Correct the Mystik JT8 is a diesel oil. Meaning they recommend it for diesel (up to) CJ4 applications and on the 2 gallon jug it has gas (up to) SL applications. BTW- my 103 HO engine calls for diesel if Harley oil not available. The Mobil doesn't have a diesel recommendation on it.
As far as the Mobil 1 20/50 Motorcycle oil, its not an oil I want to use, has no value in it for me. I do believe they are all good but cant see spending 300% more money for an oil that doesnt meet the specifications (or at least come close) of the people who built my engine and honestly cant see spending that money on an oil I am going to throw out in 3,500 miles or less.
I dont chose by the amount of "anti wear ingredients" I try to follow the manufacturers recommendation or at least close to it and the price to me certainly isnt worth it.
The Mobil 1 15/50 at least has mention of an outdated diesel rating of CD on the website (or did), not close to Harely specs but at least its there.
Glad you posted, you know, I look back at the UOA and think to myself that Mobil 15/50 certainly turned some good numbers, in the same riding conditions, the Mystik numbers are great in themselves and the Mobil 1 15/50 even better. I just bought 4 gallons of JT8 though and I am back to using it, I do use JT8 in our boat as well. Who knows, maybe I will try Mobil 15/50 again someday. even though wear is less, at least what the UOA shows, the engine is more noisy with the full syn vs the semi JT8, not that it should matter but well ... you know ... ? *LOL*
Ahhh... the 103 HO engine on ny Road King. Good god yes! I am glad to read your comment from the mechanics. Its a MAJOR sticking point for me on the new Harleys. The 103 is a mature engine, refined over a number of years.
Riders love their new M8 engines until sadly one of a few have an issue and for some reason HD has not been able to fix some of the issues completely really leaving some people stuck. I dont know but that sucks, that's going back to when they came out in 2017, now here we are in 2021 and Harley changed the entire engine management ECM to another company with completely different firmware, not unusual for them to do just seems weird as they were still getting issues settled.
Anyway, maybe Im getting older? Maybe Im not rich enough? *L* But I dont know, the bike I have is spot on reliable, still hasn't needed a repair, has no issues at all and I just cant bring myself to or wanting to "upgrade" to the same bike again for what must be close to $23,000 or more. We walk in showrooms all the time but nothing gets me going on any of the new models, including the colors, then look at my "old" bike and think, wow I like that bike.
HD prices, maybe I feel I cant pay anymore... I was thinking a complete switch to something like a Concours 14, pick one up new for around $14,000 but doubt any of this will happen ... and keep enjoying the RK... which my wife also wants me to keep because its super comfortable
for her on the back ... photo is Smoky Mountains Gatlinburg TN Trip - Aug 2020 I think this photo we were on our way home, rest stop on the NC border.
I also have a back rest and luggage rack that snaps in, in place of the slimline trunk when not traveling or whatever.
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