

hello i am new here from pa and just returned from kentucky with a used 2006 brew force 750 kvfb model in snow camo. i really have not had a chance to really go over the unit but took it for a quick drive then parked it anyway 2 things i have noticed off the bat, 1- original owner has put an hmf exhaust on the atv it is a slip on but noticed when i rode it it is very throaty or boggy and extreemly loud not sure if i like it much but also not even sure if its properly tuned also not sure if any jets or anything like that was changed. when u rev it up it doesnt seem to respond very well i think due to the pipe any thoughts?
2- my other big question is u can hear the belt whine when in use and when u shut the unit off there is all kinds of noises comming from the belt location like some parts are moving, whining ???? is this normal i have only had a polaris in the past so this is all new to me any info is appreciated thanks