Exhaust/Shimming/FI question..

[jack_bm]

now its taken me a while to even think of this but say i got a dan moto exhaust for my FI ninja, how would i shim the needles in the carbs? because its a FI model they dont have carbs :S ( i think anyway lol ) would i then have to go out and buy a power comander or something?

[Joule]

it is actually confusing.
the mechanic that was well trained told me that there is an O2 sensor which will adjust fuel according to fuel intake.
Now after i removed snorkel,i don't know why i keep feeling that there has been no change in performance.

But anyways, if there is an o2 sensor, why would you need a power commander? just get exhaust and you are good to go?

Someone with experience help here please

[jack_bm]

Originally Posted by Joule

But anyways, if there is an o2 sensor, why would you need a power commander? just get exhaust and you are good to go?

Someone with experience help here please

surely it cant be that easy!! i hope it is though

[jack_bm]

Bump.

Someone must know?

If not i'll go to a bike shop and see what they say but would be good to get a view from someone who owns one

[csmith12]

I don't own a FI 250, but it's not going to be that much different than a bigger bike like my R6.

Install exhaust and the ECU will adjust as much as the installed map can. This is normally acceptable for most street riding. You may not need to but if you want every once of power out of the new engine/exhaust combo, you will have to get power commander and remap.

[jack_bm]

Originally Posted by csmith12

I don't own a FI 250, but it's not going to be that much different than a bigger bike like my R6.

Install exhaust and the ECU will adjust as much as the installed map can. This is normally acceptable for most street riding. You may not need to but if you want every once of power out of the new engine/exhaust combo, you will have to get power commander and remap.

Okay thats good to know, so say i got something like a dan moto the ECU will notice the difference and change it best to it can.. i'd only be getting a slip on so wont make to much of a difference i dont think anyway..

im not to worried about losing power as i'll eventually be getting a bigger sprocket and losing some top speed but gaining acceleration so i doubt i'll notice once thats done

[Skippii]

Well, if you have an o2 sensor installed on the stock exhaust and you replace that, it gets a bit more complicated. IIRC (that's a big if) the sensor is between the two cats on newgens. So slip on should be okay, but you'd need to modify and weld any aftermarked system for a full exhaust.
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[csmith12]

You should be good to go with a slip on with no other modification. Just ensure no leaks, it can cause improper readings from the 02 sensor.

[Sonofswin]

Alright, so basically the ecu adjusts various aspects of the bike (air/fuel ratio, ignition timing) according to the O2 sensor readings and a few other things (air intake temp, coolant temp, etc.) However, the stock ecu can only adjust so much, so if you make large changes in your intake/exhaust systems, it can't compensate enough.

Then, you'll need something like a power commander to maintain performance as well as to keep your bike in good condition. (Running it too lean all the time isn't going to be good for the engine.) The power commander simply adjusts the adjustments of the original ecu by overriding (disabling/replacing?) the O2 sensor and doing what you tell it to at a given throttle position and RPM. (Called Mapping) Thereby giving you the best performance for your set-up.

Pros: Even on a stock bike (Or one with a slightly modified intake/exhaust system) you'll get better performance and response with a smoother ride by using the stock map. (See the 1st post in the Jetting Database thread for a good explanation of why stock bike are as they are.)

Cons: They're expensive. AND, there aren't many maps out there, so you may have to pay someone to map your bike for you according to the system/conditions you ride in. (Also expensive.)

In conclusion: Do you need one? Probably not if you just add a slip-on. But I'd recommend you keep an eye on your plugs to see how your engine feels about it.

[jack_bm]

Originally Posted by Skippii

Well, if you have an o2 sensor installed on the stock exhaust and you replace that, it gets a bit more complicated. IIRC (that's a big if) the sensor is between the two cats on newgens. So slip on should be okay, but you'd need to modify and weld any aftermarked system for a full exhaust.
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oes the stock exhaust come with an 02 sensor installed? i have no idea lol

and IIRC? Whats that and cats? i thought we was talking about bikes

Sorry have noo idea what im doing with this

Originally Posted by csmith12

You should be good to go with a slip on with no other modification. Just ensure no leaks, it can cause improper readings from the 02 sensor.

Okay thanks for that is that what skipii means by welding an after market system to the full exhaust?

is that how you would have to make sure that its not leaking by welding it? or is there an easier way to make sure that it doesn't leak without having to weld it

[jack_bm]

Originally Posted by Sonofswin

Alright, so basically the ecu adjusts various aspects of the bike (air/fuel ratio, ignition timing) according to the O2 sensor readings and a few other things (air intake temp, coolant temp, etc.) However, the stock ecu can only adjust so much, so if you make large changes in your intake/exhaust systems, it can't compensate enough.

Then, you'll need something like a power commander to maintain performance as well as to keep your bike in good condition. (Running it too lean all the time isn't going to be good for the engine.) The power commander simply adjusts the adjustments of the original ecu by overriding (disabling/replacing?) the O2 sensor and doing what you tell it to at a given throttle position and RPM. (Called Mapping) Thereby giving you the best performance for your set-up.

Pros: Even on a stock bike (Or one with a slightly modified intake/exhaust system) you'll get better performance and response with a smoother ride by using the stock map. (See the 1st post in the Jetting Database thread for a good explanation of why stock bike are as they are.)

Cons: They're expensive. AND, there aren't many maps out there, so you may have to pay someone to map your bike for you according to the system/conditions you ride in. (Also expensive.)

In conclusion: Do you need one? Probably not if you just add a slip-on. But I'd recommend you keep an eye on your plugs to see how your engine feels about it.

What do you mean plugs? Spark plugs?

[Sonofswin]

Originally Posted by jack_bm

What do you mean plugs? Spark plugs?

Uh, yeah. Definitely not butt plugs!!

Anywho, your O2 sensor is way up on the main pipe right after where the two head pipes come together (Look at the Power Commander DIY on the wiki for a picture - or Google it) so don't worry about "leaks."

Installing a slip-on won't get you anywhere near that area of the exhaust. You just pull off your old silencer (The large muffler by the rear tire) and put on the slip-on using a short adapter pipe. I doubt you would even have to take your fairings off.

[greg737]

You need to ask yourself the "Why" question:

Why would Kawasaki engineering bother to include "self tuning" capabilities in the EX-250 ECU? Answer: they wouldn't.

The FI EX-250 as it rolls off the showroom floor isn't specifically designed to accomodate any performance mods.

Yes, it has an O2 sensor but it's a narrow band sensor not a wide band sensor. The narrow band sensor can only report lean vs. rich. It can't accurately tell the ECU how lean or how rich (beyond a tiny area right at 14.7 to 1 Air/Fuel ratio where it crosses over from reporting "lean" to reporting "rich").

Engineers and developers of automotive and motorcycle engines implement all sorts of little tricks of engine management within their ECU programing that allow them to tease out more information from a narrow band sensor than you would ever imagine they could, but if you go and make a big change in the engine's volumetric setup (how much air it flows) with things like aftermarket air filters and high flow exhausts, then the resulting need for more fuel at any given point in the ECU's Volumetric Efficiency Table (it's basic fueling "look-up" table) has to be addressed.

In a stock automotive or motorcycle FI setup the Narrow band O2 sensor (or more than one sensors, sometimes several in the higher-dollar cars these days) spends its time confirming the results of hard-programmed inputs (factory settings in the ECU's programming) rather than actually "tuning" the air/fuel ratios "on the fly" as the vehicle operates. The ECU package is factory tuned specifically to the hardware included on the engine in factory configuration. If the ECU is unable to confirm proper engine operation it will "throw a code" and light up the "check engine" type idiot light, telling you it needs the attention of a trained mechanic. In the worst cases of FI engine malfunctions the ECU will enter "limp-home" mode which reduces performance and keeps things safe until a professional can look it over (Aston Martin cars became notorious for this situation after the company implemented full electronic engine controls).

Based on what I know about FI (I'm about waist-deep in the DIY FI world) it seems that if you (the average motorcycle owner) want to do a quality upgrade of the performance of your factory FI bike you'd absolutely have to get the ECU remapped. That means paying somebody else for their expertise, knowledge, and the ability to implement it properly. All of which is necessary to do it right. So you have to do something like a Power Commander product that is properly configured for your bike and that takes into account the volumetric effects of the particular set of modifications you've made to it.

[jack_bm]

Originally Posted by Sonofswin

Uh, yeah. Definitely not butt plugs!!

Anywho, your O2 sensor is way up on the main pipe right after where the two head pipes come together (Look at the Power Commander DIY on the wiki for a picture - or Google it) so don't worry about "leaks."

Installing a slip-on won't get you anywhere near that area of the exhaust. You just pull off your old silencer (The large muffler by the rear tire) and put on the slip-on using a short adapter pipe. I doubt you would even have to take your fairings off.

Haha okay just making sure theres not some other plug that i just dont know about what would you look out for though? if i was to look at it i'd simply... look at it and think right, thats a plug

Originally Posted by greg737

The FI EX-250 as it rolls off the showroom floor isn't specifically designed to accomodate any performance mods.

Yes, it has an O2 sensor but it's a narrow band sensor not a wide band sensor. The narrow band sensor can only report lean vs. rich. It can't accurately tell the ECU how lean or how rich (beyond a tiny area right at 14.7 to 1 Air/Fuel ratio where it crosses over from reporting "lean" to reporting "rich").

But because its just a slip on it wouldnt really make any change to performance from what i gather, so can it be called a performance mod? i know it will slightly change it but not massivley which then makes me think... if it doesnt change the perfomance much wouldnt a narrow band sensor be able to do its... "Thing" and still be able to report what the mix is like where as if i had a full system it would be a big difference and you would need a wide band?

[greg737]

now its taken me a while to even think of this but say i got a dan moto exhaust for my FI ninja

I thought you were talking about a full exhaust. If you're only planning on a slip-on I'd say no problem because you're completely right in thinking that a slip-on is only an "exhaust note modifier" rather than a real change to the engine's volumetric characteristics.

So yes, go ahead with the slip-on modification and don't worry.

Or, if you're the type who can't help but worry just a little bit, here's the best spark plug inspection guide I've ever come across (it was produced by NGK back in 1977 but nothing has changed with regard to what the color/condition of a spark plug indicates about the operating conditions in the engine it's installed on).

http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html

[jack_bm]

Originally Posted by greg737

I thought you were talking about a full exhaust. If you're only planning on a slip-on I'd say no problem because you're completely right in thinking that a slip-on is only an "exhaust note modifier" rather than a real change to the engine's volumetric characteristics.

So yes, go ahead with the slip-on modification and don't worry.

Or, if you're the type who can't help but worry just a little bit, here's the best spark plug inspection guide I've ever come across (it was produced by NGK back in 1977 but nothing has changed with regard to what the color/condition of a spark plug indicates about the operating conditions in the engine it's installed on).

http://www.dansmc.com/Spark_Plugs/Sp...s_catalog.html

sorry that would probably be bad description on my part, yeah i dont see the point in spending £400+ on a full system then another load of money for a power commander.

Thanks for that though thats good to know it wont effect it, and thats a really good link! im always wanting to learn about the bikes because right now all iknow how to do it ride it, put petrol in and well... not a lot else so thanks again for everyone who helped

[Skippii]

Originally Posted by jack_bm

oes the stock exhaust come with an 02 sensor installed? i have no idea lol

and IIRC? Whats that and cats? i thought we was talking about bikes

Sorry have noo idea what im doing with this



Okay thanks for that is that what skipii means by welding an after market system to the full exhaust?

is that how you would have to make sure that its not leaking by welding it? or is there an easier way to make sure that it doesn't leak without having to weld it

IIRC = "If I Remember Correctly"

As far as the other questions...I think you might be getting in a bit over your head.

If you only want to make the bike louder, you shouldn't need to change anything else except the slip on. And no, you don't need to weld anything.

[jack_bm]

Originally Posted by Skippii

IIRC = "If I Remember Correctly"

As far as the other questions...I think you might be getting in a bit over your head.

If you only want to make the bike louder, you shouldn't need to change anything else except the slip on. And no, you don't need to weld anything.

Yeah i think im over thinking it but i get it now just put a slip on and happy days when i have a bit more money i've found someone who will be able to make me a custom exhaust pretty cheap so i might have a go with that and see how it goes