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Cranckcase filter for crf50 in the UK?

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Hi,

I've read lots of useful posts about how to put an aftermarket airfilter on my 50 i.e. one that straps right on to the carb, getting rid of the stock airbox mess. I would like to get hold of one of the K&N air filters to go on the end of the tube that come out of the cases (and would usually go into the air box).

Anybody know where I can get one in the U.K?

Also, if I can't get one for the weekend, are there any alternatives that are safe for the engine (I don't want to just leave the pipe hanging unfiltered etc).

Thanks a lot,

Mike

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You can just run a piece of vacuum or fuel line right from the crankcase breather nozzle on the upper rear portion of the engine, down the back, and let it hang down just below the swingarm bolt. All it does is equalize the pressure in the engine, it does not draw any air into the engine. The stock setup only serves to recirculate the air.

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You can just run a piece of vacuum or fuel line right from the crankcase breather nozzle on the upper rear portion of the engine, down the back, and let it hang down just below the swingarm bolt. All it does is equalize the pressure in the engine, it does not draw any air into the engine. The stock setup only serves to recirculate the air.

Uh...the title of this post says "crankcase filter" but I think his question is about the air filter.....I'm a little confused :cry:

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yo dirtbiker yes it does suck air. it also blows out air.

just like a speaker port.

ok theres a small catch box thats between the stock airfilter, you can cut a hole in the end of it and put the foam out of the stock airbox in the box. boom! intant filter.

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yo dirtbiker yes it does suck air. it also blows out air.

I stand corrected, thank you, fiveO

The crankcase breather does not draw in a significant amount of air, nor does it blow out a significant amount of air.

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In a perfectly running engine, the crankcase intake and exhaust would be about the same displacement at the engine, 49cc.

In reality, there is some blowby at the piston rings, decreasing some as RPM increases, making the exhaust slighty more than the intake.

Filter it, its cool.

Robert :cry:

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yo dirtbiker yes it does suck air. it also blows out air.

just like a speaker port.

ok theres a small catch box thats between the stock airfilter, you can cut a hole in the end of it and put the foam out of the stock airbox in the box. boom! intant filter.

Thats smart five0! Have you done that mod/does it work? Either way I'm gonna try it this weekend!

Thanks for all the replies!

Mike

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