NOTE : Akhil appears to have typed out his reply a lot faster than i have this question
Hence, this edit..
Answers to the remaining questions would be appreciated however


Hmmm. I was under the impression that you didn't want to mess with the stock exhaust due to warranty concerns.
Any reason for the change in plans..?

An extremely valid doubt there OF sir. AFAIK the stock ECU on the One is capable of adjustments pertaining to ignition timing/fuel-air mixture ratios vis-a-vis altitude.
The backpressure in the pipes oughta to be dependant on altitude too i suppose and hence falls within the purview of the stock ECU. Clarifications to this end from Akhil, Ken da and yourself sought and awaited eagerly

Oh and what do the 'lambda readings' mean and quantify..?

Haha.. and I thought Maverick was the fast one

About the warranty, I haven't changed the exhausts or done anything. In any case, this was done on a separate Y pipe.

Lambda readings are the readings given to the ECU from the oxygen sensor I talked about in my writeup. There is a sensor plugged into the Y pipe which analyses the exhaust gas and sends back a signal to the ECU which then based on the input from the sensor, balances the air fuel mixture.

Now I need to measure the Lambda readings with and without a cat. Maybe OF sir can suggest a way to do this. I have an idea but not sure whether it will work.

Ahem. Ever seen me draw a 0.57 Colt Magnum from my holster..?
Its the typing speed that fails me


You actually purchased another Y pipe for your experiments..!!
Any plans of sticking to the cat-conless pipe for the One..?
You could switch over to the stock set once its time for a service

If it feels fine, then it should be fine. Engineering has always been about practicality and approximations. If possible, get the exhaust CO and HC level checked at idle; (1) when the engine is cold and (2) when anywhere above 90 degC. The CO and HC levels should drop as the engine heats up. If it is the other way round, then the ECU is possibly in conflict. Though I doubt of that happening. Could have occured with 2 strokes where back-pressure and scavenging are wedded together but 4 strokes are not 'that' susceptible to the pressure waves.

Measuring 'Lambda' is a difficult proposition. Even SIAM admits this. In any case, since it is a derived value, any variation in the elemental values could give strange results > like negative values for O2. Check this link here.

I think the cold/hot engine CO and HC measures would suffice as indicators of whether the ECU is friend or foe without the Cat-con.

Would love to know the idea though.
The altitude part is relevant to a certain extent. Actually, the 'oxygen' thing is more complex. The ECU meters the amount of fuel to be released when you demand it with the throttle. And the excess oxygen escaping with the exhaust gases help determine whether the mixture needs to be enriched or leaned, on a real-time basis, many times a sec (though this sampling rate depends upon the processing capacity of the chip inside - 32 bit etc etc). Too little fuel and you loose on the contributory cooling from the fuel's enthalpy of vaporization. Too much and you loose power due to incomplete combustion. The thing is that amongst from some twenty odd parameters the ECU uses (rpm, crank position, throttle position etc), the lambda value is one of the 'criticals'. Mess it up and you mess up not just performance but also the performing metallurgy of the engine (its all a game of heat in and out - everywhere).

OF: The link you mentioned was very helpful..I was thinking of a very simple method of measuring the lambda readings.

Since the o2 sensor returns an electrical signal to the ECU, can we not measure the signal and compare it to a signal from an o2 sensor of a bike with a cat con? Of course, controlling all the variables for this exercise between the two bikes is tough, if not impossible. That and the accuracy/calibration of the two readings were creating some doubts.

Your thoughts?

Pretty relevant as a method and typical of an engineer.

The point that occurred to me here is what in heaven do we do with the data so generated? Okay, we get a value 'x' for a stock bike and we get 'x-y' or 'x+y' for the one without the cat-con, with 'y' being the 'cat-con factor'.. Then what?? How do we deduce whether the 'new' value is not creating problems - short or long term - in the engine. After all thats what we are aiming for.

Am I being too simplistic or are we really chasing a red-herring? The shop manual does not talk of absolute value ranges for any parameter whatsoever- just the typical Japanese 'digital' checks - go or no go. Not much of a help in experimentation.

Looked up similar give-take on a few R1 forums. Nothing concrete. just that people have done a lot of mileage with the cat-cons out and the engines are going fine. I guess that should do for us...at least for the moment.

One suggestion though: pledge to hug a tree or adopt a whale NOW to preempt the sanctimonious green brigade from baying for your blood.

Edit: Just went through the SIAM link closely. See this statement "There is an oxygen sensor mounted upstream of the catalytic converter, meaning it is closer to the engine than the converter is. This sensor tells the engine computer how much oxygen is in the exhaust. The engine computer can increase or decrease the amount of oxygen in the exhaust by adjusting the air-to-fuel ratio. This control scheme allows the engine computer to make sure that the engine is running at close to the stoichiometric point, and also to make sure that there is enough oxygen in the exhaust to allow the oxidization catalyst to burn the unburned hydrocarbons and CO."
Upstream means once the gases flow past the Oxy-sensor, there is no further interaction between the ECU and the exhaust gases. The absence of restriction (as with the cat-con) increases the flow rate not by increasing the flow volume (which is defined by the engine swept volume) but by increasing the flow velocity (remember Q=AV from fluid mechanics). So flow at a higher velocity will need to be sampled quicker as there would be no momentary 'pooling' of the gases close to the cat-con. The element constituents of the gases and their respective ratios should not change. So, in short, there should be no appreciable difference in the lambda count.

Your thoughts on this??

One of our fatal trappings

Engineering studied effectively scars one for life. Don't know if it's positive or negative The same is applicable if not studied effectively as well


OF, the data generated would be a baseline to work with. I'm sure the very same exercise will be carried out by either the sensor manufacturer or the ECU manufacturer, in order to calibrate their respective component with the other. There must a base value which tells us if the engine is running at/close to the stoichiometric point or not. I tried to find an approximate value for this but wasn't quite successful.

In any case, I measured the voltage from the signal and on a cold engine and warm.

The readings spiked all over the place. The lowest I got was .46 V and the highest was .74 V.

Now to find how to co-relate this data to the engine running lean or rich.

Which is why I've played it safe by mentioning the spare Y pipe

In any case, I am a man of extremities, having a highly polluting superbike, and on the other hand, booked an electric car!

It might just balance out, you think?
Again, I'm not quite sure on the frequency of lambda readings being sent to the ECU. I'm trying to find out the manufacturer of the sensor, but even then, there are chances that they will not part with the information I need.

Parallely, I'm trying to run the same experiment on an R1 which has the cat con intact.

Your thoughts about my thoughts?

My Thoughts on your thoughts

I like that.

Agreed about the base-value. If one can get that somehow, then the red-herring turns out to be real and tasty. The cold engine readings would not be of much use I guess as the sensor needs to heat up before it actually performs. The CO values could reliably indicate lean or rich and so could the exhaust gas temperature.

The comparison route between with and without cat-con R1's could ferret out some answers though.

And you are not alone with spiking values. Check this text from wiki about lambda sensors

"The zirconium dioxide, or zirconia, lambda sensor is based on a solid-state electrochemical fuel cell called the Nernst cell. Its two electrodes provide an output voltage corresponding to the quantity of oxygen in the exhaust relative to that in the atmosphere. An output voltage of 0.2 V (200 mV) DC represents a lean mixture. That is one where the amount of oxygen entering the cylinder is sufficient to fully oxidize the carbon monoxide (CO), produced in burning the air and fuel, into carbon dioxide (CO2). A reading of 0.8 V (800 mV) DC represents a rich mixture, one which is high in unburned fuel and low in remaining oxygen. The ideal point is 0.45 V (450 mV) DC; this is where the quantities of air and fuel are in the optimum ratio, called the stoichiometric point, and the exhaust output mainly consists of fully oxidized CO2.

(bold mine)The voltage produced by the sensor is so nonlinear with respect to oxygen concentration that it is impractical for the engine control unit (ECU) to measure intermediate values - it merely registers "lean" or "rich", and periodically adjusts the fuel/air mixture to keep the output of the sensor alternating between these two states. The time period chosen by the ECU to monitor the sensor and adjust the fuel/air mixture creates an inevitable delay, which makes this system less responsive than one using a linear sensor (see below). The shorter the time period, the higher the so-called "cross count" [1] and the more responsive the system.

The zirconia sensor is of the 'narrow band' type, referring to the narrow range of fuel/air ratios to which it responds." (link here)

And I have a feeling that the 1 uses this type of narrow band sensor. The lambda sensor actually has very little use in high rpm operations and that is where most of the 1's are destined or expected to exist. Very few would ride a 1 at 90 kph in top.
The dilema remains......even for the makersHmmmm. I think the electric car lies just somewhere between the tree and the whale. Will do. You are safe...till your next indiscretion with the environment.

Another useful link here

OF: You could have posted that a few hours sooner, thereby saving me those few hours

Useful links, and your input is terrific as usual. Looks like my experiment went down the drain

All in the pursuit of knowledge..

Of what use is a new-born??

The experiment was a prompt...and thats more than useful. Its the tangents that help us reap the most benefits. Lets keep up such 'pursuits of knowledge'.

Cleaing and Washing K&N air Filter.

Thanks Rossiter. Next time around in Delhi, buzz me and we can probably get around to cleaning up my Cat Con too.

In the meanwhile, let us clean up the K&N filter that has accumulated filth over the past 3000 kms.

To open the filter, please refer to the post here:


Tools required will be the same. Over and above that, you will need to have the K&N filter cleaning Kit.

1.Once you got the dirty filter in your hands... here is a photo of the dirty filter and the detergent spray from the cleaning kit.


2.Liberally spray the detergent all over the filter and let it soak for a good 10 minutes. Make sure that it is not "too" long that the detergent starts to dry up on the filter:


3.Thoroughly wash the filter with a clean cold water mild spray, directed from the clean side to the dirty side of the filter.



4.Let the air filter dry naturally. Do not heat the filter to dry faster. Make sure the filter is completely dry. This normally takes a good couple of hours in peak summer.

5.Take the Oil Filter Oil pack from the kit.


6.And spray the oil liberally on the filter till all of the white filter paper appears pink.


Some filter oil packs may come in tubes. You have to do the same.

7.Re-install the filter as shown in the link posted at the beginning of the post.

Turn the ignition key and thumb the starter. Rev the throttle and hear for the change in breathing. She breathes easier.

Go for a ride!

Photos Courtesy: Old Fox and Ken Cool!

Have all the Super Bikes been parked? No update, no new DIY lessons since very very long.

@mash: Yes, this thread has gone dormant.

I'll be contributing a few things here soon.

In the meantime, hope Ken and the others have something up their sleeve(s)

Please reply masters

I have some questions on servicing issues:
1.) What amount exactly incurs on the service of these superbikes ???If done at our own and if at the service center, both??
2.) Does it vary from bike to bike,like Busa,Gixxer,R1,ducati etc. etc??Not about cruisers
3.)What are the tyres cost?? after how many kms they need a change??

They are quite variable. You might find some answers here: http://www.xbhp.com/talkies/superbik...-way-life.html