80 weight gear oil is about equivilent to 40 weight motor oil in viscosity. As long as you are careful not to use the newer energy saving oils, the motor oil will be fine. The newer energy conserving oils have super-slippery additives that are not very clutch friendly. For what it's worth, I use ATF type F in my tranny, and it works just fine.
Spanky that ATF tranny oil won't hurt it? I was thinking about running a little through mien and then draining it after a ride just to clean it out reall well. That stuff does an amazing job for cleaning carbon and gunk. Would it be alright to use like Dexron II or III?
I run Spectro Clutch Saver 10w 30 in mine. 97 CR 250 & 89 RMX 250.
I have NEVER had to rebuild the clutch in either bike.
And it shifts real smooth.
The price is about $5.00.(cheeper if you buy it by the case)
I know you are looking to save money. I belive that it has saved me money in the long run.
Just my .02 cents
Originally posted by RM250Rida Spanky that ATF tranny oil won't hurt it? I was thinking about running a little through mien and then draining it after a ride just to clean it out reall well. That stuff does an amazing job for cleaning carbon and gunk. Would it be alright to use like Dexron II or III?
ATF won't hurt your tranny at all, as long as you run only type F ATF, and change it regularly. Don't use Dexron. If you think about it, an automatic transmission consists mainly of gearsets and wet clutches. Sounds like your bike tranny, doesn't it?;)
I have run Type-F ATF in the winter and Mobil-1 15W-50 synthetic in the summer with no problems in a '00 CR250 and two '01 CR80's.
The Mobil-1 15W-50 is a NON Energy Conserving (EC) oil so it doesn't have the friction modifiers that some other *regular* motor oils have.
As far as car oils, almost all 5w30 and 10w30 have the "EC" (energy conserving) additives in them. If you check the bottles they will have an "EC" insignia on the back.
10W40, 20w50, and SAE30 do not have the "EC" additives or the insignia on the back of the bottles.
Although I do use 2-stroke specific tranny oil now (Spectro 80w and Champion 80/90w) I have used car oil and ATF type F in the past with no problems.
My '87 Honda CR 125 manual said to use 10w40 in the tranny, on the air filter and on the chain.
My '92 KTM 250 Sx said to use SAE 30 in the tranny. And my '95 ATK 250 cross country said to use 20w50 in the tranny.
If I were to go back to using car oil, I think I would use an SAE 30 or 40 weight due to there non-"EC" ratings.
I can't tell the difference in wear, shifting, or clutch performance between car oils and 2-stroke specific tranny oils.
Just my 2 cents worth from my 23 years of riding.
The main difference between your dirt bike trans and an auto on a car would be the fact that the bike has gears that engage/disengage, while the auto uses planetary gear sets (always meshed), clutch packs, and friction bands to change speeds. Gear oil, such as that used in most manual transmissions (80W90, etc.) would have greater film strength and in theory do a better job of protecting the gears.
I'm not trying to say that it's bad to run ATF in the tranny of a bike, I've used it on several bikes without a problem.
The part that really confuses me: my mustang calls for ATF in the T-5 manual transmission!
I'm a bit confused on why an oil called "clutch saver" would be designated as a 10W30...sounds like it's designed specifically for bikes, but I wouldn't think there would be enough difference in operating temperatures in a dirt bike trans to need a multi weight, and non-multi weight oils tend to perform better (under certain conditions, anyway). Multi weight oils contain extra polymers.