tire balancing: Dyna beads

Has anyone used this product for tire balancing?

http://www.innovativebalancing.com/index.php

Comes up occasionally on the Ducati forums. People who run them generally like them. People who haven't tried them insist they couldn't possibly work and say that anyone who would use them must be an idiot. Lots of flame wars...

Sounds just like the single Carb /dual Carb ongoing argument. It is tough to get balanced information on any forum.
People tend to think whatever they are doing is the only way, whatever the topic.

Glen

Also lots of reviews, opinions, etc. on Goldwing Forums http://www.gl1800riders.com/forums/index.php

debby said:

Comes up occasionally on the Ducati forums. People who run them generally like them. People who haven't tried them insist they couldn't possibly work and say that anyone who would use them must be an idiot. Lots of flame wars...

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That was my feeling, until I saw the following video.

https://www.youtube.com/watch?v=eq263AY ... redirect=1

My engineering mind tells me if the wheel is mounted on a rigid shaft (like a tire balance machine), the beads will not redistribute, and the naysayers will say "see, proof it is snake oil". The video has me re-thinking...I can fathom in my mind that the beads redistribute when the wheel hops, I just havent worked out why they end up exactly countering the wheels dynamic heavy spot.

I would like to get input from some of the guys on this forum, who's experience and expertise I respect. There are a bunch of testimonials out there.....who knows if put out by the manufacturer?

Ancient technoglogy before any of us born and I had bead filled rings on my car wheels in the late 60's. Some HD flywheels have a groove and cap tube 1/3 full of mercury for similar benefit. As mentioned a static fixed shaft does not move when imbalanced so beads just collect in a lump. I can not explain the physics yet but some how the beads tend to get throw off the heavy area and spread out evenly from there. I also do not know why a watery liquid wouldn't work as well. I sure love the water/anti-freeze in my small tractor but it can go fastest enough to lift the 2/3 full mix all the way around. We weebles wobble but don't fall down sort of sense. Anything level here has a roof over it.

https://www.youtube.com/watch?v=94-CdexJ3Xk

If this works in a tyre, then, why wouldn’t it work inside a crankshaft :?:

It would cut the vibration down no end and stop my teeth filling falling out :!:

Bernhard said:

If this works in a tyre, then, why wouldn’t it work inside a crankshaft :?:

It would cut the vibration down no end and stop my teeth filling falling out :!:

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The crankshaft is intentionally out of balance, in order to compensate for the rods and pistons. Because there is both a rotating mass (the crankshaft) and reciprocating mass (part of the rods and the pistons) there can never be an exact balance factor over the entire RPM range.

A hollow electric motor armature could be so balanced, if this works (seems like it does).

hobot said:

I also do not know why a watery liquid wouldn't work as well. I sure love the water/anti-freeze in my small tractor but it can go fastest enough to lift the 2/3 full mix all the way around. We weebles wobble but don't fall down sort of sense.

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C'mon, Hobot....those wee wobbles are the chevron tires! Thanks for the link...if anti-freeze/water works in trucks, why not MC's? Who is going to be first to give it a try?

Slick

Here ya go spinning up toxic heavy metal inside Harley flywheels either as a cool fad or a sad fact. In the case of liguids or fine enough fluids beside the evening out to least energy state it can also help absorb hi freq shocks of combustion or striking road hazard edges. A down side to consider is the frictional heating but I'd think a slurry of various size particles in a liquid slightly thicker than water might work a DIY treat. Big tire cleats don't make em thump imbalanced just sing and hum and throb loudly.

Here's where Sun-Tech's active balancing technology comes in. It uses a circumferential mercury-filled bladder attached directly to the rotating mass. As the object spins, centrifugal forces cause the mercury to migrate within the bladder to an area that is directly opposite any imbalance. The mercury migrates not in a blob but in a thin bead, so it doesn't add any imbalance of its own. Since the mercury is not constrained, it can move around as needed in response to changes in rotational speed-hence the designation "active balancing."

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https://www.balancemasters.com/harleybikespread.html

An interesting link, Hobot. I can accept the mercury bladder inside a crankshaft will dampen vibes at a steady RPM, like cruise. however when going WOT there may not be time for the Hg to adjust as the rpm goes up.

In a wheel that is balanced, no adjustment is necessary if the rpm increases. In a rotating/reciprocating mass assembly, a balance factor that is smooth at one rpm, might be very shaky at another. I can accept the Hg will eventually adjust for various steady rpm's, but I have to wonder what will happen in quick up/down changes in rpm. Not disputing this....just wondering.

From an environmental standpoint, I prefer to have anti-freeze in my tires, rather than a Hg bladder on the hubs (Balance Masters).

Hobot, you seem to be an instant reference librarian.....do you know of suggested amount of anti-freeze vs tire size?

Slick

Hm i admit this fluid dynamic balancing per fixed plane crankshaft vs moving wheel axle has me mystified. I'll ping the crank guys and Dyno bead dudes to see if they can point out the physics trick they are working with. You are right Slick, that changes in rotation speed &/or combustion shocks or road wheel shocks would sort of explode the fluids for a few rotations. Why it all don't just collect in one big puddle is beyond my physics so far. I see mercury filled chamber on archery bows to dampen their string snap shocks. I saved the Dyna Bead package and label, somewhere in living room shop, but don't remember if it was you that sent them. Want a nice gremlin bell?

The anti-freeze to water ratio is how ever much not to freeze in your climate into a lump to sling around. In hwy speed road tire the fluid mass added would be same as dyna bead recommendation but in traction tractor tires we put in as much as ya can with valve stem at highest point to fill, front tires too, then some metal weights on wheels and other places to boot. I'll should be able to tell on Peel if the beads or fluid dampers down the tire resonance for more traction but doubt I could on any thing else. I can't ever get over how transparent and totally separating of all vibe inter reactions Ms Peel set up reveals.

I would go with a 50/50 water / antifreeze mix....same as recommended for most liquid cooling auto use.

The amount to use, IMO, should be more than the equivalent weight of dyna beads, as some water will wet the inner tube/tire surface and be less able to migrate as loose beads will. I am guessing 50% more would be a starting point.

As for the physics....the way I "see" it is the wheel has a vibratory amplitude ( which it does not if rigidly mounted as on a tire balance machine) and it moves away from the lump of beads ( or liquid) leaving beads ( or liquid) momentarily suspended. The beads or liquid thus return to the inner tire surface somewhere else. The process continues until vibratory amplitude is nil to cause further suspension.

We need a forum member who is a solid body mechanics expert to chime in on this....I am a fluids guy, definitely non-solid.

Slick

The 50/50 is plenty fluid enough not to hesitate or pile up anymore than dry beads. There is always some down side to adding mass to wheels so more ain't better and best to balance wheel with proper weights first.

Makes sense if the wheel heavy area moved suspened axle that direction it would tend to lighten the layer of fluid over it to spread out from there till lowest energy state.

hobot said:

The 50/50 is plenty fluid enough not to hesitate or pile up anymore than dry beads. There is always some down side to adding mass to wheels so more ain't better and best to balance wheel with proper weights first.

Makes sense if the wheel heavy area moved suspened axle that direction it would tend to lighten the layer of fluid over it to spread out from there till lowest energy state.

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Lowest energy state is good explanation, Hobot. (also called minimum entropy production)

Do I interpret HobotSpeak to agree that 50% more weight of liquid vs dynabeads is a good starting point?

The Dyna Bead website recommends removing balance weights, but I agree with you that least weight in the tire is best. I am inclined to also agree with you on attempting balance with external weights.

As soon as I get all the bits of the Atlas back on the Atlas, I'll give it a try.

Slick

I thought I was clear - that similar mass [~1 oz] of anti-freeze as Dyna Beads recommends would be the starting point and aiming for least mass to achieve good road going balance. I do not understand any reason one would need more water mass than dry beads or lead shot as in olden days to achieve good balance. Water absorbs lots of heat and raise vapor pressure in tires more than just bead heated air so reason water based balancing ain't used more generally. Repair after anti-freeze sucks and rust in rims hazard too.

Spin around till smooth on these sites
http://www.leadfreewheels.org/101.shtml

Assume some excess tread weight is present at one point on the tire. As it rotates, this causes an acceleration of the wheel and tire in the direction of the heavy spot. The balancing medium in the tube will flow away from this acceleration until such time when the out of balance situation is corrected. The centrifugal force holds the weight against the outside of the balancing tube.

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http://www.magnumbalance.com/

These flowing balancer products work; I have experience with Suntech's mercury in a steel tube product where a slim round tube filled with some mercury is attached to the circumference of the rim of big truck wheels. They work great, don't break, zero maintenance, virtually perpetual; best product in the field, in my opinion.

The knocks about "poisonous mercury" come from competitors who push inferior products. The mercury doesn't wear out, doesn't clog, doesn't clump, doesn't have to be replaced when the tire is changed, and it doesn't leak out either.