30W Non-detergent - Or is there something better?

sdaigle240 · Post by **sdaigle240** » Tue Aug 04, 2015 9:19 am

naww i dont take offense and i commend anyone's effort towards continuous improvement, i am after all an engineer. i do exactly this with my race car where I try to squeeze everything i can out of her. that car sees 3k miles a year and about 5 oil changes. my dream probably sees 500mi intervals and maybe 500-1000 miles a year. id put 10w30 in her tomorrow and not think twice about it, and have in the past. I just happen to generally grab the old technology bottle which works great, but by no means is "the best". im certainly up for trying different types but i dont have any metrics for quantifying their results (like a pressure gauge) and im a little on the cheap side for doing a series of oil analysis. that would be the end all to the discussion. im a data kinda guy.

http://www.blackstone-labs.com/standard-analysis.php

masonmart · Post by **masonmart** » Tue Aug 04, 2015 9:32 am

Thanks for the comments. Just for info I spoke to a technical guy from Castrol and his recommendation was to use Castrol 1 4T 10:40 (semi syn) or 1 4T 10:30 (fully syn) and to change the oil much less frequently. The handbook for the later CB77's says 10:30 and 600 mile changes and this may be a good starting point.

Far bigger problem though, I have an oil leak around the RH spark plug. I'll have a look if there are any existing threads on this but if anybody can point me in the right direction I'd appreciate it.

MM

G-Man · Post by **G-Man** » Tue Aug 04, 2015 10:54 am

Masonmart

This is a common CB72/77 problem, caused by the cast steel 'skull' in the head separating from the parent alloy. Oil gets between the two surfaces and the way out is via the spark plug threads. Probably exacerbated by a big bore conversion.

There are a number of posts here on the subject but no real cure. Honda published some bulletins to say that it wasn't really a problem at all. I think too many dealers had been relacing heads under warranty and it was getting expensive.

http://www.honda305.com/forums/cb77-oil ... 396-7.html

Interestingly, early C72 and C77 Dream engines don't have the cast steel skull or the problem. I don't think Honda ever used that design again so it was a design change to cure a problem that didn't exist and created one that persisted..... :-(

G

masonmart · Post by **masonmart** » Tue Aug 04, 2015 3:27 pm

Thanks G-Man, I saw a later thread with the Honda bulletin copied and then saw it again on the Bill Silver site.

MM

carabener · Post by **carabener** » Wed Aug 05, 2015 3:29 pm

I ended up here cause I was looking for some gas related mileage (with 15% corn shit added in the usa) that people might be getting all over the world with their CB77's at 60 mph.
So far as oil, since 1963 when my engineer friend and I bought our first new CB77's we have used anything detergent (back then most commonly 30 wt.). With 30-50 CB77's passing through our hands over time, we owned a piece of a dealership, we always used some type of detergent or synthetic. The only thing both of us ever noticed for sure, was that somewhere between 800-1000 miles (usa) we might 'sense' something going on: engine farts, clutch slippage? Bike didn't run as well? Which immediately disappeared upon an oil change. Who the h*ll knows?? Maybe it's all mental. But we both swear to this phenomenon. Maybe it's ghosts in the engine.
The only other thing I can add after my friend bought a machine shop, about 25 years ago we started using a converted oil cooler thing called a heat pipe that goes in and replaces the dipstick. A friend's engineer father who worked at NASA suggested it. And sure enough our mileage between oil changes increased. Maybe delayed oil breakdown? Who knows, we're probably dreaming dreams. You know the kind, "where the dream dreams you and not the other way around..."