Review on 🔥 Enhance Performance with K&N 63-1139S Performance Air Intake System,1 Pack by Justin Coatsworth

some assembly errors - if you use slotted nuts you need a pair of spring washers because at least one of the pins is too long and you need this to ensure a good seal put a washer under the slotted nut (( flat faces won't fit due to lack of clearance). Don't over-tighten the slotted nuts or you'll remove the plug (ask me how I know). K&N offered to replace the broken bits, but I just went to the local hardware store and bought what I needed for less than $10 - 4 nyloc nuts and a spare bolt less wide - there is very little gap between the body and nut for the wrench (and an open end is all that you get there), much harder to install than it needs to be, but one day you'll love it - gives the bike a deeper feel n sound and better throttle response. . I have an aftermarket tuner who allowed me to retune - your call.