What happens if u put 2-stokre mix gas in a 4-stroke?

24 replies to this topic
  • x2468

Posted July 08, 2006 - 08:59 PM


i haven't done it, but im sick of throwing out my mix gas when i make to much or something. i heard once it does nothing if it goes in a 4-storke but wanna make sure before i throw it in the lawn mower or something.

  • RLthumper

Posted July 08, 2006 - 09:00 PM


just kidding, nothing will happen. worst case scenario: you foul a plug.

  • Chickenhauler

Posted July 08, 2006 - 09:13 PM


I burn up our old 2-stroke gas all the time in my DRZ, lawnmower, PU, tractors, whatever needs gas. (The only 2 stroke we have is a KX60 that doesn't get ridden alot) Nothing will happen, MAYBE foul a plug, but the chances are slight if you're running 32:1 or leaner. I wouldn't reccomend it in a newer car/PU due to the sensitivity of the vehicles sensors.

If anything, mixed fuel will provide extra valve lube to a small engine.

No damage will be done.

  • x2468

Posted July 08, 2006 - 09:14 PM


i dont have a 4-stroke bike. but i was gonna put it in my mower or maybe car.

  • 7d7

Posted July 08, 2006 - 09:14 PM


ive run mix gas in my 2.3 horsepower mower and all that happend is it smoked alot. as far as a high tech finely tuned mx bike? im not shure,but imo i dont think it will do any serious damage.maybe just dirty things up and make it run like crap and dirty up your carb maybe. how ever i wouldnt try it with a $7K machine. a $200 mower is a different story.

heh ive gone so far as to run 101 proof alchohol in my mower and it ran fine.

  • crfmxer

Posted July 08, 2006 - 09:29 PM


what will happen? it will smoke and you will get carbon buildup/deposits on your piston, sparkplug, head, valves and exhaust ports. all depends on how often and how much mixed gas you use, a little once in a while won't hurt anything.

  • punkrock MX

Posted July 08, 2006 - 10:47 PM


it'll make the plug dirty but give you some extra lube and smoke alittle..cant really hurt that much if at all

its not a good idea to put it in a car due to the fact the unburnt oil may clog up the 02 sensors on the exhaust and whatnot

  • Martys

Posted July 09, 2006 - 05:50 AM


I put my extra 2t mix in my vehicle with 1/2 tank of gas (or more) The mixture is so diluted that nothing bad will happen.

  • qwik-E-02CR

Posted July 09, 2006 - 07:41 AM


nothing willl happend. we've been putting it in our cars, lawnmowers, ect and nothing happens. all it does is add extra oil. dont even worry about anything.

  • sxy rider 39

Posted July 09, 2006 - 08:54 AM


It will smoke.

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  • crfmxer

Posted July 09, 2006 - 09:53 AM


obviously none of you have torn apart a 4 stroke motor that has been run with mixed gas. it plugs it up, don't make a habit of using it.

  • qwik-E-02CR

Posted July 10, 2006 - 10:04 AM


obviously none of you have torn apart a 4 stroke motor that has been run with mixed gas. it plugs it up, don't make a habit of using it.

obviousy you didnt understand the question.

dont run mixed gas all the times in one, but its completely safe to use it here and there. theres no damage. and yes ive seen a couple of motors that were run on mixed gas. i took apart my dads old lawnmower, it was fine. he ran that thing on mixed gas left and right. when i rebuilt my toyota, that thing was completely fine, not plugged up at all. weve been putting our extra gas in our cars and jeeps for X years, not a single problem. :ride:

  • Motocross26

Posted July 10, 2006 - 10:21 AM


I've put some old premix in my lawn mower a few times. It seemed like it ran cooler with the premix.

  • velosapiens

Posted July 10, 2006 - 10:29 AM


im sick of throwing out my mix gas when i make to much or something.

&%$#@!? how can you make too much? do you only ride once a year? :ride:

i mix 5-10 gallons at a time. when i run out, i mix more.

  • agent32

Posted July 10, 2006 - 10:43 AM


If you run mixed gas in your 4-stroke it will sprout magic wings and you will be able to fly around the track

  • barefootbob

Posted July 10, 2006 - 11:57 AM


I try to use it in my weed eater 1st,I have used it in my powerwasher,actually makes it run a little hot because your running a lean fuel.Your jetted for strait fuel and by putting oil in the fuel your burnning less fuel so that would make you lean.

  • snowxdadx3

Posted July 10, 2006 - 12:01 PM


If you run mixed gas in your 4-stroke it will sprout magic wings and you will be able to fly around the track


  • greatpunkin

Posted July 10, 2006 - 12:25 PM


In an on-road vehicle it will foul the catalytic converter. You may have to replace it if you do not meet the DMV smog test. In Calif its every two years for smog testing and certification. If you mix a little in bikes-small motors it will not do damage to anything. You won't foul a plug (2 strokes would never run if that happened) you might build up carbon on the valves and piston. As long as you have a good burn out afterwards with non-mixed gas it is no big deal.

  • Ruffus

Posted July 11, 2006 - 04:13 PM


as long as you don't put it in a car\truck\bike that has a catalytic & or fuel injection, any regular 4 smoke won't be hurt, just smoke a bit. I wouldn't make it a habit though

  • ericinmichigan

Posted July 11, 2006 - 05:03 PM


You guys are all missing the real danger here - putting two-stroke pre-mixed gas into a four-stroke will make it run as an average of the two engines......in other words, it'll run as a THREE stroke. Geesh, how could all of you have missed out on this simple answer?? :ride:

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