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post #1 of (permalink) Old 08-08-2007, 02:28 PM Thread Starter
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Thumbs down Need Help: CR250R Smoke & Smell

I was running 44:1 ratio in my 99' cr250 with 93 oct, however I found it a little too smokey. I decided to try 50 to 1. Which worked awesome. I adjusted the clutch then the bike started to smoke when it wasn't running. Now I'm getting some oil out the top of the cylinder . This smoke is white, it smells terrible, not like regular burned oil, but I don't think the clutch is slipping. Any input?

Running snythetic Bel ray 2-stroke oil . 50:1
stock compression, new clutch and top end.

Thanks ahead of time. Ian
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post #2 of (permalink) Old 08-09-2007, 12:31 PM
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Angry 50 to 1 ??????

Sound like, (smells like? ), antifreeze burning ... methinks you may have an internal leak somewhere? ... exaserbated by your choosing to run your motor hotter!

Your recommended fuel / oil mixture is 32 to 1 of which most racers push it to 40 to 1 ... however 50 to 1 is in my opinion way to little oil!
In a nutshell ... More oil is better because it:

Improves ring seating and sealing
Reduces overall sliding friction on piston skirt, ring(s), and bearings
Lubricates the bottom end crank bearings more effectively.

Also, contrary to popular belief, additional oil does not adversely affect carburettor jetting, unless at extreme ends of the spectrum, ie. going from say 100:1 to 15:1

That said ... methinks you should find out what has been damaged by the lack of lubrication and deal with the fact that you ride a two smoke ... It leaks oil on your garage floor , it smokes AND IT DEVELOPS MORE POWER THAN A FOUR STROKE!

Last edited by Anthony; 08-10-2007 at 02:23 AM. Reason: Adnl. info added.
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