Balancing Flash's Shoes

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Wheelman-111
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Balancing Flash's Shoes

Post by Wheelman-111 »

Greetings:

Just about every iteration of Flash has had this: When you release the handlebars, they jiggle and judder and the mirrors go ablur. These light 10" wheels don't have a lot of kinetic energy compared to, say a 17" car rim, but remove the damping effect of one's hands on the grip, and an unbalanced wheel assembly reveals itself. Enter this $17.00 (+$12 Shipping) eBay rack:
BalStand_resized.jpg
BalStand_resized.jpg (288.01 KiB) Viewed 6603 times
One problem appeared immediately; the bar with the centering cones in the tray is 12.4 mm thick. The front axle is only 10mm. Enter the All-Thread in 10mm size - it's mounted on the balancing bearings above. The problem with the All-Thread is that the threaded surface running on the balancer bearings tended to try to "screw" rightward. This was addressed with some variator rollers I had that happened to be a snug fit on the 10mm rod. Nuts and washers to secure the wheel to the new thinner shaft, and we're off!

The extremely low-friction point lets very small differences in weight symmetry demonstrate itself. The assembly will rotate to the heavy-side-down position repeatedly, swinging like a pendulum but eventually stopping in the same spot every time. A Guess is necessary to see how much weight is needed to balance the assembly. The weight is attached straight across the diameter of the wheel from the "heavy" spot.

So on the first try, the front rim repeatedly settled with the valve at about 4 o'clock.
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BalPos1_resized.jpg (309.14 KiB) Viewed 6603 times
I happened to have some lead weight strips. Note that those little squares are only 7 grams - about 1/4 ounce, but that's really all it needed. I cut one with some metal shears
BalQtrOz_resized.jpg
BalQtrOz_resized.jpg (222.66 KiB) Viewed 6603 times
and glued half on each side of the rim using 3M double-stick tape.
BalWtInstalled_resized.jpg
BalWtInstalled_resized.jpg (279.97 KiB) Viewed 6603 times
I will attempt to attach my first video of the process...Uhh, Nope. The extension MP4 is not allowed. Dang.

Anyway, you just spin the wheel and add weight to the opposite side until it doesn't stop in any particular place repeatedly. And the end result? With only a 7-gram counterweight, Flash now rolls judder-free, even in "look Ma, no hands? mode. My NSS250 Reflex will be getting the same treatment soon.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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