Knocking noise when rear wheel is turning
So I noticed this low frequency knocking sound last year cruising @ 25 mph. That was near the end of the season. Now that it's closing in on riding season I'm looking to fix it. Bike has just over 4000 miles.
So far I've put the bike on the rear stand and confirmed that it makes the noise still. Even got a friend to validate my high NVH sensitive self that I'm not feeling/hearing things. It is very hard to pinpoint where it is coming from. Even with a stethescope.
So it's there I've done the following:
1. Changed gears with it. Frequency goes up the higher the gear. So it's not an engine noise.
2. Removed the rear caliper. Did nothing
3. Removed the front sprocket and ran it in all gears. No noise.
4. Put it in 1st gear and went from loose chain to tight chain. No change.
5. Checked run out on the axle. .002, within .010 spec.
6. Looked at and felt rear bearings. Seemed ok. Putting the wheel and drive flange on the axle and spinning it by hand showed no noise or rough spots.
7. Chain and sprockets look OK and I've been pretty consistent on lubing and tensioning the chain. But I'm kind of a newbie so maybe I goofed something up.
Rather than go drop money on a new chain/sprockets is there anything else I can check? I've thought of taking the chain off and rolling it down the hill next to the house to see if I get the noise. But then I have to push it back up the hill and I'm not sure that would tell me anymore than I already know.
Thanks in advance.
2004 Yamaha FJR 1300 ABS
2010 VW GTI DSG
1976 Datsun 280Z Turbo