Why do Royal Enfield bikes make a noisy sound while other bikes don’t?
For your que, first understand the bore x stroke factor. You must be knowning what is an engine cylinder looks like. The diameter of the Cylinder is called BORE. The height is called STROKE. Now try to understand that if the Bore is more than Stroke than the cylinder will be broad and if vice-versa than it will be longer. If it is broad than the piston has to travel less distance resulting in higher higher frequency of ups and downs and ultimately making the engine high revving. more horsepower – less torque. (Eg. mostly superbikes with 12000–15000 rpm revving engines).
On the counterpart, if the Stroke is more than the Bore than the piston will have to travel more distance resulting in lower frequency of ups and downs ultimately making the engine low revving. less horsepower – more torque. (Eg mostly cruisers and standard bikes like Harleys and RE’s. Thats why you will find 8000 RPM max reading in RE tachometer).
RE Classic 500
Power (PS@rpm) 27.2 bhp @ 5250 rpm
Torque (Nm@rpm) 41.3 Nm @ 4000 rpm
Bore 84 mm x Stroke 90 mm
Honda CBR 650F
Power (PS@rpm) 85.2 bhp @ 11000 rpm
Torque (Nm@rpm) 62.9 Nm @ 8000 rpm
Bore 67 mm x Stroke 46 mm
Look at the bore x stroke .
And for the sound, RE’s exhaust system doesnt valve-out the gases in a linear equally distributed amount rather it creates a bulk of small gases particle.
