How To Improve Performance of Karizma?

Kiruba · May 26, 2013

15kmpl is the mileage of an i-VTec Honda City. Dude some basic functionality gone wrong. Try cleaning the main stuffs like carb, use proper engine oil. But don't think of reboring. Whats your ODO?

jarpickle · May 27, 2013

rockstaraditya18 said:

Please re read your post before you click on the submit reply button, there are too many typos to understand what you are really trying to say.

Why are you trying to compete with a Pulsar 220?Why not just enjoy your bike.

Rejetting a carburettor will reduce your mileage.

If you already have ordered a K&N filter, I would suggest you use it.

Yes NGK is a company.Like I suggested try getting NGK platinum spark plugs and not Iridium ones.

Please read my entire post before replying.If I posted a link there it is for your benefit.If you choose not to read it because it is too long, it is your laziness.

uditgt · Jul 26, 2013

the modifications that i am mentioning are least expensive and which can improve your torque and bhp to a quite noticeable difference,
1- carburetor
carburetor allows to fuel to pass through really small jets also seen as small screws with holes, you can get them replaced with larger one, this might cost you just few bucks out of your pocket including labour.
2- air intake+air filter
the air intake pipe is situated below the seat which is pathetic, you first of all open up your seat and air filter side panel of your bike ,permanently close the opening of air intake below your seat via anything your mechanic suggest and just get a stock replacement high performance air filter , but you air filter needs to breathe so make holes in your air filter box ,after this you will love the way you bike will sound. perform this modification after following with the 1st point bcoz amount of air flow will increase tremendously so if you don't replace your jets you will face lack of high end power which is easily noticeable and less throttle response at high rpm's.You can do this yourself.do not worry about the rains.
3- exhaust
get your CAT removed for sure, and remove the muffler or silencer with the cheapest aftermarket muffler because all are the same the only difference is in the chamber of mufflers which do not affect the performance of you bike. do not buy complete aftermarket exhaust for karizma its a complete waste of money.
Basic idea is getting a pipe installed as straight as possible with least possible bents.
Don't go into any high end mods on this bike complete waste of money and time.

Last of all things i don't like karizma's technology engine is non-responsive,faulty gearbox, it handles like a atlas bicycle with an engine or some home built bike from 1900's hate its chassis which has been same from past so many years no advancement even Hero Honda's cheaper models are more technologically advanced than karizma.And parts quality is as low as possible.

racerdabba · Aug 1, 2013

uditgt said:

the modifications that i am mentioning are least expensive and which can improve your torque and bhp to a quite noticeable difference,
1- carburetor
carburetor allows to fuel to pass through really small jets also seen as small screws with holes, you can get them replaced with larger one, this might cost you just few bucks out of your pocket including labour.
2- air intake+air filter
the air intake pipe is situated below the seat which is pathetic, you first of all open up your seat and air filter side panel of your bike ,permanently close the opening of air intake below your seat via anything your mechanic suggest and just get a stock replacement high performance air filter , but you air filter needs to breathe so make holes in your air filter box ,after this you will love the way you bike will sound. perform this modification after following with the 1st point bcoz amount of air flow will increase tremendously so if you don't replace your jets you will face lack of high end power which is easily noticeable and less throttle response at high rpm's.You can do this yourself.do not worry about the rains.
3- exhaust
get your CAT removed for sure, and remove the muffler or silencer with the cheapest aftermarket muffler because all are the same the only difference is in the chamber of mufflers which do not affect the performance of you bike. do not buy complete aftermarket exhaust for karizma its a complete waste of money.
Basic idea is getting a pipe installed as straight as possible with least possible bents.
Don't go into any high end mods on this bike complete waste of money and time.

Last of all things i don't like karizma's technology engine is non-responsive,faulty gearbox, it handles like a atlas bicycle with an engine or some home built bike from 1900's hate its chassis which has been same from past so many years no advancement even Hero Honda's cheaper models are more technologically advanced than karizma. And parts quality is as low as possible.

All the points stated by you have flaws.
Do u really think all exhaust cans are same, and high end exhausts are a waste of money? You are very mistaken. The way gases escape is a very important part of engine efficiency. Exhaust is a very critical part WRT flow dynamics and velocity.
Please do not touch the exhaust if you don't know what you are doing.
A straight pipe will affect back pressure and low end torque. An aftermarket cheapo muffler harms more than good.

uditgt · Aug 3, 2013

P3T3R said:

racerdabba said:

I still don't understand what part you did not understand about my post
firstly its all about inexpensive but most effective means most effective mods that can be done at home or any where. Cheap after market muffler starts from rs400 to 4000 or more foolish amount for karizma only differenece originating between these mufflers is mentioned below for suppressing noise and pollutants.
As advice to fellow readers cheap after market mufflers do not harm your engine at all but are really effective and get your cat con removed for visible perfomance change.
Back pressure: What is it ?¿. One of the most misunderstood concepts in exhaust theory is back pressure. People talk about it with no real understanding of what it is and what it's consequences are. I'm sure you believe in the phrase "Engines need back pressure" when discussing exhaust upgrades. Sadly, that phrase is completely inaccurate and a wholly misguided notion.

All mufflers impede the flow of exhaust gas to some extent. The more that the muffler / exhaust system impedes the total flow of the engine, the more reversion and "back pressure" is generated. This not only lowers the potential for power, but also fuel efficiency.
The majority of the sound pressure produced by the engine is emanated out of the vehicle using the same piping used by the silent exhaust gases absorbed by a series of passages and chambers lined with roving fiberglass insulation and/or resonating chambers harmonically tuned to cause destructive interference wherein opposite sound waves cancel each other. (Glasspack - glasspack is a type of automobile muffler in which the exhaust gas passes straight through the center of the muffler. The basic design consists of one smaller tube centered inside of a larger outer tube that is enlarged or swollen in the middle. The gap between the swollen part of the larger outer tube and the smaller diameter center tube is packed full of fiberglass. )
Performance oriented mufflers and exhaust systems thus strive to minimize back pressure by employing numerous technologies and methods to attenuate the sound.

Exhaust Design and Back Pressure

1. Some basic exhaust theory
Your exhaust system is designed to evacuate gases from the combustion chamber quickly and efficiently. Exhaust gases are not produced in a smooth stream; exhaust gases originate in pulses. A 4 cylinder motor will have 4 distinct pulses per complete engine cycle, a 6 cylinder has 6 pules and so on. The more pulses that are produced, the more continuous the exhaust flow. Back pressure can be loosely defined as the resistance to positive flow - in this case, the resistance to positive flow of the exhaust stream.
2. Back pressure and velocity
Many people mistakenly believe that wider pipes are more effective at clearing the combustion chamber than narrower pipes. It's not hard to see how this idea would be appealing - as wider pipes have the capability to flow more than narrower pipes. However, this omits the concept of exhaust VELOCITY. Here is an analogy...a garden hose without a spray nozzle on it. If you let the water just run unrestricted out of the hose it flows at a rather slow rate. However, if you take your finger and cover part of the opening, the water will spray out at a much much faster rate.
The astute exhaust designer knows that you must balance flow capacity with velocity. You want the exhaust gases to exit the chamber and speed along at the highest velocity possible - you want a FAST exhaust stream. If you have two exhaust pulses of equal volume, one in a 2" pipe and one in a 3" pipe, the pulse in the 2" pipe will be travelling considerably FASTER than the pulse in the 3" pipe. While it is true that the narrower the pipe, the higher the velocity of the exiting gases, you also want make sure the pipe is wide enough so that there is as little back pressure as possible while maintaining suitable exhaust gas velocity.

Back pressure in it's most extreme form can lead to reversion of the exhaust stream - that is to say the exhaust flows backwards, which is not good. The trick is to have a pipe that that is as narrow as possible while having as close to zero back pressure as possible at the RPM range you want your power band to be located at. Exhaust pipe diameters are best suited to a particular RPM range. A smaller pipe diameter will produce higher exhaust velocities at a lower RPM but create unacceptably high amounts of back pressure at high rpm. Thus if your power band is located 2-3000 RPM you'd want a narrower pipe than if your power band is located at 8-9000RPM.
Many engineers try to work around the RPM specific nature of pipe diameters by using set-ups that are capable of creating a similar effect as a change in pipe diameter on the fly. The most advanced is Ferrari's which consists of two exhaust paths after the header - at low RPM only one path is open to maintain exhaust velocity, but as RPM climbs and exhaust volume increases, the second path is opened to curb back pressure - since there is greater exhaust volume there is no loss in flow velocity. BMW and Nissan use a simpler and less effective method - there is a single exhaust path to the muffler; the muffler has two paths; one path is closed at low RPM but both are open at high RPM.
3. The Manifolds
The manifold is an assembly designed to collect the exhaust gas from the engine cylinders into exhaust pipes, (either one or two with Morgans). Manifolds are often made of cast iron in stock cars. Many have material-saving design features to use the least metal, to occupy the least space necessary, and/or have the lowest production cost. These restrictions often result in a design that is cost effective but that does not do the most efficient job of venting the gases from the engine.
Inefficiencies generally occur due to the nature of the combustion engine and its cylinders. Since cylinders fire at different times, exhaust leaves them at different times, and pressure waves from gas emerging from one cylinder might not be completely vacated through the exhaust system when another comes. This creates back pressure and restriction in the engine's exhaust system and limits the engine's true performance possibilities.
A header (aka branch manifolds or extractors) is a manifold specifically designed for performance. Engineers create a manifold without regard to weight or cost but instead for optimal flow of the exhaust gases. These designs can result in more efficient scavenging of the exhaust from the cylinders. Headers are generally circular steel or stainless tubing with bends and folds calculated to make the paths from each cylinder's exhaust port to the common outlet all equal length, and joined at narrow angles to encourage pressure waves to flow through the outlet, and not backwards towards the other cylinders. In a set of tuned headers the pipe lengths are carefully calculated to enhance exhaust flow in a particular engine revolutions per minute range and married to the firing sequence.
3. How did the myth about back pressure and big pipes come to be?
I believe it is/was a misunderstanding of what is going on with the exhaust stream as pipe diameters change. For instance, someone with a Honda Civic decides he's going to upgrade his exhaust with a 3" diameter piping. Once it's installed the owner notices that he seems to have lost a good bit of power throughout the power band. He makes the connections in the following manner: "My wider exhaust eliminated all back pressure but I lost power, therefore the motor must need some back pressure in order to make power." What he did not realize is that he killed off all his flow velocity by using such a ridiculously wide pipe. It would have been possible for him to achieve close to zero back pressure with a much narrower pipe - in that way he would not have lost all his flow velocity.
4. Why is exhaust velocity so important?
The faster an exhaust pulse moves, the better it can scavenge out all of the spent gasses during valve overlap. The guiding principles of exhaust pulse scavenging are a bit beyond the scope of this article but the general idea is a fast moving pulse creates a low pressure area behind it. This low pressure area acts as a vacuum and draws along the air behind it. A similar example would be a vehicle travelling at a high rate of speed on a dusty road. There is a low pressure area immediately behind the moving vehicle - dust particles get sucked into this low pressure area causing it to collect on the back of the vehicle. This effect is most noticeable on vans and hatchbacks which tend to create large trailing low pressure areas - giving rise to the numerous "wash me please" messages written in the thickly collected dust on the rear doors.
Many designers will increase the length of the exhaust, trying to achieve a faster flow and a larger area of low pressure. Short pipes create a smaller low pressure area.

How To Improve Performance of Karizma?

Kiruba

V4

jarpickle

V10

uditgt

V2

racerdabba

V6

uditgt

V2