifically formulated for motorcycles. I also only use dino-based oil in my older bikes (Valvoline 20W-50), but some folks maintain that synthetics are OK. I use a syn in my newer H-D, but never had a problem with fossil oils in the last 40 years.

Dino oil is fine. Check out this website: www.bobistheoilguy.com/cms/
All the oil info you could ever want from guys who obsess about their oil more than you do about your bike.

I'd not recommend any of the "Car Oils" as they have friction modifiers that is not compatable with our wet plate clutches. This is one way the car manufacturers can get the EPA mileage standards for a gallon of gas.

I believe it's led to clutch problem and trouble with the over running starter clutches too.

Yeah, def. no car oil. However, many diesel oils are compatible. No friction modifiers there.

on the filler cap there is the numbers that'll match the oil you wanna run....change it all the time and change the filter every other change and you will be fine....the rest is smoke and mirrors...

Most motorcycle forums have expressed good luck with the diesel oils, 15w40 shell rotella-T, chevron delo, castrol textron, mobil delvac ect. I've run Rotella for many years. Look for the energy conserving label on the bottle and if it's there don't use it. Most car oil even if non energy conserving has had most the zinc removed from the formulation, so it's questionable as to the suitability of use, the diesel oils still have about 1100ppm of zinc. Motorcycle specific oils have for the most part been addressed as just an extra money expenditure with no advantage over the diesel oil if you read bobistheoilguy forums and the various analysis guys have done. 15w40 is too thick below about 40 degrees so if you ride all Winter it won't be a good choice, 20w50 is too thick below about 50 degrees.

Read this thread. It contains much info on oil to use in our KZs:

KZRider Oil Discussion

Her's my recommendation. I've been using it in my KZ650C1 for years and I'm very impressed.

Mobil1 Racing 4T 10W40

My understanding of the reason why Zinc was removed from the car oils is that it kills/reduces the catalytic converters on cars. Diesel engines don't have them(yet).

AMSOIL 20W50 Full Synth.

Desined for wet clutch/air cooled bikes.

Change once a year.

AMSOIL 20W50

Amsoil Syn and Rotella Syn have the best reputations on the net. I have never heard a single unhappy post on them.

MFolks wrote:

My understanding of the reason why Zinc was removed from the car oils is that it kills/reduces the catalytic converters on cars. Diesel engines don't have them(yet).

Correct, the EPA basically threw flat tappet engines under the bus so that cat converters would last 150,000 miles instead of 100,000.