Modern Vespa

Yes, if you have a lathe and the knowhow

When I bought my 2015 BV, I noticed a gallop when doing 10-50MPH. Not a wobble, an up and down bounce that wasn't noticeable above 50MPH. So I had 2 choices. Bad tire/balance or suspension. Taking the easy way, I put dyna beads in the front tire and they made no change. After breaking the bead and vacuuming out the dyna beads, I rebalanced the tire on my Harbor Freight balancer. No change. So I had the wheel spin balanced. That decreased the gallop about 80%.
So I've come to the conclusion that the best way to balance MY tires is to have them spin balanced.
While I'm waiting for parts for the bearing replacement, I've been putting in extra effort to my commuter(2014) bike. So I figured, good time to make a way to spin balance the rear tire.

Now it's time to praise the people at CycleGear. Not only do they spin balance tires for free. Alex at the Orange Park location, allowed me to measure their machine to make what was necessary to do my wheel

Nice! Glad you got it sorted!

Do you think this is a problem we will run into when replacing my rear tire?

Well, who knows - but it is certainly true that everyone who owns a BV350 for very long replaces the rear tire periodically. Most of us have no way to spin balance the rear tire and wheel. Mine was static balanced when replaced. Appeared to work fine.

I had my rear tyre replaced a month ago and queried the balancing issue with my dealer. He said he hadn't rebalanced it and claimed that it made no difference in his opinion and experience.

I then did 1000 miles on a quick tour of Holland and Germany and I have to say that it did not feel any different to the original tyre. The wheel itself still has the factory fitted lead balancing weights on the rim in their original locations.

Alan

There's no CycleGear near you but I'll static balance it for you.

breakinwind,
Did you check the runout of the wheel?

I'm a machinist. The human eye can detect as little as .003(the thickness of a piece of paper) runout on a spinning object.
When I had the (gallop, lumping, porpoising), it was harsh until about 55mph, and it smoothed out at higher speeds. When I slowed into a clover leaf off ramp the lumping started below 50mph even when banking the turn.
I don't know how to make it any clearer. After I balanced the wheel the lumping decreased. Removing the front wheel is easy. I bet you have a CycleGear near you. Do you really want to play the dealer game?

https://www.cyclegear.com/store-location

breakinwind;
I don't want to play the "dealer game" if that means going round in circles with the dealer until I stop pushing for a fix. However, the scoot' is new and they SHOULD address the problem for me as the customer. I'm self employed and would go out of business if I treated my customers the way many dealers treat their customers.
I'm an engineer with a small machine shop for making prototypes for customers. From experience it does not take much runout in a wheel to create much more shudder/shake/vibration than a tire out of round or out of balance. My hypothesis is that a tire "amplifies" a wheel's lack of trueness while if the tire is out of round, it absorbs the problem. Yes, it's a hypothesis that is an opinion with no proof. (Like much of the junk on the media at the moment...)
As I stated above, Cycle Gear's home is in my town. We have a store nearby. If I must take on this issue myself, I may have to use their balancing services. Thank you for pointing out their free balancing service. I didn't know they did this!

I know that the shaft on the spin balancer at CycleGear is 14mm, but I don't know what the front axle shaft is. If you can machine a sleeve that will remove the slop between the balancer shaft and the inner race of the wheel bearing, you will get the best balance. The dealer might not have a spin balancer. The only time I won't have my wheels spin balanced, is when it's not available. After my recent experience, no one can convince me that any other method is better than spin balancing.

I'm a prototype machinist for a small company. If you were in San Diego, I'd ask you for a Job

I just checked. The inner race of the wheel bearing is 20mm. So, if you have a sleeve with an O.D. of .785in.(20mm is .7874in) and use a 14mm drill to make the I.D. you would have the needed sleeve.

The difference between static balancing and dynamic balancing is quite clear provided that in either case the wheel is mounted exactly as it would be when fully assembled to the scooter. Even when static balancing the spacer and cones shown are almost essential for an awkwardly shaped scooter wheel.

In static balancing the weights are placed so that the wheel will come to rest randomly because the centre of gravity is situated somewhere (anywhere) on the axis of spin. However this can be achieved with concentrations of weights which are offset on different sides so that when the wheel is rotating there are still out of balance forces.

In most cases if the balance weights are applied equally on both sides or where possible in the centre between spokes there will not be too much problem with dynamic imbalance.

My failed attempts to balance statically are always because I haven't mounted the wheel truly on its working axis.

Want even better? Find a BMW dealer that has a Hunter Road Force Balancer

But is it FREE

you do know that all the tire manufactures at the races tracks use static balancers versus spin balancers.

But do you know why?

because spin balancers have to be calibrated and are only good right after the last calibration. there is no way to know if its off unless its cal'ed every time before use.

static balancers are actually more accurate as the heavy side will always fall to the lowest point , the six o'clock position. Once the proper amount of counter weight is placed and rechecked you should be able to stop the weights anywhere in the rotation and not have the tire rotate.

I always stop mine at the 2,5,7,11 o'clock positions to check for any rotation. if it does I adjust the weights either by position or amount or both.

ps I always add a piece of duct tape over top of the weights to ensure dirt doesn't get underneath and wear away the sticky and then you can lose a weight.

When I used the static balancer with the cones, my rear tire needed 2 1/4 oz. When I made the sleeve for the static balancer, It ran truer and only needed 2 oz. and changed position by 5 deg. When I made the sleeve and had it spin balanced, it needed 1 1/2 oz. and changed position 15 deg.
This experience is open for subjective opinion. My opinion still stands pat

you do know that all the tire manufactures at the races tracks use static balancers versus spin balancers.

But do you know why?

because spin balancers have to be calibrated and are only good right after the last calibration. there is no way to know if its off unless its cal'ed every time before use.

static balancers are actually more accurate as the heavy side will always fall to the lowest point , the six o'clock position. Once the proper amount of counter weight is placed and rechecked you should be able to stop the weights anywhere in the rotation and not have the tire rotate.
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Actually the new computerized balancer recalibrate every time they are turned on.

You stated that spin balancing it BEST, it's only best once the wheel and tire are matched and rode force tested.

My local CG dealer's balancer has a 14mm shaft.

You do understand spin balancers can be set with a variances from a 10 th of an oz up to a 1/4 oz off? So closest they can be adjusted is 10th of an oz.
So that 1/4 oz could just be it's variance that you're seeing.

Most shops have them adjusted between and 1/8 and a 1/4 . Go to a BWM, Mercedes, type dealer and the balancer will be set to 10th of an oz.

I've found after more riding that the "Lumpy" issue is a harmonic that is most prevalent in the 40-55 MPH range. It comes and goes as I ride and seems to have the largest amplitude when leaned over about 15 degrees or more. Strange.
Now that I'm confident that my front tire is in balance, I'd like to check the rear tire's potential for being out of balance by running the scoot' on the centerstand at ~45MPH. I'd be sitting on the scoot' and holding the front brake. Is this a good idea?

My last guess is to jack up the front and check the steering stem for play/binding. Worst case, the shock spring/dampening oil. Other than that, try a new tire.

I checked the fork and it's fine, especially noting the scoot' has <400 miles and is new.
Thanks!

I wouldn't do it. Front brake tight or not, if the rear wheel bounces enough to bounce the scoot off the center stand your BV is moving.

My 2015 bv350 is the same. My local dealer ORLANDO VESPA never checked the bike before they sold it to me. The front tire had a bad flat spot, they replaced the tire and to just find out they never balance tires and wanted to send it to a YAMAHA dealer to get it done. I still have the issue and needless to say this is my last PIAGGIO product and I'm just going to have to live with it. They are clueless on how to fix it and whenever I get on the scooter I'm not happy. They also sold it to me with little coolant and oil in it. When I called them they said it's ok as long as the check engine light did not come on.

I'm not sure I understand. The tires are warranted by the tire manufacturer and not Piaggio. If the new tire has a bad flat spot there is no fixing it....you simply replace the tire. The check engine light is to tell you the oil and coolant is low? Maybe I'm just reading this all wrong.

it ain't the product, its your dealer. there are a lot of great dealers out there a few are on this forum.

when a bike sits for a long time on a showroom floor and never moves they can develop a flat spot. the tire didn't come like that from the factory I can promise you that.
I do think its poor that they don't balance tires or neglecting to do so.

Did they show you the PDI inspection that they are suppose to do prior to you picking it up? This is on the dealer not Piaggio BTW.

No they did not show me the inspection form and this is not the first piaggio scooter I got from them also. I just wish we had another dealer with in scooter distance. We got one in Daytona beach that is like 80 miles away I'm toying with going to from now on. They did replace the tire but it still have front end vibration.

I rebalanced my front tire and the issue remains. Frustrating. I'm probably going to start the dealer dance with A&S in Sacramento where I bought the scoot' three weeks ago. I really dislike the dance as dealers often treat customers with little respect. The A&S sales person was not very professional but the price was attractive and I certainly didn't expect a tire problem from Michelin. I also just found that the high beam on the upper headlight burned out.

The vibration may be what killed your headlamp bulb. If you examine it closely you will probably see a clean break in the filament rather than a burnt and sooty look. This indicates a mechanical failure rather than being burned through by ageing or by air ingress through the glass.

I flow to Boston and road 564 miles to get my first scooter home. So 80 miles is nothing

Ya but on a bike with front end vibration it would be like going 15 mph there the entire way

You could pull the caliper and get a static balance on the bike.

WEB-Tech.
I tried that but the drag was too high. Then I loosened the axle to see if that would reduce the drag but eventually had to remove the wheel.
I'm going to remove the rear wheel next. If it is not quite a ways out of balance I'm going to replace the brand new City Grips (it's on a new BV350 with 420 miles) with new Michelin's that are NOT CG's.