@yellowspunk - overcharge your tyre to about 40-45 psi, and then ask the mechanic to check for leaks. I just fixed a slow leak on my R15 rear tyre yesterday like that. The puncture could not be located at 30-33 psi.

Do this after getting the valve checked first.

Thanks , but i'm sorry for not letting this go , but could you explain why my inference was wrong , preferably in layman terms , if thats ok .

can it be put without removing the panel next to the tank?
can anyone pls share some pics

Not a problem to explain.

What layman understands:
150cc engine in FZ = 150 cc engine in R15 = same power, same torque, same characteristics.

What a person with technical knowledge understands:
150 cc engine in FZ = wide power band, good for city riding (since it's known as a city bike)
150 cc engine in R15 = narrower powerband, good for racing (since Yamaha sells it as such)

FZ engine: 2 valves, carburettor, air cooled, lower cost, designed for lower power, lower torque but at a lower speed.

R15 engine: 4 valves, fuel injection, water cooled, higher cost, designed for higher power and torque but at a higher engine speed.

Jargon:

Power: Techically, the rate of work done. But easier to understand is amount of energy generated per unit of time. The more you have, the faster you can go, for the same amount of weight and drag to be overcome. Measured in kilowatt, horse power or brake horse power, or PS (German).

Torque: The force with which the crankshaft turns. The more you have, the faster you can accelerate, for the same conditions. Measured in newton metre or kilogram metre or kilogram force metre. Torque can be multiplied or divided by gears.

Power band: Range of engine speeds between which the most useable power is available. Outside this range the engine response and acceleration can be slow. So this is infact an indication of the torque band of the engine. In the power band, torque is highest, therefore the best acceleration is possible.

2 valves: The engine cylinder head contains 2 valves - one each for the inlet and exhaust. Good for low to medium power outputs and medium speeds.

4 valves: 2 valves each for inlet and exhaust. Good for medium to high power outputs and medium to high speeds.

Gearing: In general, but not strictly, the multiplication of torque and reduction of speed. When a gear ratio is greater than 1 (in most gearboxes, with some exceptions), speed of the driven wheel is divided by the gear ration and torque is multiplied by the gear ratio.

Power output of an engine is dependent on the amount of air - fuel mixture it can burn. The amount that can be burnt in each cycle varies according to the displacement of the piston, or the CC of the engine. Since that is fixed, the only way to get more power is to increase the engine speed thereby increasing the amount of fuel burnt per unit of time. This is why the R15 engine makes more power than the FZ but at a higher speed.

Torque mutliplication is the basis of the gearbox. No engine has enough torque at very low engine speeds to start moving a stationary vehicle. This is why gears are used to multiply torque and permit the engine to run at a higher speed where greater power and torque are available. The wheel speed is reduced thanks to the high gear ratio. The idea is to find the ratio that most closely matches the engine powerband with the road speed and load condition.

I think I've covered the basics but I may have missed something.

Dude...you forgot the bore and stroke point. the bore and stroke of these two bikes is also different which plays and important part on the power and torque curves that these bikes produce on the graph.

Bore: Diameter of the piston

Stroke: The distance the piston moves up and down.

Displacement (not engine capacity, as is usally mistaken) = volume of the cylinder formed by the moving piston.

The bore and stroke do influence the power characteristics of an engine for the same displacement but for small differences, as in the 150 cc category, their influence is little. Since no small Indian bike has the bore:stroke ratio of a super sports or super bike, this is more or less irrelevant.

However, their influence is very much visible in larger engines, even in India (Bullet, etc.) but that's another discussion.

thanks bro will do. i checked the valve too @ the service centre they said no leaks ! will do it now with 40psi.

thanks to both u guys , i knew these basics , but what i didn't know was about the valves . so thanks for the clarification .

yes it can be....pics attached

FZ Vs R15

Is it a good idea exchanging my Fz for R15?? ideas and comments plz

the R 15 is a more complete machine than the fz...depends on the deal ur getting and the requirements that u have....

^^ +1 on that .

thanx k2cool_87
is there sufficient gap between the crash guard and the shocks? will they touch when u turn the bike?

nope dude...this is a crash guard from yamaha it self so no such prblms...they have taken care of all that...

ok..so it can be fitted without any probs..
but yamaha doesnt hav crash guard for fz here in tvm..