Motorcycle tire changer

[Marcus]

The problem with dynabeads is that people don't read the instructions. The web site specifically says not to use them for racing. They will not work with spin balancers because spin balancers do not have the same dynamics of a vehicle axle. They do not work with low profile tires (car tires) due to the lateral instability. It is important to have enough beads to do the job and no more. Otherwise it can cause problems under hard braking. The website has numbers to show how many beads to use for specific applications. They work very well for trucks and motorcycles. My experience while reading many many forums is that people who have actually used them, and followed the instructions have had good results.

I have two links below that show demonstrations of how they work and one link that shows the Auburn university paper on the truck fuel savings using dynabeads. Draw your own conclusions.


http://www.youtube.com/watch?v=eq263AYgyYg

http://www.youtube.com/watch?v=ullnFQD4F1I

http://www.counteractbalancing.com/report.pdf

[MotorDoctor]

Like I always tell my customers regarding questionable explanations, "if it makes you sleep better at night, go ahead and buy it"

[Marcus]

OK. Now you've done it. I'm going to have to unbalance my perfectly balanced front tire and do a before and after experiment on my Goldwing. I'll let you know how it turns out.

[MotorDoctor]

Now that's what I want to hear Don't accept anything with questionable "engineering", if it sounds too good to be true, it usually is I have to say this though, most people can't tell the difference in wheel balance unless it's waaaaaaaaaaaaaaay out. Goldwings have always cupped the front tires, as does anything else that's big and heavy. I don't think it's a balance issue. You would have to find a nice stretch of road that's smooth, ride up and down a few times at the same speed noting how the ride quality is. Then throw the wheel out of balance by putting a couple of ounces on it and see what happens. With it out of balance, throw in the "magic beans" and see if you notice a difference, like going back to the original configuration. The only problem here is the "placebo effect". If you really wanted to make sure, you would have somebody else make the modifications without you looking so that doesn't taint the data. If it was me making the mods, I would tell you I changed something and not do anything just to see what you say. I've done that more than a few times with people that said they were suspension experts. After our little experiments, they found out that they really had no idea what was going on. They were right about 30% of the time.

[Marcus]

Originally Posted by MotorDoctor

Now that's what I want to hear Don't accept anything with questionable "engineering", if it sounds too good to be true, it usually is I have to say this though, most people can't tell the difference in wheel balance unless it's waaaaaaaaaaaaaaay out. Goldwings have always cupped the front tires, as does anything else that's big and heavy. I don't think it's a balance issue. You would have to find a nice stretch of road that's smooth, ride up and down a few times at the same speed noting how the ride quality is. Then throw the wheel out of balance by putting a couple of ounces on it and see what happens. With it out of balance, throw in the "magic beans" and see if you notice a difference, like going back to the original configuration. The only problem here is the "placebo effect". If you really wanted to make sure, you would have somebody else make the modifications without you looking so that doesn't taint the data. If it was me making the mods, I would tell you I changed something and not do anything just to see what you say. I've done that more than a few times with people that said they were suspension experts. After our little experiments, they found out that they really had no idea what was going on. They were right about 30% of the time.

I was thinking along the same lines as you, but I am trying to think of a way to mount a transducer (maybe a speaker with a weight glued inside the cone) to the fork and record the results during the experiment. I could feed the results into an oscilloscope for a visual representation. Part of the problem is that the frequencies will be in the 0 to 30hz range and most recorders don't have that range on the low side.

If I can work out the bugs, I can split the input signal and record my voice on top of it so I can narrate the speed, braking, and acceleration points. Anyway, I don't know how realistic it is because it sounds like a lot of work. I may just have to to by the seat of my pants.