For those who installed K&N aftermarket air filter

Bosgarage57 · March 14th, 2012, 03:44 PM

Im installing an K&N single airfilter right now, taking the old air box out, my question is, what did you guys do with the air breather that comes from the crank case and went into the airbox?

choneofakind · March 14th, 2012, 03:51 PM

http://faq.ninja250.org/wiki/What_do...e_vent_hose%3F

here's something I found that looks like it should work just fine when I was pricing out doing that to my bike. http://www.amazon.com/Uni-Filter-UP-...=1GJVBLRZ7DXB1

Bosgarage57 · March 14th, 2012, 05:32 PM

Thanks CH, you saved my butt again! I went to local autozone and picked up a cheap breather and some radiator hose. Works pretty great.

choneofakind · March 14th, 2012, 05:35 PM

WOOT!

having fun jetting yet?

Bosgarage57 · March 14th, 2012, 05:43 PM

lol didnt get it all back together tonight. I've played around with the jetting before becuase I have an area P on it, but it wont rev past 8k. I think its getting too much gas......not sure though. Im going to get it all buttoned up tomorrow and resync the carbs "just in case" then fun with the jetting.

choneofakind · March 14th, 2012, 05:52 PM

hmmm, won't rev past 8k, just installed a single pod filter, I'm guessing it's lean

seriously though, with that and a full area P, you should be expecting to be running either 110 or 112's most likely. Test 108, 110, and 112 mains. 105's aren't going to be enough.

Zaydoc · March 14th, 2012, 06:17 PM

Go to autozone and pickup a spectra breather filter. You can either drill the hole out with a 1/2" bit or buy an adapter.
Posted via Mobile Device

Skippii · March 16th, 2012, 10:25 AM

I just stuck a fuel filter on the end of the hose to keep dust from getting in the engine.
K&N pods are, IMHO, pretty much the only "performance mod" that actually makes a measurable difference.

Bosgarage57 · March 16th, 2012, 10:40 AM

Thanks skippii, what did you do with the battery? We were thinking of cutting the airbox to get the battery box off, it'll still bolt down. Is that what you did?

flynjay · March 16th, 2012, 11:16 AM

Quote:

Originally Posted by Bosgarage57

Im installing an K&N single airfilter right now, taking the old air box out, my question is, what did you guys do with the air breather that comes from the crank case and went into the airbox?

I went to the local hobby store and bought a carb filter for nitro cars.

Quote:

Originally Posted by Bosgarage57

Thanks skippii, what did you do with the battery? We were thinking of cutting the airbox to get the battery box off, it'll still bolt down. Is that what you did?

I cut the battery box off. I have the tool kit wedged in behind the battery to keep if from moving too much.

You are going to love installing the carbs now, soooo much room to work with!

CZroe · March 16th, 2012, 12:05 PM

After installing an aftermarket undertail, my battery box dangles from the bolts on top of the frame/under the seat. It doesn't have anything to do with the airbox so I'm having a hard time visualizing how it would interfere with K&N pods that occupy the space the airbox used to be in.

Edit: Well, my perspective *IS* coming from a current-gen. IGNORE ME!

Skippii · March 16th, 2012, 01:46 PM

I can't remember what I did. I removed the airbox by smashing it with a hammer into small pieces so I could remove it and the carbs easily.
Posted via Mobile Device

greg737 · March 16th, 2012, 02:20 PM

During my FI project I installed a K&N 0990 filter. That left the crankcase breather with nothing to connect to so I inserted a piece of tight-fitting tubing into it and routed it up to the back of the 0990 filter. I drilled a right-sized hole in the back of the filter and press fit the other end of the tubing into it.

So now my EX-250 crankcase breather functions like it did in the stock setup, and that means its opening is protected inside the air filter and when the bike is operating it is subjected to the slight negative pressure (suction) produced in the air filter.

About the airbox. I kept the battery holder part and the floor of the airbox. I liked that it could be bolted right back into the bike with plenty of room for the K&N filter to be removed easily. It's great to be able to keep the battery secured in its OEM position and the OEM toolkit still fits in its original position.

I used the frontside of the battery holder and the floor of the airbox to mount various components of my FI system.

lc86 · March 16th, 2012, 09:22 PM

Quote:

Originally Posted by Bosgarage57

lol didnt get it all back together tonight. I've played around with the jetting before becuase I have an area P on it, but it wont rev past 8k. I think its getting too much gas......not sure though. Im going to get it all buttoned up tomorrow and resync the carbs "just in case" then fun with the jetting.

If you look at this walkthrough for installing it http://www.kawiforums.com/ninja-250r...ir-filter.html the author writes that " Also I learned the hard way that you NEED to re-jet before you can really run without the air box. If you're going to rip out the factory air box make sure you have a jet kit (with jet sizes 110-115 or so). Otherwise the bike will run so lean you won't be able to rev past 5k or so. (Look on the bright side, changing jets is a cinch after that damned air box is gone!)"

I didn't have this problem when I installed mine because of the EFI kit

Quote:

here's something I found that looks like it should work just fine when I was pricing out doing that to my bike.

Thats the exact one I bought for mine, works perfect.

Quote:

I can't remember what I did. I removed the airbox by smashing it with a hammer into small pieces so I could remove it and the carbs easily.

I used a very big pair of dykes to help in my 'removal' of the airbox, once it was out I finished it off with a hammer...may it burn in hell.

Snake · March 17th, 2012, 09:59 AM

Quote:

Originally Posted by greg737

During my FI project I installed a K&N 0990 filter. That left the crankcase breather with nothing to connect to so I inserted a piece of tight-fitting tubing into it and routed it up to the back of the 0990 filter. I drilled a right-sized hole in the back of the filter and press fit the other end of the tubing into it.

So now my EX-250 crankcase breather functions like it did in the stock setup, and that means its opening is protected inside the air filter and when the bike is operating it is subjected to the slight negative pressure (suction) produced in the air filter.

About the airbox. I kept the battery holder part and the floor of the airbox. I liked that it could be bolted right back into the bike with plenty of room for the K&N filter to be removed easily. It's great to be able to keep the battery secured in its OEM position and the OEM toolkit still fits in its original position.

I used the frontside of the battery holder and the floor of the airbox to mount various components of my FI system.

Greg,
I love your idea of running the crankcase breather tube to the back of the filter.

March 14th, 2012, 03:44 PM	#1
Bosgarage57 ninjette.org sage Name: Luke Location: Sevierville, TN Join Date: May 2011 Motorcycle(s): 06 Buell Uly, 05 VStar 1100 Posts: 577	For those who installed K&N aftermarket air filter Im installing an K&N single airfilter right now, taking the old air box out, my question is, what did you guys do with the air breather that comes from the crank case and went into the airbox?

March 16th, 2012, 10:25 AM	#8
Skippii Milkshake Drinker Name: Skippii Location: Richmond, Va Join Date: Aug 2011 Motorcycle(s): 2007 Orange DRZ400-S, 2005 Ninja 250 & Custom Thundercunt Dirt Chopper Posts: A lot.	I just stuck a fuel filter on the end of the hose to keep dust from getting in the engine. K&N pods are, IMHO, pretty much the only "performance mod" that actually makes a measurable difference. __________________________________________________ "What a sweetheart."- ninja_sleeper to me

March 16th, 2012, 12:05 PM	#11
CZroe CPT Falcon Name: J.Emmett Turner Location: Newnan, GA Join Date: Apr 2009 Motorcycle(s): '08 CP Blue EX250J, '97 unpainted EX250F, 2nd '97 unpainted EX250F (no engine), '07 black EX250F Posts: A lot.	After installing an aftermarket undertail, my battery box dangles from the bolts on top of the frame/under the seat. It doesn't have anything to do with the airbox so I'm having a hard time visualizing how it would interfere with K&N pods that occupy the space the airbox used to be in. Edit: Well, my perspective IS coming from a current-gen. IGNORE ME! Last futzed with by CZroe; March 16th, 2012 at 08:21 PM.

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March 14th, 2012, 03:51 PM	#2
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	http://faq.ninja250.org/wiki/What_do...e_vent_hose%3F here's something I found that looks like it should work just fine when I was pricing out doing that to my bike. http://www.amazon.com/Uni-Filter-UP-...=1GJVBLRZ7DXB1

March 14th, 2012, 05:32 PM	#3
Bosgarage57 ninjette.org sage Name: Luke Location: Sevierville, TN Join Date: May 2011 Motorcycle(s): 06 Buell Uly, 05 VStar 1100 Posts: 577	Thanks CH, you saved my butt again! I went to local autozone and picked up a cheap breather and some radiator hose. Works pretty great.

March 14th, 2012, 05:35 PM	#4
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	WOOT! having fun jetting yet?

March 14th, 2012, 05:43 PM	#5
Bosgarage57 ninjette.org sage Name: Luke Location: Sevierville, TN Join Date: May 2011 Motorcycle(s): 06 Buell Uly, 05 VStar 1100 Posts: 577	lol didnt get it all back together tonight. I've played around with the jetting before becuase I have an area P on it, but it wont rev past 8k. I think its getting too much gas......not sure though. Im going to get it all buttoned up tomorrow and resync the carbs "just in case" then fun with the jetting.

March 14th, 2012, 05:52 PM	#6
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	hmmm, won't rev past 8k, just installed a single pod filter, I'm guessing it's lean seriously though, with that and a full area P, you should be expecting to be running either 110 or 112's most likely. Test 108, 110, and 112 mains. 105's aren't going to be enough.

March 14th, 2012, 06:17 PM	#7
Zaydoc ninjette.org member Name: Jason Location: Fort Drum, NY Join Date: Aug 2011 Motorcycle(s): 2004 Ninja 250R Posts: 46	Go to autozone and pickup a spectra breather filter. You can either drill the hole out with a 1/2" bit or buy an adapter. Posted via Mobile Device

March 16th, 2012, 10:40 AM	#9
Bosgarage57 ninjette.org sage Name: Luke Location: Sevierville, TN Join Date: May 2011 Motorcycle(s): 06 Buell Uly, 05 VStar 1100 Posts: 577	Thanks skippii, what did you do with the battery? We were thinking of cutting the airbox to get the battery box off, it'll still bolt down. Is that what you did?

March 16th, 2012, 01:46 PM	#12
Skippii Milkshake Drinker Name: Skippii Location: Richmond, Va Join Date: Aug 2011 Motorcycle(s): 2007 Orange DRZ400-S, 2005 Ninja 250 & Custom Thundercunt Dirt Chopper Posts: A lot.	I can't remember what I did. I removed the airbox by smashing it with a hammer into small pieces so I could remove it and the carbs easily. Posted via Mobile Device

March 16th, 2012, 02:20 PM	#13
greg737 - Name: - Location: - Join Date: May 2009 Motorcycle(s): - Posts: A lot.	During my FI project I installed a K&N 0990 filter. That left the crankcase breather with nothing to connect to so I inserted a piece of tight-fitting tubing into it and routed it up to the back of the 0990 filter. I drilled a right-sized hole in the back of the filter and press fit the other end of the tubing into it. So now my EX-250 crankcase breather functions like it did in the stock setup, and that means its opening is protected inside the air filter and when the bike is operating it is subjected to the slight negative pressure (suction) produced in the air filter. About the airbox. I kept the battery holder part and the floor of the airbox. I liked that it could be bolted right back into the bike with plenty of room for the K&N filter to be removed easily. It's great to be able to keep the battery secured in its OEM position and the OEM toolkit still fits in its original position. I used the frontside of the battery holder and the floor of the airbox to mount various components of my FI system.