Using regular 20w-50 oil
When I'm not riding an HD, I'm flying an airplane. My air cooled, turbo charged, piston engine airplane routinely sees CHTs in the 380 degree range. In the plane I use AeroShell 15W-50. I have a drum of it in the hangar so I've used it in my HDs for years and never had an engine related break down on the bike or plane. Regarding using auto oil, suit yourself, but I prefer using an oil tested for the kind of temps seen in a mc or airplane. Cars typically run in the 240 degree range.
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Joined: Mar 2009
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From: Niles Canyon Ca.
When I'm not riding an HD, I'm flying an airplane. My air cooled, turbo charged, piston engine airplane routinely sees CHTs in the 380 degree range. In the plane I use AeroShell 15W-50. I have a drum of it in the hangar so I've used it in my HDs for years and never had an engine related break down on the bike or plane. Regarding using auto oil, suit yourself, but I prefer using an oil tested for the kind of temps seen in a mc or airplane. Cars typically run in the 240 degree range.
I
Living here in the Midwest where temps run 50-80, I like the 15w50 and run the 15w40 Rotella T in the KLR 650 all year round. Some of the folks have made the switch to Rotella T in their Big Twins also. . . . I may do it too ?
JMHO
Last edited by Willie D; Jan 22, 2012 at 05:53 PM.
Banned
Joined: Dec 2011
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From: Arizona
So now what?
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Why are people using diesel oil in their primaries?
What other oils are good for the primary?
I have read threads about guys using simple tranny fluid for the primary however I have never tried it. I use rotella t 15w-40 in my primary. Diesel oil is high in detergency and my reasoning is that it keeps the clutch plates clean. It also carries the JASO symbol which means it's safe to use in shared sump bikes. So if it's ok in those bikes which the clutch shares fluid with engine I believe that it's ok for my application. I save the big ticket oil for the engine,which I am sure I don't need but I sleep better knowing it's in there.
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From: Honah Lee
Mobile 1 on sale from NAPA but it's 15-50. Moble 20-50 is the motorcycle grade. Never seen it on sale. You need to go on Mobile's site and compare the difference. I just putt around town so Wesson oil would work for me. Waste of time to get facts other then opinions on here on oil and can be dangerous on brake fluid.
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Joined: Jun 2007
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From: Richmond, VA
I used to worry myself sick about synthetic vs conventional vs semi synthetic....... then I realized that I have never left oil in my engine long enough that is would make a lick of difference. I change my oil way to often because I just like to. Its one bolt and a spin off filter. Takes maybe five minutes. Why worry about it??? But thats just me.
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