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'74 oil injection

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I'm in the early stages of restoring a 74' Yamaha mx125. Apparently this bike had oil injection with a oil tank behind one of the side plates. Is it possible to just "delete" this so called injection and mix the oil with the gas like a regular 2 stroke?

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Yes, many have done so on DT/MX's of all sizes. Be sure and cap off the injection point. I think I mixed 20:1 on mine, but with modern oil 32:1 should make her happy. You may need to adjust that or rejet to suit.

Edited by knudsen
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I would keep it myself.I run one on my bike and its so handy.If you take the pump off,make a plate to plug the hole.As far as the jetting goes,mix around 32:1 and check the plug after a short ride and see if its okay.If its golden brown,just leave it alone.If it is kinda white then swap the jets for a size bigger.One common miss conception about a two-stroke is that to much oil fouls the plug,its actually the opposite.If your plug is fouling a lot then use a little more oil in the mix.

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My whole thing on the oil system is if something goes wrong with it along the way there goes the motor... If I mix it in the gas I know for sure the oil is getting to the motor the whole time it's running

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True enough,I had one go on me when I was breaking in my rebuilt motor.The gasket let go and completely fried my motor.You should change the gasket and the seal if considering using it.It is so nice not to have to mix,especially when riding on the road.You have to keep an eye on it and make sure its pumping oil and the gasket doesn't go.I find I foul less plugs with the pump.

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