It doesn't work, since as soon as a closed loop system goes open loop it will be running a predefined program to determine the amount of fuel to inject. Thus if this amount is rich for your normal air filter it will be lean for a high flow filter. More air, same amount of fuel. Thus remapping is required.

If the logic is to run the engine RICHER at WOT, i do not see any reason for the system to run lean.
Even if the Fuel injector has a restriction on its max mass flow rate, in port fuel injection systems, there is virtually 2 full revolutions of the crank available to dump the required fuel. So it is hardly impossible for a well designed Fuel injection system to not be able to meet the requirements.

It is not as simplistic as it is made to sound. Though Joel is the right person to clarify this issue, here is my understanding on the subject:

Modern bikes are designed with a number of design compromises built into them which include but are not limited to noise restriction, ever tightening emission norms, ever increasing demand for reliability and efficiency, etc, etc.

Keeping these compromises in mind, the basic air box designed in a production bike is designed as a part of the complete combustion system.
Changing the air filter will on its own will not get you a dramatic increase in performance. In fact, in many cases it can have a negative effect by leading to changes in the character of the power band by dropping power in certain range and gaining some in certain range.

In a highly tuned engine where airflow is restricted due to a ‘designed for street’ air box, changing to high flow air filter is a necessity to eliminate the bottleneck. However, it is a given that the library of fuel maps for the bike will need to be modified to take into consideration the changes made in the engine.

Now, getting down to the issue of the injector nozzle and its flow capacity. The flow capacity of an injector nozzle for most production bikes is good enough to handle at least 20% to 30% increase in power. It is a mistaken belief that Air Fuel Ratio is determined by the flow capacity of the injector nozzle. The Air Fuel Ratio is determined by what is called ‘pulse width’ i.e. the correct length of time that the injector must spray fuel. This pulse width is normally in milliseconds duration. Therefore, to alter the Air Fuel Ratio the pulse width will be increased or decreased a few milliseconds as required.

Joel, please correct me if I am wrong out here.

Read this.

Joel is the correct person to answer the myth/queries.

guys do u think that the fi tech will take over the market??? just give this a thought 83k for a zma and 110k for a yamaha r15!! around 25k more!!
the r15 is 150 cc 18 bhp but acclerates faster and top speed more than the 223 cc 18 bhp zma!!! it almost matches up with the p220!!! so is it worth spending so much money of 85k on a zma???

Now here you are comparing 2 bikes with entirely different layouts and purpose. R15 has a 4-valve, Liquid cooled engine whereas ZMR has a 2-valve, Oil cooled engine; R15 is much Lighter than ZMR (Approx 40 Kgs); R15 is meant for track days whereas ZMR is meant to be a tourer.

Now, as far as spending money is concerned, it should depend upon the purpose.

In the coming years you will find more and more use for FI in all kinds of bikes. With ever tightening emission norms and ever increasing demand for better mileage there is no other way to go but FI. To a certain extent it will be totally irrelevant as to which type of bike it is, stricter rules and regulations for emissions will dictate the use FI.

I think mates we are deviating from the topic.

FI definitely have an edge over the carburetor in most of the times. I am not even 1/100,000 knowledgeable as people like Joel to name a few, but my understanding still says that Fuel Injection works on the basic principle of pre-defined AFR. So as to say, That if the AFR for a particular bike at 900m ASL is x:1, then the fuel injection would try to maintain it say the same irrespective of the ASL. "How" is what I can not give an explanation on, as this is 10 times par my domain but talking about the practicality of it, I guess any or all of my mates who have ridden their FI bikes to various Altitude levels would be the best people to comment on.

As the FI system ensures the recommended AFR goes to the combustion chamber, hence it maintains a cleaner emission. In simple words, it would regulate the fuel flow in accordance to the Air (Oxygen) level, which would in turn ensure that the emission is under control.

I personally for that matter would prefer to get a FI bike than to buy a carb one. I have experienced the difference after I bought the FI cars post 2000. talking about the serviciability, well, its just a matter of time. Something that is easily serviced today might have faced all sorts of concerns few years back at their time of introduction.

I can recall, as told to me by my elders that when Vespa Scooter was introduced to the Indian Market (in the Era of Lambrettas and Vijay Supers) few people went ahead criticizing the scooter talking about the stability as - its engine is on one side, hence it will fall.

Every technology, every evolution brings along few negatives. But those negatives are worth overlooking. These days we all are trying to get a bike with Disc brakes, owing to the wonderful brakes, but lets not forget that a Disc Brake is not that easily serviceable as compared to a drum brake, gives more resistance to the wheel under free movement. So did we ever went up to Yamaha and Bajaj to get us a P220 or an R15 with drum set up both in front and rear.

Just think about it.

All Cheers

dcs

i agree with this point of urs dcs! i feel buying a carb one is waste of money!!! where u r getting a better performance in the fi tech for a little more price!!!

kk dude i am talking about the zma r the carb one!!! not the zmr!!! by the way ur post was quite informative! didn no zmr had only 2 valves!!

how does a four valve and a 2 valve engine affect the bikes performance???? wat do the valves do???

guys as discussed before,we know its not simple to fit FI unit in a Carburated Machine but would like to know is it possible to fit a carb in a Fuel injected one.?

EDIT+ is it possible to fit Karizma's carb to a zmr (i know am asking a dumb question and nobody gonna do that But still wanna know the possibilities of Fi to carb conversion technique

its like selecting an old fashioned girl when u r getting a hot babe!! cmon dude y do u want to convert it to carb???? ull have to open up the whole engine to do that!!

hey mate don't forget that Old is gold

nyk am a happy user of carbureted machine and i realize the fact that no one will go for such modes just wanna know whether such modes can be done that's all

It is possible, however, it is not a simple solution of removing the fuel injection system and bolting on the carb. Depending upon the how intricate the FI system is, the whole fuel system may need to be pulled out including the fuel pump, the ignition maps, the sensors, the throttle cables, etc, etc. In other words, you need to weigh the benefits vis-a-vis the amount of work and trouble you will need to go through.

ok i would like to no more on the 2 valves and the 4 valves concept!!! the pulsar 135 is a 4 valve bike wat is so bettr in having a 4 valve than to have a 2 valve?????