Carb Jetting, dont know if there's a real problem?

Trainsk8 · November 8th, 2010, 09:21 PM

Let me fill in on some background first. I have a 2010 Kawasaki Ninja 250r and i've had it for the past six or seven months and have done some good mods done to it. Some cosmetic, but i've also taken the whole airbox out and replaced it with a K&N R-0990 air filter, Area P 12" carbon fiber full exhaust system, along with a factory pro jet kit. I've been messing around with the carb settings, testing out different configurations over the past few weeks whenever i had the time to do so. But now i have it pretty good. running a 115 main jet, needle clip position set good, and just installed a #40 pilot jet to see what it would do. it runs great now, but after the bigger pilot jet was installed the choke doesn't really work. the cable's connected right and there's nothing wrong with the mechanism, so i'm guessing the #40 pilot jet messed up the idle or something and the choke doesn't affect it. the only thing it does is bump up the idle rpm +300. i haven't touched the fuel mixture screws yet so maybe if i did something to those, it would change. Also, when i blip the throttle it doesn't seem to run rich or lean just drops right down to the set idle speed.
Any answers or suggestions, ideas, ect. would be greatly appreciated, i'm still fairly new to this and just learning as i go, thank you.

kkim · November 9th, 2010, 12:09 AM

http://faq.ninja250.org/wiki/How_to_...e_your_jetting

http://www.ninjette.org/forums/showthread.php?t=10208

Nemesis · November 9th, 2010, 10:26 AM

Just FYI - When I first got the Factory Pro kit, I ran a 112 main jet and what felt like the bike was running good was actually in fact doing more harm than good. I discovered after logging in 10+ hrs on the dyno that I was running way too rich in the higher RPMs. It felt good but the dyno showed I was losing power in the higher RPMs.

115 is way too high IMO. You're in a higher altitude so a 92 may be better for you. Then elevate the needle using washers if it's too lean. Then adjust the fuel mixture screws.

If you have access to a dyno shop I strongly suggest you do that. Hopefully they won't charge much.

Just my .02

Trainsk8 · November 9th, 2010, 01:37 PM

i did try to put the stock #98 main jet back a while back, and it ran horribly. The air filter i have on mine gets great intake and even when i rode with a 112 for a while it seemed ok then the other night i switched to #115 and it seems to run perfectly. the only thing i dont understand is that the choke doesn't seem to be working right, it only brings the bike up to 2500 rpm when on. any idea why that might be?

kkim · November 9th, 2010, 01:41 PM

Quote:

Originally Posted by Trainsk8

i did try to put the stock #98 main jet back a while back, and it ran horribly. The air filter i have on mine gets great intake...

define "horribly".

which air filter (make/model) are you using?

Trainsk8 · November 9th, 2010, 02:29 PM

well basically the bike acted as if it was getting barely any fuel, i cant remember exactly what happened but it didn't seem right so i went back to the 112 and changed again recently and it works perfectly. the air filter is a K&N R-0990. it's a universal filter and just happens to fit on the old airboxes inlet tubes pretty well. its a big oval filter, google it and u can find photos
oh yeah haha, never mind about the choke not working, i just tried it again and it works normal, it must have been really cold this morning and i was in a rush. i hate being blonde! lol, but thank you for the help though i'm thankful that this site is up so people can help each other out. now i just have to get my throttle to not stick

Nemesis · November 11th, 2010, 12:50 PM

Not #98 but #92.

Where do you have the needle clip positioned? A/F mixture screws <--mess with them.

112/115 is still too high. Again, what feels good does not necessarily mean it's the proper setting you should be running at.

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November 8th, 2010, 09:21 PM	#1
Trainsk8 ninjette.org member Name: Brady Location: Marysville, OH Join Date: Aug 2010 Motorcycle(s): 2010 Kawasaki Ninja 250R Posts: 28	Carb Jetting, dont know if there's a real problem? Let me fill in on some background first. I have a 2010 Kawasaki Ninja 250r and i've had it for the past six or seven months and have done some good mods done to it. Some cosmetic, but i've also taken the whole airbox out and replaced it with a K&N R-0990 air filter, Area P 12" carbon fiber full exhaust system, along with a factory pro jet kit. I've been messing around with the carb settings, testing out different configurations over the past few weeks whenever i had the time to do so. But now i have it pretty good. running a 115 main jet, needle clip position set good, and just installed a #40 pilot jet to see what it would do. it runs great now, but after the bigger pilot jet was installed the choke doesn't really work. the cable's connected right and there's nothing wrong with the mechanism, so i'm guessing the #40 pilot jet messed up the idle or something and the choke doesn't affect it. the only thing it does is bump up the idle rpm +300. i haven't touched the fuel mixture screws yet so maybe if i did something to those, it would change. Also, when i blip the throttle it doesn't seem to run rich or lean just drops right down to the set idle speed. Any answers or suggestions, ideas, ect. would be greatly appreciated, i'm still fairly new to this and just learning as i go, thank you.

November 9th, 2010, 12:09 AM	#2
kkim Join Date: Nov 2008 Posts: Too much.	http://faq.ninja250.org/wiki/How_to_...e_your_jetting http://www.ninjette.org/forums/showthread.php?t=10208

November 9th, 2010, 10:26 AM	#3
Nemesis CVMA #74 WSMC #750 Name: Nemesis Location: On the track Join Date: Oct 2009 Motorcycle(s): All of them Posts: A lot.	Just FYI - When I first got the Factory Pro kit, I ran a 112 main jet and what felt like the bike was running good was actually in fact doing more harm than good. I discovered after logging in 10+ hrs on the dyno that I was running way too rich in the higher RPMs. It felt good but the dyno showed I was losing power in the higher RPMs. 115 is way too high IMO. You're in a higher altitude so a 92 may be better for you. Then elevate the needle using washers if it's too lean. Then adjust the fuel mixture screws. If you have access to a dyno shop I strongly suggest you do that. Hopefully they won't charge much. Just my .02

November 9th, 2010, 01:37 PM	#4
Trainsk8 ninjette.org member Name: Brady Location: Marysville, OH Join Date: Aug 2010 Motorcycle(s): 2010 Kawasaki Ninja 250R Posts: 28	i did try to put the stock #98 main jet back a while back, and it ran horribly. The air filter i have on mine gets great intake and even when i rode with a 112 for a while it seemed ok then the other night i switched to #115 and it seems to run perfectly. the only thing i dont understand is that the choke doesn't seem to be working right, it only brings the bike up to 2500 rpm when on. any idea why that might be?

November 9th, 2010, 02:29 PM	#6
Trainsk8 ninjette.org member Name: Brady Location: Marysville, OH Join Date: Aug 2010 Motorcycle(s): 2010 Kawasaki Ninja 250R Posts: 28	well basically the bike acted as if it was getting barely any fuel, i cant remember exactly what happened but it didn't seem right so i went back to the 112 and changed again recently and it works perfectly. the air filter is a K&N R-0990. it's a universal filter and just happens to fit on the old airboxes inlet tubes pretty well. its a big oval filter, google it and u can find photos oh yeah haha, never mind about the choke not working, i just tried it again and it works normal, it must have been really cold this morning and i was in a rush. i hate being blonde! lol, but thank you for the help though i'm thankful that this site is up so people can help each other out. now i just have to get my throttle to not stick

November 11th, 2010, 12:50 PM	#7
Nemesis CVMA #74 WSMC #750 Name: Nemesis Location: On the track Join Date: Oct 2009 Motorcycle(s): All of them Posts: A lot.	Not #98 but #92. Where do you have the needle clip positioned? A/F mixture screws <--mess with them. 112/115 is still too high. Again, what feels good does not necessarily mean it's the proper setting you should be running at.