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[Ironhorse]

I was at a shop the other day and saw one of the techs balancing a new tire on static balancer. It looked like a tuning fork that he set the tire in on a set of rollers. Then he placed weights until the wheet/tire did not rotate to a "heavy spot" down position, meaning it was static in whatever position it was set in. I asked him if it was better than a spin balance and he said it was. He said most racing teams static balance instead of spin balance.

Is one better than the other?

[spydglide]

Did you notice if he was using the old 'lead' weights or something else?  Our local dealership is going away from them...not sure what's going to replace them yet.  spyder

[Ironhorse]

Did you notice if he was using the old 'lead' weights or something else?  Our local dealership is going away from them...not sure what's going to replace them yet.  spyder

I don't think they were lead, but they were the peel of the back and stick on kind. He said the problem with spin balancers is that most shops don't take the time to reclaibrate them regularly and as a result they lose accuracy.

[grc]

I can't think of any situation, especially high speed racing, where static balancing would be preferred over dynamic balancing.  Modern computerized dynamic balancers are much more accurate as well as faster, but of course they cost a lot more than a simple static setup.  Therein lies the real reason for a shop to still use static balancing.

BTW, what does he do about lateral (side to side) imbalance with that simple balancer you described? 


Jerry

[Ironhorse]

I can't think of any situation, especially high speed racing, where static balancing would be preferred over dynamic balancing.  Modern computerized dynamic balancers are much more accurate as well as faster, but of course they cost a lot more than a simple static setup.  Therein lies the real reason for a shop to still use static balancing.

BTW, what does he do about lateral (side to side) imbalance with that simple balancer you described? 


Jerry

Well he had a spin balancer in his shop too, but said that the static was still better. Then he took the tire off the static balancer, put in the spin balancer and it came up balanced, so I guessed it worked. He did that just to show me, a Doubting Thomas, that it would. He was an older guy who cut his teeth turning wrenches for many racing teams in the 80s and 90s. Then he got tired of living out of trailers and went to work for a shop. I have no doubt he knows his stuff.

I'm not sure what you meant about lateral side to side balance.

[grc]

..................................................

I'm not sure what you meant about lateral side to side balance.

Lateral imbalance causes the tire and wheel assembly to "wobble" from side to side.  The type of balancer you described does not measure that form of imbalance, and therefore cannot help you compensate for it.  It might be capable of eventually getting fairly close to the same single plane vertical balance as an average dynamic balancer, after much trial and error, but for high speed applications a dynamic computerized balancer is the preferred method.  I don't think you'll find many professional race shops using static balancers these days either.

BTW, if you use a static balancer it is a good idea to split any weight equally from side to side to avoid adding to any lateral imbalance that might already exist.  I've always found it strange that H-D just sticks all the weights, no matter how many, on only one side.  But then with the sort of tolerances Harley uses I guess it doesn't matter to them. 


Jerry

[NickD]

I fabbed up a cheap static balancer using two jack stands, some bearings, and a bit of drilling and welding.



I already had the jackstands and the bearings I got in a local skateboard shop (8 bearings for $12) for the axle to ride on. When I asked the kid behind the counter if these were the best bearings he had and he said yes! And he added, "They are lubricated with speed cream!" LOL!





For weights you can use the stick on type or the ones that wrap around the spokes. Just make sure you do it with the brake disc on the assembly as they affect balance too.

It should be said that modern manufacturing techniques in both tires and wheels have made balancing less critical than it once was. Sure, no tire or wheel is perfect but the amount of imbalance is such that in normal street riding you'd probably never notice it. Balancing can't hurt, of course, and the reason I did mine was since I built the bike I needed to rule out balance issues in case there were problems on the first rides. On an already running bike I would have skipped it all together.

 

[spydglide]

I beg to differ that the new wheels are all close in tolerance. A buddy just bought new wheels for his Street Glide from MoCo and they were so out of balance that dynaBeads wouldn't correct them....had to use gobs of weight to finally get them in balance.  It was the wheels, not the tires.  spyder

[Chains]

I beg to differ that the new wheels are all close in tolerance. A buddy just bought new wheels for his Street Glide from MoCo and they were so out of balance that dynaBeads wouldn't correct them....had to use gobs of weight to finally get them in balance.  It was the wheels, not the tires.  spyder

You are right, depends on the machinist and the set up wether the "new wheels"  turn out right.  Crappy set up or operator, bad wheels, bad balance.

[Ghost__Rider]

This is what I use..........  http://marcparnes.com/

Works dam good.