Castor is typically better for air cooled engines. It's definitely not ideal for water cooled and power ( exhaust) valved modern high tech 2 strokes. A chainsaw is air cooled and have no exhaust valves. That said, 927 Maxima is known to be a pretty dirty oil. It tends to have a lot of residue like was shown earlier. From maxima regarding temperatures and separation. Caution Not intended for use in oil injection systems. When blending with alcohol it normally requires more oil. Care must be exercised when blending with low specific gravity (below 0.730) race gasoline or aviation fuels and in temperatures below 35ºF as separation may occur. Separation may also occur in alcohol containing a high percentage of nitromethane. Check before using.
If you want a great smelling synthetic saw oil, use amsoil sabre. It smells like 2 stroke race gas. I don't do their 80 or 100:1, but rather 50:1 in asl my 2 stroke non oil injected engines. I just found that sabre has a fuel stabilizer in it. That's good. SABER® Professional Synthetic 2-Stroke Oil
I will say that amsoil dominator and interceptor smell great and more importantly keep the combustion chamber and exhaust valves clean and not gunked up on my Polaris XC sled. That was a first year engine and the oil pump was set rich from the factory that year. The Polaris exhaust valve oil would gum up the valves in short order. I could run a whole season and still not have any gummed up non properly functioning power valves with dominator or interceptor. Keep in mind I think those are both really formulated for water cooled 2 strokes. The sabre smells even better IMHO, and it's actually designed for chainsaws which are air cooled. I won't run an oil for water cooled engines in an air cooled one, and vice versa. Not unless I have no choice.
None of the Amsoil products are actually certified as being for air cooled or water-cooled engines, at least that I’ve seen. Saber says on the bottle it’s designed for air-cooled engines, whereas Dominator says it works for both. There are several dedicated air-cooled oils being tested that didn’t do very well, even though they were fd certified, which is why he’s doing the testing. Doesn’t really matter to me what product may or may not carry all the hype as long as it does it’s job and doesn’t build carbon.
Well, both dominator and interceptor are designed to be used on engines with power valves. That tells me a lot. Both say they are good for all 2 stroke snowmobiles. Since saber is designed for chainsaws and other like equipment, that's what I'll use. I think dominator or interceptor are a bit Overkill for saws.
This is the oil I've been using in both of my huskihl ported saws. Running about 40:1 now. Seems to be doing good.
Kevin seen the piston and cylinder off my 026 (I had not cleaned them at all) very little carbon on either. That saw has seen Husky semi synthetic, Poulan pro, Belray H1R, , Quaker State (emergency) Red armor and a few I can't remember including some boat oils (more emergency). That saw has seen some use, A guess would be 1,000 cord or so, it was clean. Compression dropped to 175psi on my gauge and rings were worn, I think a bunch of below 0°F starts and a bad air filter were the cause, but also some use (I don't think oil had a lot to do with it). I mix @ 32:1 also.
I don not recommend oil with castor for use in a saw, except for extreme use like milling, and even than it can gum things up bad. Any good straight synthetic will more than do in a chainsaw. 927 smells awesome in small doses, breath too much and you'll be sick.
A youtuber did a wear test comparison between Dominator and synthetic supertech. There was an obvious difference in metal wear. I tried everything in my CR125 before exclusively using Honda hp2. It took several applications of oven cleaner to get the castor off the head. Used hp2 in my saws too when I had the cr.
My experience with castor is with kart racing engines and castor is extremely popular in water cooled when allowed by rules because the cooler head temps reduces carbon acumulation in the combustion chamber. Castor is also popular in air cooled but care must be exercised where combustion chamber volume is limited.
In certain situations, yes. Aren't you also regularly tearing down cart engines ( shifter carts using motocross engines?). If you are regularly taking the engine apart and cleaning all components, this is less of an issue. 2strokes are a fickle beast and require tuning for minor changes, at least for optimal power. EFI helps a lot but adds complexity.
You question was "aren't you regularly tearing down cart(proper term is kart) engines" and that was addressed in my 1st post.
I'm not really sure what the debate is. Let's review. I stated that castor is an excellent lubricant but there is extreme carbon buildup in air cooled engines which imo is not suitable for chainsaw applications. I also stated the carbon buildup isn't an issue with water cooled kart engines (all water cooled kart engines aren't shifters) due to lower head temps. Tell me what we're debating here because I'm lost.