Bike dangerously lean, Help!

[Bushman1]

Hey guys, sorry for the crappy intro here but I need your help. I have a 2010 with around 200 miles on the odo that I purchased for track only use. The engine mods so far are as follows: Akra slip-on, K&N Lunch box(R-0990), 112 mains from jetsRus, 2 washers under the stock needle and rerouted the crankcase vent hose to the air injection system(Kleen air mod or whatever its called). Anyways, I decided on this "set-up" after looking through various jetting charts and reading peoples positive results with my same modifications.

After her first track-day I get home, pull the plugs and they were crispy BRIGHT white!! I'm thinking no bueno so i pull the main jets and carefully drill some material out to see if that would help at all, well, fast forward after my next track day I pull the plugs again and they are STILL bright white. now remember this bike lives at 7K+ rpm's now so this really has me worried. Im not sure what my next step should be. Im almost starting to think the vacuum operated fuel petcock cant keep up with the fuel demand but then again maybe it just needs bigger jets(115's?). what do you guys think? help me out here. BTW, I live at sea level(south florida)

[Jiggles]

So the only mods are a slip on and the k&n? And you have 112 Keihns right? hmm

I have the k&n as well as a full exhaust. I'm currently running 115 Keihns and when at WOT my AFR is never over 14.0 However, I noticed today that when I am at partial throttle in the high revs my AFR is 15-16

The solution for you is probably just to WOT more

[alex.s]

if it's lean, add more gas

[Bushman1]

So I shouldnt try to bypass the fuel petcock valve or screw with the float height right? just throw in 115's or 120's?
I guess what I mean is, you guys dont think the float bowls are running out of fuel at WOT?

[Bushman1]

hey, what the hell? Jiggles, does the thing under your avatar say "faster than bushman1's ninjette??? WTF? lol... bring it!

[Jiggles]

Originally Posted by Bushman1

hey, what the hell? Jiggles, does the thing under your avatar say "faster than bushman1's ninjette??? WTF? lol... bring it!

It's already been abroughten

[Bushman1]

anyone else have any ideas?

[alex.s]

bigger main jet

[dino74]

Originally Posted by Bushman1

Im almost starting to think the vacuum operated fuel petcock cant keep up with the fuel demand but then again maybe it just needs bigger jets

It doesn't sound like the petcock is bad but its not hard to do a quick check. Pull the gas line from the carb and check the fuel filter. With the gas line unhooked from the carb, start the bike and see how much gas is coming out of the line.

Also, what size pilot jet are you using?

[Bushman1]

OEM pilot jet.

[kbryant]

Originally Posted by Bushman1

Hey guys, sorry for the crappy intro here but I need your help. I have a 2010 with around 200 miles on the odo that I purchased for track only use. The engine mods so far are as follows: Akra slip-on, K&N Lunch box(R-0990), 112 mains from jetsRus, 2 washers under the stock needle and rerouted the crankcase vent hose to the air injection system(Kleen air mod or whatever its called). Anyways, I decided on this "set-up" after looking through various jetting charts and reading peoples positive results with my same modifications.

After her first track-day I get home, pull the plugs and they were crispy BRIGHT white!! I'm thinking no bueno so i pull the main jets and carefully drill some material out to see if that would help at all, well, fast forward after my next track day I pull the plugs again and they are STILL bright white. now remember this bike lives at 7K+ rpm's now so this really has me worried. Im not sure what my next step should be. Im almost starting to think the vacuum operated fuel petcock cant keep up with the fuel demand but then again maybe it just needs bigger jets(115's?). what do you guys think? help me out here. BTW, I live at sea level(south florida)

Based on your mods, it is extremely doubtful that you would be running lean with 112 main jets, in these current hot/humid/sea level conditions. There is nothing wrong at all with a "like new" looking spark plug when run at WOT conditions. I would not be surprised if it was actually running rich (assuming it has the correct range plug and what gas you are running). Burning away all deposits and showing a clean plug is a good thing (obviously up to a point). The misconceptions are:

1. Where you are reading the plug. The "mixture ring" is located at the base of the insulator. This is "primarily" what you are concerned with to determine the mixture conditions. You've got to read the plug deep inside (for the most part). That's why as Tuners, we use a magnifying light scope to peer down to the base and inspect the mixture ring. There are a slew of other considerations, but this simply provides a base of understanding about reading plugs. But based on the info provided, can't imagine you're actually running lean. And actually, since you described no change when you "drilled out some material"; that also tells me you are actually running rich already.

2. How is the bike actually running/performing? Other than what you have seen at the spark plug, how does it perform?

Since now you don't actually know what size main jet you have (you drilled it), try going down to 104 or 106 and see how it runs. Sure it could be other things like the float level or petcock not keeping up. But those would be somewhat unusual and not the most common things to check without knowing how the bike is actually performing first.

Also, not sure why you would route the "rerouted the crankcase vent hose to the air injection system(Kleen air mod or whatever its called" (if I read your post correctly)? Honestly have not heard that one before. Plug the Kleen Air system and put a Crankcase Breather Filter on the nipple and/or hose from the engine.

[DaBlue1]

Just 200 miles? That engine ain't really broke in good yet, but aside from that, what octane gas are you using. A "white" plug can also be from overheating. The plug will also look very dry and the electrode may look eaten away.
A grayish looking plug is normal. According to your mods, you should be running in an optimal range. Any timing changes to your bike? Are you getting any detonation (knocking)?

[Motofool]

Welcome to the site, Bushman1 !!

Excuse me the question, but what type of plug and coolant are you using?

Any over-heating noticed during the first track day, any hard start, any lack of power, especially after some laps?
Those are the main symptoms of extreme lean mix.

Why "this bike lives at 7K+ rpm's"?

Only 200 miles is not enough to get some color on the plug.

http://www.dansmc.com/spark_plugs/sp...s_catalog.html

http://www.dansmc.com/carbs2.htm

[Bushman1]

Originally Posted by kbryant

Based on your mods, it is extremely doubtful that you would be running lean with 112 main jets, in these current hot/humid/sea level conditions. There is nothing wrong at all with a "like new" looking spark plug when run at WOT conditions. I would not be surprised if it was actually running rich (assuming it has the correct range plug and what gas you are running). Burning away all deposits and showing a clean plug is a good thing (obviously up to a point). The misconceptions are:

1. Where you are reading the plug. The "mixture ring" is located at the base of the insulator. This is "primarily" what you are concerned with to determine the mixture conditions. You've got to read the plug deep inside (for the most part). That's why as Tuners, we use a magnifying light scope to peer down to the base and inspect the mixture ring. There are a slew of other considerations, but this simply provides a base of understanding about reading plugs. But based on the info provided, can't imagine you're actually running lean. And actually, since you described no change when you "drilled out some material"; that also tells me you are actually running rich already.

2. How is the bike actually running/performing? Other than what you have seen at the spark plug, how does it perform?

Since now you don't actually know what size main jet you have (you drilled it), try going down to 104 or 106 and see how it runs. Sure it could be other things like the float level or petcock not keeping up. But those would be somewhat unusual and not the most common things to check without knowing how the bike is actually performing first.

Also, not sure why you would route the "rerouted the crankcase vent hose to the air injection system(Kleen air mod or whatever its called" (if I read your post correctly)? Honestly have not heard that one before. Plug the Kleen Air system and put a Crankcase Breather Filter on the nipple and/or hose from the engine.

Thank you for the detailed response. I would say the bike is running "ok". I say that because its only my second time riding it and i dont really have a gauge yet as to how it SHOULD run. What makes it worse is that my previous track bike was a 636 so to be honest it makes the little ninja feel a little... slow. But to be fair, the bike climbs through the rpm range without any stumbling or hesitation. again, its just a little slow, which I'm getting used to. I will say though, sometimes in mid corner if i let it drop below 7K rpm's there is a noticeable power loss.

Originally Posted by DaBlue1

Just 200 miles? That engine ain't really broke in good yet, but aside from that, what octane gas are you using. A "white" plug can also be from overheating. The plug will also look very dry and the electrode may look eaten away.
A grayish looking plug is normal. According to your mods, you should be running in an optimal range. Any timing changes to your bike? Are you getting any detonation (knocking)?

I'm running regular pump 87 octane and haven't noticed any knocking or pinging and I have not made any timing changes or messed with anything other than simple bolt-ons.

Originally Posted by Motofool

Welcome to the site, Bushman1 !!

Excuse me the question, but what type of plug and coolant are you using?

Any over-heating noticed during the first track day, any hard start, any lack of power, especially after some laps?
Those are the main symptoms of extreme lean mix.

Why "this bike lives at 7K+ rpm's"?

Only 200 miles is not enough to get some color on the plug.

http://www.dansmc.com/spark_plugs/sp...s_catalog.html

http://www.dansmc.com/carbs2.htm

The bike has OEM, NGK-CR8E's in it and im running water/water wetter. I havent noticed any overheating although sometimes after pitting in, the oil/water light comes on momentarily but it could just be from getting off the track after running wide open for 15-20 min and being a little warm. I say "the bike lives at 7K+ rpm's" because its track only and it usually stays in the upper rpm range.

[Bushman1]

Heres a video for you tuners of the bike going through the gears and accelerating. Let me know it sounds/seems right to you. Kinda hard to see the gauge sometimes and sorry about the shaking.

Link to original page on YouTube.

[250rr]

This is an example of dangerous lean. Hope this helps!