Originally Posted by madmotorcyclist
I have an 09 model which I bought new. You mention not to throw away the tube that goes in the oil filter. I can not recall there ever having been such a tube in my bike, though I have always thought there should be. I change my oil every 3,000 miles and now have 38,000 miles on the bike. What effect does the lack of that tube have on my engine? I see the tube you mention shown in a parts blow up and assume I should order one.
Note the description of K part #16156-002. Piston-Assy, Valve, By-Pass.
The function of the part is to allow cold thick oil to By-Pass the filter media just temporarily, to fill the interior of the oil filter, the oil pipe, the hollow crankshaft, hollow camshafts and hollow transmission shafts and therefore Equalize the oil pressure on the Interior and Exterior of the oil filter. Thus preventing the cold thick oil from crushing the oil filter.
With-out the by-pass valve "pipe" (and its spring and plunger piston assy) inserted into the oil filter, the oil never is filtered. It just takes the path of least resistance, thru the open holes of the large rubber grommets.
I recommend that you order and install one at your earliest convenience.
To understand the oil filter system a little better, watch the video in this posting,