midpipes

I have two complete FMF Megabomb headers and midpipes. One is Ti and one is Stainless Steel and both are made to fit the FE390/450 '09 - '12 Husabergs. Both are new and never installed. I did test fit the Ti one on my FS570 and decided that it would take too much fabrication to make it work...

I have noticed on more than one occasion hearing liquid percolating in my bike when I stop after a tight slow section. I am not dripping coolant out the overflow hose and have not needed to add any either. I removed the gas cap and really dont see the gas boiling so not sure whats up BUt dont...