The exhaust system is not free flowing
If the new exhaust has beenon the bike for a week or two and it's gotten worse you best stop riding because the engine could be running too lean and burning the valves.
A ticking noise could also indicate that your new exhaust that you have fitted is leaking somewhere. I know from experience that IF an exhaust is leaking from where it bolts onto the manifold inlet, then this can cause a ticking sound. A loose spark plug can also cause a ticking sound.
Is the noise intermittent with a random sound level pitch? Or is it a constant level of noise matched by the RPM of the engine? Random could be inferior metal used in the construction of the muffler. As the pipe heats up, the metal expands and contracts in different sections of the pipe causing the metal to make ping sound. Constant could be exhaust leak, valve adjustment, worn cam journals, cam chain tensioner.
