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I just installed new PR4's on my 2014, they were installed on my wheels and computer balanced at a shop. Usually new tires get rid of the 45 mph handlebar shake at deceleration. This time between 40 and 50 mph it is pretty violent very quickly at deceleration with hands off the bars. Even keeping the same speed around 45 it feels like it wants to shake if I have very little pressure on the bars.

NOW, wouldn't I feel a wheel out of balance at all speeds? I took it up to 90 mph and I didn't feel anything really weird like at the 45 mph range.

On a sidenote, they put the wheel weights on the edge of my wheel, farthest they can away from the center of the wheel. In the past the wheel weights were installed as close to center as possible (along that raised part that runs through the valve stem). Is wheel weight location that important? Both front and rear took 4 squares of weights (there, now you know how little I know...ounces right?).

I hate taking the tires off. Do I need to take it off and take it someplace else? I guess I'm looking for what a wheel out of balance acts like, as I've never had one before and don't know if this is it.

Thanks,
Don.

A tire out of balance feels like a paint shaker. Only happens above 60 mph, getting worse the faster you go.

Bring the bike back. You have some tire issue not related to balance.

Sounds like it might be the steering head bearings to me. I've never seen an out of balance tire get better with speed, but that's just me.

Out of balance usually gets worse with speed. However...there are times when harmonics plays a role and I would guess the out of balance condition is doing so, makimg the handlebar shake worse than normal.

Handle bar shake is a slight out of balance that is amplified through the natural frequency of the forks and steering head. It goes away at higher speeds because the system damps higher frequencies.

Another thing, the weight on the edge of the wheel could be on purpose or just laziness. On car wheels, they balance each side and put weights on the edge to balance both static (wheel hopping up and down) and dynamic (wheel trying to turn out of plane ot wobble) modes. I haven't heard of this on a motorcycle because most front wheels are narrow enough the dynamic mode doesn't have a large effect because of the short moment arm. Rear motorcycle wheels are stabilized through a very ridgid swing arm and dynamic mode vibration just gets locked out mechanically.

So, my suggestion is to record the weight attached to your wheel, remove it and match that (in location and weight) with a center rib weight or a couple pieces of sticky weight near center line and see if it gets better. If it gets worse, put the original back where it was and remove the center weights.

I also second the steering head bearing check afterward because a bit of friction also helps damp the steering assembly.

My take on it is that a good handling motorcycle before a tire change and a wobbler after the change isn't instantaneous steering head bearing failure.

I have had a good handing bike go into the garage for a tire change and come out with wobbles around 45 mph. The dealer checked the bead line to verify the bead was set evenly all the way around both sides of the front & rear tire. They checked tire pressure, the balance, then they checked rim run-out. After not finding any problems they contacted the tire manufacturer. With no argument, no fight and no blood letting the tire company agreed to replace the front tire. They did at no cost. My motorcycle returned to a good handling bike immediately.

Good luck hunting down the root cause!

Yep. A bike that has no wobble that gets wobble during a tire change needs to have everything loosened, bounced, and re-torqued. My wobble disappeared as fast as it appeared.

Agree with comments above, you might want to get that tire rechecked. You might jack the front tire up in the air and spin it by hand. I look for tires to track true and evenly.

bill lumberg wrote: ↑Sat Jul 28, 2018 7:36 pm Yep. A bike that has no wobble that gets wobble during a tire change needs to have everything loosened, bounced, and re-torqued. My wobble disappeared as fast as it appeared.

Definitely do this before anything else. Most people don't and it can make a difference.

Thank you for all of the quick responses. I took the wheels into the shop with new tires, so that means taking taking the wheels off again on my own. I bought the tires from Rocky Mountain ATV, so I don't have a shop backing me up with their own experiencce if the tire is bad.

I'll go with the quick and easy responses first. Loosen, bounce, and torque everything again. Then I'll try moving the wheel weights towards the center. I found it odd that both the front and the rear took the 4 weights at the same part of the wheel (almost opposite the valve stem). I thought shops usually moved the light part of the tire to the valve stem area so less weights are needed, but this was a Saturday morning and they had a lineup of tire changes oil changes, so I doubt I got the best effort.

Also, I torqued the steering head bearings last fall when I added the helibar risers, and did not have any issues before the tire change. My PR4's with 9800 miles rode better than these do.

Stupid question, (there are supposed to be no such things as stupid questions but experience has proven otherwise)....
I originally torqued the front tire with it elevated. when I loosen, bounce, and retorque, should I have the tire in the air or resting on the ground?

Torque is torque.

I would bounce the front end to the ground several times with everything hand tight, then torque the axle nut and pinch bolts. But careful not to roll the bike off the center stand.

More to point. I torque with the tire on the ground.

Ok thanks.
I've done many FJR tire changes. Never had this problem before so trying to eliminate any possible human error.

What does an out of balance tire feel like? Bouncy, bouncy, bouncy. Like a pogo stick.

Magnitude of bounce depends on speed (harmonics of wheel speed and suspension settings). The bouncy trait can be dangerous and unbearable at one speed, and completely disappear at a different speed.

THERE ARE NO STUPID QUESTIONS, but there are morons and assholes who say, "That's a stupid question."

Deagle - I disagree. No bouncy feeling.
An out of balance tire is a "paint-shaker" feeling. Instead of being smooth up to FJR nominal, you may start getting a vibration that starts at 70-90 (depending on how much out you are) and gets worse the faster you go. If you stay below the throttle threshold it won't shake so much. I threw a weight one time...and until I got it taken care of, that's what it was like.

I've got a static balancer if you want to bring it over and we can check it.

I have had similar experience - lost a balance weight once and it felt like the front end was attached to a paint shaker when I hit 70.

Deagle10 wrote: ↑Sat Jul 28, 2018 10:05 pm Ok thanks.
I've done many FJR tire changes. Never had this problem before so trying to eliminate any possible human error.

My local Cycle Gear will match online prices and mount and balance my tires for free. The deal is only partially as good as it sounds.

Their tire balancer is off. It will recommend the correct amount of weight, but it gets misplaced by about 30 - 60 radial degrees. The end result (for a front tire) is a handlebar shake that only starts at about 75 mph and stops about 90 mph. I have a friend with a static balancer, so I tell C/G to just tape the correct amount of weight where they think it will go, and I bring it to my buddy with the static balancer and we get it right.

C/G insist that their machine is not off, because my buddy and I are the only ones that complain. We say that the rest of their customers don't ride like we do and their (respectful) ignorance does not prove a theory. We prefer using the laws of physics to support our own theory. The manager says he might reach out to the equipment manufacturer - that was 6 months ago.

It's always something....

I believe that for the most part, the rim is what is out of balance, not the tire. It seems like from tire change to tire change, the amount of weight remains the same (maybe 1/4 oz difference) and the placement is also pretty close (within an inch or so either way). Curious as to what others think.

Looking forward to hearing the rest of the story.

I've had different tires vary a lot...

Hppants wrote: ↑Tue Jul 31, 2018 8:16 am It's always something....

I believe that for the most part, the rim is what is out of balance, not the tire. It seems like from tire change to tire change, the amount of weight remains the same (maybe 1/4 oz difference) and the placement is also pretty close (within an inch or so either way). Curious as to what others think.

This. I dismounted both my front and rear tires, and tested just the rim balance out of curiousity. You are correct, they were out a noticeable amount. I marked the heavy spot inside of the rim with a grease pencil. Instead of mounting the yellow dot opposite the valve, I mount it opposite the heavy spot. Since doing that, the amount of weight I need to the add seems to be reduced, it's rare I need to add more than half an ounce, sometimes, no weight! Or maybe I've frost bitten my noggin one to many times.

Its a great feeling when both tires are near perfectly balanced at speed. I guess tolerance for balance on manufacture of the wheels is quite lenient.

Oh one other thing. I had my local dealer mount my RS3's a few weeks ago. They are noticeably out of balance, not paint shaker territory, but well beyond what I'd leave them at. They DID balance them, or, at least, change the weights and valves (it's a good idea to change valves/innards occasionally) because I can see my weights are gone with the stickem remnants left on the rim. I'm gonna have to pull them and balance them myself.