So just rode to work this morning bike felt a but sluggish , but I put this down to the cold morning,  on arriving I notice white smoke coming from front exhaist pipe and the pipe itself was black and almost looks burnt,

Can someone tell me what this, is it just the crap on the exhause burning off 

Just to edit the smoke was coming from the black patch on exhaust external and not out the end 

Road crap burning off.