rajnish can u also tell me wat is a sprts exhaust??

sports exhausts r nothing but free flow exhausts only.they come in diff. specs. as per the bike's requirements.

i mean sports exhaust for cars. my zen has a free flow exhaust. but there are also sports exhaust which make a kewl racing sound...wat are they??

the sports exhausts for cars come with exhaust tips which help in producing bass or try a different can shape.

ok... now expalin me the entire process.... pls rajnish. i want to make one...tell me from the starting to the end.

YES EVEN I WANNA KNOW RAJNISH

well not much idea of 4 st pipes.think it uses the dia of exhaust outlet compression and stroke leangth of the engine to design a pipe for it.indian companies just copy designs of foreign ones in case of cars.but any pipe should be tailor made for a bike.any ways a bigger jet and head polishing gives good results.followed by a bigger pilot jet and filter.

Four stroke performance tuning by Graham Bell is the book for tuning 4 st engines.plz go for it for full indeapth bout the four cycle engine.

DUDE YOU SURE KNOW A LOT ABOUT ALL THIS
KEEP UP THE GOOD WORK

HEY RAJNISH , ANY IDEA WHERE I CAN BUY THAT BOOK ??

u get get it from amazon.com

An tuned exhaust for a 2st is called an expansion chamber or tuned exhaust pipe as for the 4st it is called header. Making a free flow system for the 4st bike does not mean you just have to put a pipe with no ristrictions. You have to make the whole exhaust system free of any ristriction.

An exhaust system in a four stroke engine consists of:-

1. Exhaust Cam
This is a very vast subject so ill try to explain in brief right now and may be in detail later.
An exhaust cam is responsible for the duration and the hieght of the lift of the exhaust valve. The longer and higher the lift the faster the the exhaust gasses will flow out into the exhaust manifold. But a high lift cam needs to be designed very precisely.

This image will help you under stand better
You can see the four cycles. The green dots show the fresh mixture and the black dots show the exhausted mixture. Notice the cone like structure on the big red gear, it is called a lobe or Cam. You can also see the blue exhaust valve which is allowing the exhaust gas out.


2. Exhaust valve.
You can shave or grind the SEAT(The part of the valve where it touches the head of the cylinder) of the exhaust valve to give it a mirror finish. This will help in the free flow of the gasses. Againg it requires experienced hands.

3. Exhaust manifold.
Same as exhaust valve, Give it a mirror finish by shaving or grinding.

4. Exhaust pipe.
Basicaly to tune the bike to gain a particular Horse power at a particular rpm, you need to tune the length of the exhaust pipe(straight pipe). There are two types of exhaust pipes. Long pipe and short pipe.

Click on the link below for a detailed understanding.



If you need any clarifications. you are most welcome.

as per Four stroke performance tuning by Graham Bell-All cars/motorcycles have an individual header per cylinder... The rpm at which the power/torque is produced can be altered by the length and the diameter of the header pipe.The headers for each cylinder need not be of equal length and all of them empty into a collector.This will fool the engine into thinking that its emptying into open space and creates a pulse strong enough to suck out the exhaust gases and also suck in some of the fresh charge if there is a lot of valve overlapOn a stock engine with minimal valve overlap, a tuned exhaust would give power increase in the range of 5-10% .also what physics says as per my own understanding- Rule of thumb= If you want to go for peak end power with narrow band then Long tubes are the way to go.. if you are trying to tune it for mid range and fat torque curve then shorties are the way to go.. but it depends on the engine and its design.Also pardon my ignorence for 4 cycle engine lol.Also header is a part of the pipe not the pipe.

too much tech crap...... i cant understand..