exhaust/jetting qestion

gsxrninja250 · September 4th, 2011, 04:12 PM

Hey guys,

I wanted to know. If I put on a slip on exhaust. Put a k&n airfilter in it and removed the snorkle would I have to rejet the carbs?
Or can i get away with shimming?

Thanks.

alex.s · September 4th, 2011, 06:19 PM

you should get a full pipe and remove the airbox and replace it with pod filters, then rejet it

DerTeufel · September 4th, 2011, 06:36 PM

Quote:

Originally Posted by gsxrninja250

Hey guys,

I wanted to know. If I put on a slip on exhaust. Put a k&n airfilter in it and removed the snorkle would I have to rejet the carbs?
Or can i get away with shimming?

Thanks.

You can get away with shimming, but it won't be perfect. You'd be better served by rejetting.

gsxrninja250 · September 4th, 2011, 06:42 PM

Quote:

Originally Posted by alex.s

you should get a full pipe and remove the airbox and replace it with pod filters, then rejet it

I was thinking about it but then I've heard its really hard to jet it correctly after that. And does removing the air box really make that much of a difference?

alex.s · September 4th, 2011, 08:21 PM

airbox delete helps... its not a ton of work to jet http://www.factorypro.com/tech_tunin...m_engines.html

gsxrninja250 · September 4th, 2011, 09:20 PM

Quote:

Originally Posted by alex.s

airbox delete helps... its not a ton of work to jet http://www.factorypro.com/tech_tunin...m_engines.html

How much does the air box delete help?

alex.s · September 4th, 2011, 10:26 PM

it helps this much:

greatwhiteninja · September 5th, 2011, 07:41 AM

Quote:

Originally Posted by alex.s

you should get a full pipe and remove the airbox and replace it with pod filters, then rejet it

+1

Skippii · September 5th, 2011, 09:11 AM

I mean no disrespect, but I've never seen a forum where so many people want to spend hundreds of dollars on a new exhaust, and then desperately want to avoid spending $5 on new jets. It really baffles me.

greatwhiteninja · September 5th, 2011, 09:19 AM

i think its more the technical aspect involved with jetting for most as oppsoed to exhaust which seems to most who have never done it to just unbolt the old and put the new on..which jetting is easy, its just a little time consuming pulling the panels off to get to the carb. on a side note, removing the airbox and doing pod filters makes changing jets quite easy, all i need to remove is the side panels under the seat and the seat itself to pull my carbs out

Skippii · September 5th, 2011, 09:22 AM

Quote:

Originally Posted by greatwhiteninja

i think its more the technical aspect involved with jetting for most as oppsoed to exhaust which seems to most who have never done it to just unbolt the old and put the new on..loL!

Changing main jets isn't much more complicated than putting on an exhaust. At least on the pregens, haven't tried the new ones.
Almost all the performance gains come from rejetting, so I guess I just don't see the point of an exhaust without rejetting.

greatwhiteninja · September 5th, 2011, 09:30 AM

to someone who knows how to rejet this is true, but if youve never rejetted a bike before exhausts just seem way easier..lol! im with you though, changing jets is not difficult at all.

alex.s · September 5th, 2011, 10:17 AM

Quote:

Originally Posted by Skippii

Changing main jets isn't much more complicated than putting on an exhaust. At least on the pregens, haven't tried the new ones.
Almost all the performance gains come from rejetting, so I guess I just don't see the point of an exhaust without rejetting.

not if performance is measured by how quickly you go deaf...

choneofakind · September 5th, 2011, 11:15 AM

earplugs when you ride make riding so much more pleasant

gsxrninja250 · September 5th, 2011, 11:36 AM

Quote:

Originally Posted by Skippii

I mean no disrespect, but I've never seen a forum where so many people want to spend hundreds of dollars on a new exhaust, and then desperately want to avoid spending $5 on new jets. It really baffles me.

Because jets arnt 5 dollars. Jets are between 70 and 100 dollars depending on if you go dyno jett factoruy pro or area ps

Alex · September 5th, 2011, 11:41 AM

Jet kits are $70 - $100. Skippii's point has always been that the kits are a waste of money, as the individual jets are quite cheap if you know what you need.

DerTeufel · September 5th, 2011, 12:03 PM

Quote:

Originally Posted by Alex

Jet kits are $70 - $100. Skippii's point has always been that the kits are a waste of money, as the individual jets are quite cheap if you know what you need.

Correct. I prefer to use individual jets since they are quite a bit cheaper. I will stress that buying genuine Keihin or Mikuni jets is a must.

greatwhiteninja · September 5th, 2011, 01:12 PM

Quote:

Originally Posted by gsxrninja250

Because jets arnt 5 dollars. Jets are between 70 and 100 dollars depending on if you go dyno jett factoruy pro or area ps

Jetsrus.com they are actually right about $5 each lol, then you buy the pack of washers to shim the needles at radioshack for like $3 .

choneofakind · September 5th, 2011, 01:23 PM

but to answer the OP's question, if you want to get a slipon, and remove the snorkel, shimming should be sufficient.

but jetting really isnt that bad. The hard part is getting the carbs OFF the airbox and then getting them back on.

jetting really just takes patience, some mechanical aptitude, and lots of test-riding

alex.s · September 5th, 2011, 01:36 PM

Quote:

Originally Posted by choneofakind

The hard part is getting the carbs OFF the airbox and then getting them back on.

not if you don't have an airbox...

choneofakind · September 5th, 2011, 01:51 PM

Quote:

Originally Posted by alex.s

not if you don't have an airbox...

yes I can imagine it would be

but the OP only mentioned removing the snorkel and changing the filter

I'm actually considering the airbox delete, but every time i go to order parts I think about how long it will take me to hack it out and then rejet and get it all running to the same point I have it at now. Really all i want to do is ride my bike, not work on it. Besides, I already spent time tuning my carbs for my setup now. I don't want to do it all again...

alex.s · September 5th, 2011, 02:14 PM

i need to convince cuong to tune my fzr... i hear he's the master of carburetors. you might even call him the masterburetor...

September 4th, 2011, 04:12 PM	#1
gsxrninja250 ninjette.org member Name: chris Location: los angeles Join Date: Aug 2011 Motorcycle(s): none yet Posts: 118	exhaust/jetting qestion Hey guys, I wanted to know. If I put on a slip on exhaust. Put a k&n airfilter in it and removed the snorkle would I have to rejet the carbs? Or can i get away with shimming? Thanks.

September 4th, 2011, 06:19 PM	#2
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	you should get a full pipe and remove the airbox and replace it with pod filters, then rejet it __________________________________________________

September 4th, 2011, 08:21 PM	#5
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	airbox delete helps... its not a ton of work to jet http://www.factorypro.com/tech_tunin...m_engines.html __________________________________________________

September 4th, 2011, 10:26 PM	#7
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	it helps this much: __________________________________________________

September 5th, 2011, 09:11 AM	#9
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 mean no disrespect, but I've never seen a forum where so many people want to spend hundreds of dollars on a new exhaust, and then desperately want to avoid spending $5 on new jets. It really baffles me. __________________________________________________ "What a sweetheart."- ninja_sleeper to me

September 5th, 2011, 09:19 AM	#10
greatwhiteninja Ridin Dirty Name: Ed Location: Delaware Join Date: Jun 2011 Motorcycle(s): 2011 white se 250r , 2008 zx6R Posts: 921	i think its more the technical aspect involved with jetting for most as oppsoed to exhaust which seems to most who have never done it to just unbolt the old and put the new on..which jetting is easy, its just a little time consuming pulling the panels off to get to the carb. on a side note, removing the airbox and doing pod filters makes changing jets quite easy, all i need to remove is the side panels under the seat and the seat itself to pull my carbs out __________________________________________________ #1

September 5th, 2011, 09:30 AM	#12
greatwhiteninja Ridin Dirty Name: Ed Location: Delaware Join Date: Jun 2011 Motorcycle(s): 2011 white se 250r , 2008 zx6R Posts: 921	to someone who knows how to rejet this is true, but if youve never rejetted a bike before exhausts just seem way easier..lol! im with you though, changing jets is not difficult at all. __________________________________________________ #1

September 5th, 2011, 11:15 AM	#14
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	earplugs when you ride make riding so much more pleasant

September 5th, 2011, 11:41 AM	#16
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Jet kits are $70 - $100. Skippii's point has always been that the kits are a waste of money, as the individual jets are quite cheap if you know what you need. __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

September 5th, 2011, 01:23 PM	#19
choneofakind ninjette.org certified postwhore Name: . Location: . Join Date: Feb 2011 Motorcycle(s): . Posts: Too much. MOTM - Feb '13, Feb '14	but to answer the OP's question, if you want to get a slipon, and remove the snorkel, shimming should be sufficient. but jetting really isnt that bad. The hard part is getting the carbs OFF the airbox and then getting them back on. jetting really just takes patience, some mechanical aptitude, and lots of test-riding

September 5th, 2011, 02:14 PM	#22
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	i need to convince cuong to tune my fzr... i hear he's the master of carburetors. you might even call him the masterburetor... __________________________________________________

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Help with jetting and/or exhaust	2weelz	1986 - 2007 Ninja 250R Tech Talk	4	April 9th, 2014 03:46 AM
exhaust + jetting?	jmk420	2008 - 2012 Ninja 250R Tech Talk	35	June 23rd, 2013 08:33 PM
Full exhaust + airbox mod = how hi maintenance are the carbs/jetting?	675Raisinator	2008 - 2012 Ninja 250R Tech Talk	14	December 27th, 2011 12:05 PM
Dyno Charts with jetting and stock exhaust?	KURT	2008 - 2012 Ninja 250R Tech Talk	5	February 27th, 2011 10:03 AM
08 250R Dyno / after full exhaust + jetting	Order	Videos	20	January 19th, 2011 11:12 PM