Mixing Two-Stroke Premix 100:1 Into Gas???

4 replies to this topic
  • i_wheelie_longer

Posted June 26, 2010 - 05:41 PM


Anyone add a tiny bit of two stroke synthetic premix oil into their gas for their 4 strokes? A couple people I know add premix 100:1. Is there any negative effects of this? Or is it more beneficial with a little extra lubrication for the piston, cylinder, valves, and valve seats? The bikes don't smoke or anything, and be mindful I'm not saying to mix oil like you would on a two smoker.... just approximately 100:1. Any thoughts?

  • zukboy789

Posted June 26, 2010 - 05:45 PM


I wouldnt because there is a reason it takes straight gasoline. ANd second, you may get deposits on your valves, etc....

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • grayracer513

Posted June 26, 2010 - 07:01 PM


This tactic is an old one, dating to before the second world war. It's called "top oil". It has some benefit when using a "dry" fuel, such as some racing fuels or alcohol, since the compression rings are lubricated only by fuel in a well built engine.

But it's not as important as it once was, and isn't required at all with most pump fuels unless you run E85 (shame on you). 100:1 is too much, anyway. 200:1 is more like it.

  • davek18

Posted June 26, 2010 - 07:57 PM


The oil mixture in the fuel actually reduces the octane rating a smidge too, I have used premix in my 4 stroke in a pinch with no noticable effects, but I see no reason to intentionally do it. Oil fuel mix has a shorter shelf life too, burn it all up if you use it, don't let it sit for weeks in the tank.

  • SAthump

Posted June 29, 2010 - 11:04 AM


I run redline fuel system cleaner in my gas. It lubricates, cleans and helps prevent knock. Been using it for about 13 yrs works great.

Related Content


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.