I have a friend of mine that has a few cases of old school gtx racing 20w50 racing oil I'm sure it has zinc in it will this be a problem in a 103 twin cam? Btw I do not run synthetic now I'm thinking the zinc content would be good for the bearings. Any opinion?

 

If it is five or more years old dump it.

 

Use it in the engine Don’t dump it

 

Why is that I'm sure the are all sealed

 

^^^...or fill the chain saw reservoir with it...^^^

 

Why would you say dump it ? It's not a 5 year old can of beer !

 

use it. all of the "V-twin" motorcycle oil you can buy off the shelf right now has a ****-ton more ZDDP than motor oil for a car. Bikes don't have post-cat O2 sensors, so if the phosphorus poisons the cats no one is the wiser.

edit: to clarify, as far as the engine is concerned, zinc (ZDDP) is a good thing because it's a potent anti-wear additive. ZDDP has been progressively reduced from car motor oil because it can make its way into the combustion chamber and poison the catalysts. and cars have downstream (post-cat) O2 sensors to make sure the catalysts are working.

 

If you knew how long it sits around in giant tanks it wouldn't matter. Have you ever seen an expiration date on a quart of oil?

 

What is the SAE rating and does it meet the diesel rating that Harley specifies? Many Racing oils have a limited additive package and aren’t meant for a street bike. Ya might get away with using it but wouldn’t go more than 1500 miles ona change.

 

?????
Oil in a sealed container has no expiration date.