New Vibration

[BrokenWheel]

So I did decide to take the bike to the mechanic for want of good weather or a place to work. After a test ride, the tech came back with two things:

1) Possible front tire out of balance, but unable to verify with bead balanced tires. Not too sure on this, as the video I linked above pretty clearly shows something going on in the rear.

2) Overfilled with oil by ~0.75 qts. He's saying that being overfilled was causing oil to get picked up in rear cylinder, causing oil fouling and rough running. Drained excess oil and reports the bike is much smoother now. Does this sound reasonable to everyone here?

Now, at my last oil change, I did as posted here and drained both plugs, new filter, and +4 qts 20w50 VTwin specific oil. I never did bother to check levels after based on reports of general unreliability of a dipstick check. Best I can figure is that I didn't have the bike fully warmed before draining the oil, so I didn't get it all. Possibly also overfilled by PO, as I am pretty sure I got roughly 4 qts out. Strange thing to me is I had almost 600 miles since last oil change before the vibration/ rough running condition became noticeable.

Anyway, I'll pick it up tomorrow after work and report back.

[Shores]

If you didn’t change the oil filter, then there could be too much oil, but .75 too full is unlikely to do anything other than blow it out the rear valve cover vent into your carb or another area you have the hose running to. I alway use Ride On balancing gel at each tire change and do not use any weights.

[Chooch]

If you removed both drain plugs and added 4 quarts of oil you should have 4 quarts of oil in your engine. Forget the dipstick. To be absolutely sure it would be necessary to drain the oil and measure it. I won't be convinced that being 3/4 quart overfilled will cause a buzzing vibration at high speeds until you tell us that your bike is now back to normal. I do hope that your bike is fixed.

[Chooch]

So what is the result?

[BrokenWheel]

Haven't had a chance to get out on the interstate and back up around 85mph. However, the ride home from the shop at about 65 did feel somewhat smoother. The tech did say that in addition to taking out the 0.75qts oil, they also adjusted belt tension, but I forgot to ask how far out of spec it was.

I'm grabbing my lift this weekend and plan to see if the rear wheel shudder issue is actually fixed sometime next week. If that looks good I'll throw the saddle bags and windscreen back on and do a final follow up ride.

As always, thanks to everyone for the input.

[Duke]

All of my bikes shutter when idling in gear with the rear wheel off the ground. Not so much in first gear, but 2nd, 3rd, and up.
Think about momentum built up in the rear wheel and the differences through the gears to the heavy crank, with all of the back lash, (gears, shift dogs, splines, chain, and belt) you will get a shutter, unless the RPMs are up.

[BrokenWheel]

I hadn't thought about it that way honestly.

[BrokenWheel]

Just wanted to check in and give an update - sorry it'a been a minute, I've been in NM for work the last few weeks.

Anyway, back on the road again 2-up at 70-75mph with no noticeable vibrations. Still need to do a long-fast-solo trip down the interstate, but it will probably be another few weeks before that happens. So far so good though.

On a completely unrelated note, and admittedly I haven't searched it yet, but does anybody know if there is a springer front end that will hold the stock (wide) '06 front wheel? I can only recall seeing skinny set-ups.

Thanks, as always.