Marvel mystery oil

i wouldnt put it in your fuel. and no need to on a 4stroke. i think sometimes its used as a fogging oil, or in transmissions

Marvel Mystery Oil claims to be a cure-all for lots of fuel issues. When I was a kid in the mid-70's my dad had us put a little in the lawn mower gasoline. I think there are lots of "motorsport-specific" fuel additives, that are a better product , today. (VP, Maxima, etc) You probably don't need any additives, but if your bike tends to sit, for a few weeks a fuel stabilizer is a good idea.

I'm a same era dude as mxracer. My Dad ran an R&D engine program for Onan/Cummins (and his love of engines is what got us into mx, boats, snowmobiles, and jet skis). In this era, there were a TON of advancements occurring in the petrol industry as well as manufacturing and materials. To combat the deficiencies in fuel lubrication and oils of the time (e.g. 2-stroke pistons would commonly scuff), my Dad and his engineers had 2 go to products they used to ensure engine life/reliability + maximum power generation (ring seal):
(1) Seafoam
(2) Market Mystery Oil

Oh, and they looooved Bel-Ray products (Maxima didn't exist yet).

I also agree with mxracer that industry specific products that have been developed since and are likely better. I am a diehard fan of Maxima and Bel-Ray (based on the lubrication performance I've personally witnessed), but ... guess what ...?

I use a batch (in 5 gallons of gas) of Marvel Mystery oil and Seafoam every ~ 6 months to clean the fuel system. Honestly, it's part superstition likely, but I have saved the day many times with these products in the past to clean up a gummy carb on a snowblower or a lawnmower. They DO work. Lastly, given our fuels generally don't have lead anymore, my Dad was very pro Marvel Mystery Oil to assist with lubrication for this reason as well. He also really like its upper cylinder lubrication qualities as well (valvetrain) and used it to this day.

Lastly, lastly - I can't imagine any race teams using it, etc. My honest feeling is it may be obsolete for the primary reasons it was originally used, but again, I like it as a fuel system stabilizer and cleaner.

And FWIW, I run fuel stabilizers continuously to keep problems due to fuel degradation at bay.

I am not buying the BTO mystery box, and I'm not using anything called "mystery oil" in my bike.

You're not living, man!

Where's your sense of adventure?

Honestly the first time I heard about it was when I was sending my cylinder off to millennium to be replated. They recommend using it for initial seat as mentioned above by Rider. So I picked a couple up for that.

It’s awesome for lubricating air tools. Motorcycles not so much

I found this shootout comparison interesting:
https://youtu.be/J3F3jDa2xhg

"Marvel Mystery Oil" ... what a name, right? Eeesh.
I guess it's like "Google" today. We'll be looking back on that and saying "WTF, that's what they named a multi-billion dollar company?!" Whatever, it does still seem to have some compelling positives.

The fact that Millennium recommends Marvel Mystery Oil is extremely interesting. Their business is all about reputation - and if their engines aren't kicking a$$, they don't get repeat business.

My Dad always put it this way relative to the engine tricks they arrived at with experiments:
"BIW - because it works!" He straight up wasn't sure why each product excelled, he only knew they did something positive per the dyno and wear measurements after teardown.

Used mystery oil, just about all motors. Diesels (drilling rigs, air compressors), residential (mowers, tillers, sled, motorcycle, vehicles). To loosen bolts mix 50/50 mystery oil/diesel. In short “I put that Sxxx in everything”.

Use it in my welder once in a while works great