over the weekend a friend borrowed my 690SM with akrapovic full system to do his test and we put the baffles back in. The other day i took them out again and now it pops and bangs its head off. It sounds pretty good tbh but i dont understand why it has suddenly started. It did do it a bit before but nowhere near as much.
The only thing i could think of is that when we were pulling out the baffles we disturbed the pipework so air is getting in and igniting in the silencer. But i checked everything and it all seems airtight. It is quite badly coked which suggests it running rich i believe, I did supposedly have the map updated recently but he didnt seem to understand the concept of an 'akrapovic map' so god knows whats on it.
Any ideas what would cause the sudden change and is it likely to do any damage?