I recently had a new front and rear put on my blackline (commander ii's, 150 rear, 90 front) and now I have a strange vibration that happens at 20mph +- a couple mph, and only for that range of speed.

The vibration happens with clutch in, clutch out, in neutral, accelerating and decelerating. None of that makes any difference at all on the type or feel of the vibration. I saw another thread that was similar on another site from last year and didn't have any fix. The best way to describe it is like you're going over rumble strips, but much much more subtle. I can feel it in the bars, pegs, seat, etc. The bars do not wobble nor does the bike feel like it is wobbling at all and it tracks straight.

I've checked the rear wheel alignment and belt tension about 10 times and adjusted the belt looser/tighter and gone for test rides just to eliminate variables and it makes it no better or worse at any tension. The guy that mounted the tires balanced them both and has a very good reputation as one of the best. For the hell of it, I bought some ride-on and going to try that in the tires tomorrow when it comes in, but as of now, I'm at a loss.

The vibration doesn't feel like brakes and neither rotor appears warped when spinning the wheel and neither gets excessively hot and the brake pads have plenty of life. The wheel bearings appear to be fine and neither them nor the wheel spacers are hot to the touch after a ride.

The bike only has ~4500mi on it and the belt and pulley look brand new still. Before the tire change, it was smooth as butter.


edit: mechanic used stick on weights.

 

If you're going to put Ride On in your tires, take the weights off. Or maybe you already know/knew that.

 

Thanks, I planned on doing that to eliminate the wheel weights as a variable. As a bonus, I get a clean look on the wheel.

 

Could be bad tires.

If you had the shop install them, you would be able to have them exchanged out while you wait.

 

I'm hoping that's not the case since I bought the tires and then took them with the wheels to the guy to change out. Strange thing is that the tires feel 100x better than the stock dunlops that came off at every speed. Cornering is planted and road/tar snakes don't pull the bike around anymore. It almost feels like it has to be something else.

 

OEM tires are usually made of the cheapest materials to keep the manufacturing costs down.

 

Is the vibration from the front or rear? Its obvious that this happened after you installed new tires. So should be related. Id bring it back. Also, you are running spokes, so check tension there as well.

 

It's hard telling where it is coming from since I can feel it through the entire bike (from the bars to my tailbone). I just went over the spokes a few weeks ago (before tire change). I'm seeing a few other threads from a long while back to check that the belt isn't getting to close and rubbing on the mud guard. I'm going to check that later tonight. I've been running a 70t pulley in the rear for about 1000mi now with no vibration before the tire change. When I'm riding at all speeds, the belt is tracking all the way to the outside so I don't see this being the issue, but I guess I should see some wear on the plastic if it is making contact.

 

I have the exact same problem with my 14 Slim. Except that it happens between 40 and 45 MPH. I replaced the front tire and both bearings. I'm starting to think I have a broken belt in my rear tire, which I may replace soon. I also wouldn't rule out the drive belt, but the Harley shop said there was nothing wrong with it.

 

It didn't look like the belt ever touched the mudguard, but I trimmed it back anyway. Adjusted the belt and confirmed that my wheel alignment is dead nuts and took it for a ride.. Same thing.

I put it up on the Jack and both front and rear wheel have one tight spot that drag on the break pads.. When I say tight, I mean it takes my pinky finger to continue spinning the wheel along. All my bikes I've noticed drag on the pads when spinning free on the stand.. Anyone think that's what I'm possibly feeling? I'm at a loss for what else it could be. Motor mounts are tight, exhaust is tight everywhere. I'm about to just ride the damn thing and let it be.