1976 Road Toad 99 lubrication

[brdyer92]

I recently picked up a model 99 Road Toad from a buddy as a project, and I'm slightly unsure about the gearbox oil. I've been told a couple different things and have narrowed it down to belray gear saver 80w-90 (from what I've read on here) or 80w GL-4 oil. I'd love some recommendations, as well as advice on what not to use and why. What is the difference between the two oils I listed above?

I'm also fairly curious about what kind of 2 stroke oil I should use. I have some Maxima Castor 927 as well as some full synthetic Maxima K2. If it makes a difference, if and when I get it running I mainly plan on riding it on the street and trails, opposed to motocross. I'm going into this project totally blind, fairly new to working on bikes and would appreciate any advice I can get, thanks.

[thrownchain]

Make sure what ever brand you use is specifically listed for “wet clutch operation “ .

[ossa95d]

Either of those gear oils should be fine for your application. I would stay away from castor oil for street and trail use as it's a fairly dirty burning oil and tends to separate from the gasoline when sitting. Modern castors are way better than the stuff we used in the 60's though. If you're using oil injection, make sure you use the orange label K2, not the purple. The orange is designed for injector use, and the purple is for premix. Both are excellent oils.

[brdyer92]

Either of those gear oils should be fine for your application. I would stay away from castor oil for street and trail use as it's a fairly dirty burning oil and tends to separate from the gasoline when sitting. Modern castors are way better than the stuff we used in the 60's though. If you're using oil injection, make sure you use the orange label K2, not the purple. The orange is designed for injector use, and the purple is for premix. Both are excellent oils.

Exactly what I wanted to know, thank you. I planned on just disconnecting the oil pump entirely, I've heard tons of mixed opinions but I'd rather be safe than sorry and just run premixed oil. I'll likely use the Maxima Formula K2 at 32:1 or 50:1.

I'm also curious, would it be alright to use hypoid gear oil in this nearly 50 year old transmission??

[ossa95d]

Hypoid gear oil is not designed for wet clutches. It's best suited for gearboxes that accommodate high shear situations like a helical 90 degree. In motorcycles it's usually used in a shaft drive rear hub. Stick with the gear oil specifies for motorcycles with a wet clutch. Every oil company makes one or more and they are all good. Good luck!

[brdyer92]

Hypoid gear oil is not designed for wet clutches. It's best suited for gearboxes that accommodate high shear situations like a helical 90 degree. In motorcycles it's usually used in a shaft drive rear hub. Stick with the gear oil specifies for motorcycles with a wet clutch. Every oil company makes one or more and they are all good. Good luck!

Thanks!