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Thread: can we go deeper on Dyna Beads and balancing?

  1. #16
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    Quote Originally Posted by marchyman View Post
    I believe it would be functionally equivalent at a constant velocity over a smooth road. The differences would occur as velocity and/or road surface changes. I suspect they will work well for the RT rider going down the freeway, but maybe not so well for a GS rider in the gravel or a sport rider at a track day. Those are the kind of tests I wish someone like MCN would perform. Of course those tests would be a lot harder than putting a wheel on a spin balancer.
    I totally agree. Now how about that bumble bee thing?

  2. #17
    Certifiable User Mike_Philippens's Avatar
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    Problem with these things is about the same as tyre discussions. Most riders are not able to tell the difference between two tyres because normally you'd change tyres when the old one is gone. Even if you mount a 'lesser' tyre, you'd notice an improvement over the old situation (to which you were grown accustomed to).

    Now, the only way for an average driver (there are always super technicians who can smell the difference, so we won't count them) to notice differences between tyres is when you go to a track, have 2 of 3 sets of wheels at your disposal and try every set for 10 laps or so. Then you have the same bike, driver, track and weather conditions.

    The same applies to these bead things. Not everybody can change their own tyres and do the balancing themselves. So how on earth can you compare it? First you need to try how an unbalanced wheel feels like and what it does to you wheel with regard to wear. Then you should change to a static balanced wheel and notice how different it feels. After that, try it with the magic beads and try to notice the difference.

    Just out of curiosity: what is the problem the beads should solve? When I have my tyres changed, they balance my wheels. I can imagine that with the wearing of the tyre, the balancing goes off. But I never really noticed a problem with that. It's not that the bike starts handling like a pig or something. So...what's the big thing with the beads anyway? What do the solve actually?
    -=- if you always see the road ahead of you, it's not worth the trip -=-

  3. #18
    Quote Originally Posted by warredon View Post
    I did notice one big improvement though, it is the cupping or scalloping or whatever you call it. I've only been riding BMW's since the 70's, so I don't have near the experience that some of the older /5 riders have. It seemed whatever tire I used on the front of my machines, it would always scallop. Now like magic, these last two front tires (the ones with the Beads) didn't scallop. If they did, it was almost indiscernible. They were two different brand of tires BTW, a Michelin and a Pirelli.

    Now I don't have a clue how in the world the beads could help a scalloping problem, and I'd be the first to admit that it could very well be a coincidence. It just seems odd to me that as soon as I started using the beads, the scalloping problem improved immensely. I will probably try them in my next front tire, if the scalloping is still gone then I plan on not using them in the next tire just to see if the scalloping returns. I have heard that front braking technique can contribute to scalloping, I don't know.
    The same happened to me: same bike, same rider, same roads, two sets of the same type of tires. The first set cupped badly and quickly, the second almost not at all. The only intervening variable was the Dyna Beads.

  4. #19
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    Quote Originally Posted by alzyck View Post
    I totally agree. Now how about that bumble bee thing?
    Are Carpenter Bees & Bumblebees related?The former eat my house and the latter sting big time! I am one of the fools that uses them and find them easy to capture using an old hillbilly trick(I didn't know indians wore panty hose?) that includes dismounting the tire and dumping them on a newspaper,etc.. No, I don't wash or clean them either, simply reweigh them and place back in the tire. I bought a bunch on an Advrider group buy and keep to the 1 oz fron/2 oz rear amt.. I have a electronic scale I bought new on ebay for 99 cents that goes up tp 76# and weighs to the tenth of an oz!!! It weighs the same as my local USPS scale.
    I have placed them in maybe 6 sets of tires and get better than most mileages. As to the valve thing-a blast of air prevents that problem as does simply having the valve at above bottom road position. Whatever the little buggers do in there it works for me. As to the GS thing, I don't see having a muddy tire being in balance anyway or does it matter at slower speeds. The only wear I see that is noteworthy is my rears getting the center wear from slab miles.
    I have mentioned this before, but Goodyear used to place tire boots inside truck tires(in the factory) that failed to meet factory standards that were not possible to achieve via grinding the tires outer tread surface. I was there to do repair work on the grinding machine. As lead in the environment is a serious concern that dynabeads solve I have wondered if there is another solution to tire balance besides beads and lead free weights? Perhaps using specific weight boots/patches inside the tire would work? Are these out there & available now?

    Also , does anyone know what out-of-balance standard is used for motorcycle tires? At Goodyear(1960's & 70's) we had a balance machine that all car passenger tires went through after human visual inspection and white sidewall grinding. A drop of one of three colors of wax identified the tire as havng met a standard, what with one color indiacating that it was suitable for thr OEM ,i.e., new car factory. The tires then went to a force variation machine that inflated, then used an ultra sensitive load cell to determine structural defects. I would like to hear /read something of real substance about MC tires but every article I have ever read was so generic as to pass for a free ad for the bike tire mfgs.! Never do they really touch on standards or unique processes that being what "trade secrets" are made of, I suppose.
    Last edited by kantuckid; 05-15-2011 at 07:40 PM.

  5. #20
    Unfunded content provider tommcgee's Avatar
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    Quote Originally Posted by rockbottom View Post
    The same happened to me: same bike, same rider, same roads, two sets of the same type of tires. The first set cupped badly and quickly, the second almost not at all. The only intervening variable was the Dyna Beads.
    I've been through 3 or 4 sets of the same tires on my current ride and they all wore differently. Go figure.
    Salty Fog Rally 2007, 2009, 2011, 2012, AND LOOKING FORWARD TO 2014!

    -Tom (KA1TOX)

  6. #21
    Quote Originally Posted by tommcgee View Post
    I've been through 3 or 4 sets of the same tires on my current ride and they all wore differently. Go figure.
    Check. That is a possibility--it may have been coincidence. (I'm a social scientist so my mind works by assessing plausible causality).

  7. #22
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    My 2 cents

    I've been using DynaBeads for 3 sets of tires now. At first I didn't understand the physics of the principle so I read a lot and watched the infamous videos until I got it. It's very counter-intuitive and unless you're good at that sort of thing or curious enough to bang your head against it until you understand, you may not. This is indeed as polarizing as any oil thread, you'll find smart folks on both sides.

    Here is some food for thought.

    Dynamic spin balancer issue:
    MCN made a mistake with this test. There is a fundamental difference between a wheel/tire assembly spinning on a spin balancer, and on a vehicle axle.
    The vehicle axle is free to move up and down whereas the spin balancer axle is not.
    If you need proof, go to the tire store, grap the balancer axle and try to move it. Now grab your motorcycle FD and try to move that.
    In the first instance, be careful with your back, in the second, don't tip the bike over.
    The MCN test indicated that the wheel/tire required weights in the same place, beads in or not. The reason was, the beads distributed evenly around the tire perimeter because there was no eccentric axle motion.

    When not to use DynaBeads:
    a/ Some tire manufacturers say they will void warranty. If you care, don't use them.
    b/ Don't put them in your track bike. The violent wheel RPM changes send them flying around the tire and racers don't like them.

    How they work:
    This is difficult, I've not yet found an "Oh yah" explanation. Here's what works for me:
    An 'out of balance' wheel/tire assembly causes the axle to rotate off-center or eccentrically. An off-center excursion forces some beads to collect opposite to its direction. In a few rotations, the beads collect in a distribution that nulls out any off-center excursions.
    If you have too few in the tire, there won't be enough balancing mass and the assembly will still shake, although less.
    If you put in more than necessary, the excess beads will collect evenly around the tire and not have any effect on balance.
    The net result is that the mass distribution will match whatever conventional lead weights are required.
    Some people report an improvement in cupping, I don't have anything to add to that. I will say however, the beads will continually shift to match any uneven tire wear, so have that advantage over fixed weights.

    Recommendations:
    Innovative balancing makes recomendations on the amounts to use. I've followed those with no issues.
    I recommend putting them in through the valve stem.
    I also recommend removing a tire with little regard to the fact that beads are inside. Once you get the tire half off, you can recover 98% of the beads with a paper scoop, sweep the rest up and throw them out. The old beads will have some 'stuff' in with them which I blow away with light air pressure. Weigh the old beads and top up to the recommended mass.


    Lastly:
    Have an open mind.
    If you really don't think they work then provide reasons why.
    Not everything is obvious, who'd have thought that a nut and bolt would stay torqued without glue?
    Sometimes, the universe works with us and this one is truly a gimme.
    Mike Marr
    1978 Yamaha XS750 (Needs rings), 1996 BMW R1100RS, 2004 Honda CRF230F

  8. #23
    Unfunded content provider tommcgee's Avatar
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    Quote Originally Posted by MotorradMike View Post
    If you really don't think they work then provide reasons why.
    I tried them in a new unbalanced front tire that had been on the bike for a week -- I got increased vibration between 60-70mph. Took them out and the problem went away. I realize there are many who say the opposite happened. All I have to go on is my own experience with them.
    Salty Fog Rally 2007, 2009, 2011, 2012, AND LOOKING FORWARD TO 2014!

    -Tom (KA1TOX)

  9. #24
    Benchwrenching PGlaves's Avatar
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    "Dynamic spin balancer issue:
    MCN made a mistake with this test. There is a fundamental difference between a wheel/tire assembly spinning on a spin balancer, and on a vehicle axle.
    The vehicle axle is free to move up and down whereas the spin balancer axle is not.
    If you need proof, go to the tire store, grap the balancer axle and try to move it. Now grab your motorcycle FD and try to move that.
    In the first instance, be careful with your back, in the second, don't tip the bike over.
    The MCN test indicated that the wheel/tire required weights in the same place, beads in or not. The reason was, the beads distributed evenly around the tire perimeter because there was no eccentric axle motion."


    OK. But how do the beads know whether that up-down is caused by an imbalance or bumps. If they redistribute due to the up-down so be it but the balance doesn't change every time you hit a crack in the pavement.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  10. #25
    "Running Out The Clock" grafikfeat's Avatar
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    Quote Originally Posted by tommcgee View Post
    I tried them in a new unbalanced front tire that had been on the bike for a week -- I got increased vibration between 60-70mph. Took them out and the problem went away. I realize there are many who say the opposite happened. All I have to go on is my own experience with them.
    Maybe you were now feeling that over due valve adjustment?

    Just kidding... I do very much agree w/ your assessment.
    Go on your own experience.

  11. #26
    Lucky motorradmike's Avatar
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    Quote Originally Posted by PGlaves View Post
    OK. But how do the beads know whether that up-down is caused by an imbalance or bumps. If they redistribute due to the up-down so be it but the balance doesn't change every time you hit a crack in the pavement.
    Good point Paul:

    I don't have a good answer for that. For sure, the beads will shift in response to a bump in the road. Perhaps they would make things worse in a washboard situation - don't know. However, I will say, if the road is bumpy, balanced wheel/tire assemblies are likely secondary and one ought to slow down to maintain control.

    You've brought up something I haven't seen before.
    Keep thinking.
    Mike Marr
    1978 Yamaha XS750 (Needs rings), 1996 BMW R1100RS, 2004 Honda CRF230F

  12. #27
    "Running Out The Clock" grafikfeat's Avatar
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    I read somewhere on some board a long time ago that they are constantly redistributing.
    That being said...
    After you come to a stop to avoid a pot hole and slowly roll forward there is no need for tire balance.
    At the higher speed/revolutions the beads will redistribute again.

    As for cracks in the pavement the beads would need to overcome inertia to redistribute on such a small 'blip'.

  13. #28
    Benchwrenching PGlaves's Avatar
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    Quote Originally Posted by GrafikFeat View Post

    As for cracks in the pavement the beads would need to overcome inertia to redistribute on such a small 'blip'.
    A couple of times when on the road I have omitted balancing a tire and have notices a minor thumping or vibration from the imbalance. But the minor thumping that was detected was slight compared to bumps or even pavement seams as on a concrete Interstate. The movement if any from the imbalance was certainly less than from the pavement cracks.

    As I said in my first post, I don't know if the beads work or not, but I am trying to understand how they would work, assuming that they do.
    Paul Glaves - "Big Bend", Texas U.S.A
    "The greatest challenge to any thinker is stating the problem in a way that will allow a solution." - Bertrand Russell
    http://www.bigbend.net/users/glaves

  14. #29
    "Running Out The Clock" grafikfeat's Avatar
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    Quote Originally Posted by PGlaves View Post
    As I said in my first post, I don't know if the beads work or not, but I am trying to understand how they would work, assuming that they do.
    I'm right with ya on that...

    As I understand there are reasons they are the size they are and ceramic as well.
    Frost clumping is one.

    For my learning curve(s) there are two ways I learn.
    Doing and asking questions.

  15. #30
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    Dyna Beads

    It's surprising to me that the company that manufactures Dyna Beads hasn't commissioned a non-biased, i.e. university, research study to determine the efficacy of Dyna Beads. I don't know what the going rate might be for such a study, but based on my university experience, I'm betting that a simple study could be had for less than $20K. Just a guess. Every motorcycle forum that I've checked has the same discussion re: Dyna Beads. And it's just like ours, some folks swear by 'em, others swear at 'em!

    Piperjim

    '95 R1100RS
    '61 John Deere 3010 LP

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