My 1984 1/2 EVO has roughly 45,000 original miles on it. The drivetrain has never been touched. The last owner (19 years) ran nothing but HD oils in it. I'm thinkin I would like switch over to synthetics, especially in the original 4 speed tranny. Any thoughts or experiences with synthetics vs Old Iron?

 

There is a chance that using synthetics could lead to leaks due to the age of the seals, so if it were mine I'd keep using the HD oils that were used in it up to this point. (I assume HD360 dino.)

Considering the HD oil has gotten it to this point with nary a hiccup, and will likely take it another 100k miles with no problem, why change?

 

I agree with the lost 1. the best time to use synthetic is after the motor is broken in. your bike has been around the block a few times. sure you could use it, but it would be like closing the barn door after the horse ran off.,,,

 

I would not use synthetics in that bike because seal materials during the era when that bike was made may not be compatible with synthetics. Stick with the HD dino lubes. If it aint broke....don't fix it. IMO

 

I would not go looking for trouble. Dertergent levels are high in the modern synthetics as well as it will find any weak spot in the sealing to weap out of. Your bike will have a long happy life with the oil type it's had since new. High heat is not going to be an issue with yours, which is why many of us use synthetics anyway.
Ron

 

Well, I don't see any particular problem with synthetics, especially in the transmission- a syn gear oil, of course. Don't see any problem with regular motor oil either, except I wouldn't use Harley's- too expensive. I use Kendall myself. 130K on my Evo.

 

Thanks for the imput guys, I wasn't even thinking about the seal issue. I am definintely sticking to what has got me to this point. Anybody have a thought on what might make the 4 speed tranny any smoother shifiting? Appreciate the imput.

 

Try a clutch adjustment. Usually that'll do more than anything else to ease the shifting.I might try Redline HD shockproof in it, if it was me.

EZ