Oil for 1995 EVO

[dubepj]

Walmart sells Super Tech oil.  20W-50 Meets API SN, SM, SL.  It's pretty cheap.  Doesn't say Motorcycle oil on it.Wonder if this is good for my old bike,  Or should i stay with Castrol 20w-50 motorcycle oil.  thanks

[motorhogman]

Walmart sells Super Tech oil.  20W-50 Meets API SN, SM, SL.  It's pretty cheap.  Doesn't say Motorcycle oil on it.Wonder if this is good for my old bike,  Or should i stay with Castrol 20w-50 motorcycle oil.  thanks

I use that in all my yard maintenance  equipment. I've also used that brand of Gear oil in my trans. Have no issues with it.. I can't say I've ever run it in the bike engine.  I have been using Liqui Moly 10 w 60. If given the choice between Castrol and Super Tech I'd use the Castrol.

[lumberjacklloyd]

Walmart sells Super Tech oil.  20W-50 Meets API SN, SM, SL.  It's pretty cheap.  Doesn't say Motorcycle oil on it.Wonder if this is good for my old bike,  Or should i stay with Castrol 20w-50 motorcycle oil.  thanks

I use that in all my yard maintenance  equipment. I've also used that brand of Gear oil in my trans. Have no issues with it.. I can't say I've ever run it in the bike engine.  I have been using Liqui Moly 10 w 60. If given the choice between Castrol and Super Tech I'd use the Castrol.

Walmart also sells 20w-50 synthetic motorcycle oil that is $5.08 at my local Walmart; I run it in my 111. I would not however run the plain conventional 20w-50 you are speaking of by choice.
https://www.walmart.com/ip/Super-Tech-Full-Synthetic-SAE-20W-50-V-Twin-Motorcycle-Oil-1-Quart/764346752

[Fugawee]

I have a 94' FLHTC that I have used nothing but Castrol 20/50 non-synthetic in, since the 1st time I changed the oil July 1994.  No issues.  I recall reading many an oil article prior to the Twin Cam's about using synthetic oil in Evo's.  Many "experts" claimed that the synthetic would cause leaks at gasket surfaces on Evo's.  That alone made My mind up to stay with conventional oil.
I also have an 03' FLHTCUI that I have used nothing but synthetic oil in.  No issues there as well.  I guess it boils down to what works for You, and how comfortable You are with the results.

[Burnout]

I hate to comment about religious topics, but...       

"Many "experts" claimed that the synthetic would cause leaks at gasket surfaces on Evo's."

This is total BS, this is nothing but pure FUD.

It has been proven many times over that there are advantages to synthetic oils, early on in the game the synth guys made some bad calls and there were some less than stellar results. But years later now this argument really has no place in a non-fiction environment.

Here is my take.
A HD motor is a big air cooled motor and as such is a pretty dirty design. Large internal clearances, and operating in a broad band or temps. Also many of our machines see many short hops, there are as many that are rode with a very happy throttle hand. This puts HDs squarley in the Extreme Operating Zone which requires more frequent oil changes. In this case the motor pollutes the oil faster than the oil wears out, the more frequent changes are needed to get rid of the nasty oil.

Given this the HD motor does not lend itself to extended oil change intervals, Synth oil is not self cleaning.
You could take advantage of extended service intervals if you are traveling cross country, short hops and cold starts are reduced moving you away from the Extreme Service Zone and open the door to advantages of synth.

This opinion addresses only the financial and practical aspects of using synth, there are other reasons to consider synth oil, I am not a chemical engineer just a Mechanic so I'll leave that to others.

[kd]

   I would add that I consider oil also worn out due to contamination.  That is why I use a complete oil change method (Rogue Scavenger system) each time to get that extra duration without remaining contaminates. I will also add that good Syn oil is proven to be much more durable under heat or overheating conditions with a much higher tolerance and shear quality. 

Finally, for those nay sayers here's a test for you.  Take a plate of steel and put a drop of dyno oil on one side and a drop of good syn a few inches away.  Take a torch and heat the area in the center hard.  The dyno oil will run away from the heat and the syn will go toward it.   Think about that next time you complain about the heat off your engine.   

[Burnout]

Thanks KD and that bring to light another aspect of the HD motor design.

Our motors are not so much air cooled as they are Oil Cooled. A very large part of the oil's job in a Harley motor is to carry off the heat.

And this is why I swear by an oil cooler on every HD. And if you read between the lines in the manual this is the way you can run 20-50 oil on 100° days.

[Dan89flstc]

Our motors are not so much air cooled as they are Oil Cooled. A very large part of the oil's job in a Harley motor is to carry off the heat.

The oil may take some part of the heat produced by the engine, but the majority of cooling on a Harley Davidson engine is air.

[Ohio HD]

The leaking wives tale comes from the earlier days in motor history. Vehicles that used non-detergent motor oil would get a lot of sludge built up on the inside surfaces of the motor. Then when a good quality detergent, or better quality synthetic was used, the sludge gets washed away, and under the sludge there may have been a dried up gasket due to lack of oil contact. Then the weeping starts. Also this is when oil pump pickups get clogged from the sludge no set free.

We used to put a lot of oil pickup tubes in cars because of this. Blocked solid from the sludge.