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OIl leakage after tip over??

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Just want to know if this is normal or possible. I tipped my crf250R on a berm and the bike was basically wheels up but kept running for about 5-7 second before I could get it upright. The bike lost a considerable amount of oil through the airbox drain. My assumption is that the oil ran into the head while the bike was upside down and ran out of the valve cover vent and into the airbox. Does that sound plausable? The bike has never leaked oil before so I hope thats what happened.

Any feedback is greatly appreciated.

Thanks.

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Yes you are correct, tthe oil ran out of the valve cover breather that runs into the airbox, thus into the drain.

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same thing happend to me today, and actually oil got into my carb and i was blowing white smoke everywhere. Theres actually a kit you can buy that re-routes from the airbox.

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same thing happend to me today, and actually oil got into my carb and i was blowing white smoke everywhere. Theres actually a kit you can buy that re-routes from the airbox.

You don't even need the kit. Plug the airbox, ditch the entire tube assembly and bracket and run a single tube from your valve cover down. Next time you are at a national look close at the Honda factory bikes.

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You don't even need the kit. Plug the airbox, ditch the entire tube assembly and bracket and run a single tube from your valve cover down. Next time you are at a national look close at the Honda factory bikes.

Very true, but the air that goes into that tube needs to be filtered. A piston on the up stroke will pull a vacuum on that tube and possibly contaminate the engine with dirt. That's why it terminates into the filtered side of the air box.

Pro engines get torn down every race....it doesn't matter to them.

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Very true, but the air that goes into that tube needs to be filtered. A piston on the up stroke will pull a vacuum on that tube and possibly contaminate the engine with dirt. That's why it terminates into the filtered side of the air box.

Pro engines get torn down every race....it doesn't matter to them.

It terminates into the box after the filter. I have a friend who is tight with a Honda Factory mechanic who did this mod to his bike. I was assured there is not enough to suck up garbage. The breather tube is there for emmisions and terminates to the box AFTER the filter so that the vapors will be used again for combustion. Gravity- one end to collect drainage below and at the airbox to collect vapor. That's why I have seen a bike where the rider didn't realize it was detached and his intakes were destroyed.

We have been running our bikes like this as advised by the factory mechanics and the motors are clean. You can filter the end but in order to keep your airfilter dry of engine oil- PLUG the airbox!!!:applause:

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So, you've answered the question on this thread but let me get this straight. My bike was purchased used and had this 'kit' on it. The tube that ran into the air box was cut and just hangs around behind my suspension cylinder. It runs to a Y connection. After the Y, one end goes to the cylinder head and one end runs the whole way down under my bike. Should I remove this Y connection and run the tube from the cylinder head under the bike?

Does everyone have this Y? If so, then any 'vacuum' caused by the engine would pull air in from either of the two hoses, even the one under the bike?

Here is a pic:

The tube that hangs there above the boot does smoke when the bike is running hot. What causes this?

IMG_0022_2.jpg

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They must have got lazy. You can ditch the Y or T fitting and run a straight tube from the valve cover out. There were so many threads that talked about engine vaccum and when I first got the bike I put in-line filters on every hose with filter foam and oil in them to collect anything that would get sucked up. They never sucked anything up. Most guys shorten them just in case and zip tie them to the frame.

That catch tube is to appease the lawmakers. I have been running this mod for almost two seasons. The key is to take the bike down every season and clean everything. I will say that the problem I have is that dirt finds it's way past the carb cover that shields the throttle cables. I'm always cleaning that.

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