Do you balance the wheels on your racing car?

[Sumflow]

Originally Posted by Kroggers

Can we assume from this that you do not balance ...

I think the main question should be is static balance alright, or do we need dynamic balance?

[Jittsl]

I think the main question should be is static balance alright, or do we need dynamic balance?[/QUOTE]

Hmm. I must confess I have never seen the distinction made above. Sumflow, did you make that up just to fool us dumb folk?

The "dynamic imbalance" you show in the image looks a lot like what I would call a bent wheel. If true then I probably don't accept dynamic imbalance. If the wheel doesn't run true I throw it out.

If it appears to run true but gives a little wobble in the steering wheel or shake in the car (apparently the output of static imbalance by the previous diagram) then I just live with it - I got plenty of other stuff to really worry about.

Laurie

[stephen wilson]

I think the concept is this: If the tire has a "heavy" spot towards the outside edge, and you put the balance weight on the inside edge of the rim, it will balance in a static test, but not dynamically. The offset between the two masses causes a "wobble" , that axis is what the drawing is trying to represent.

[BYprodriver]

Originally Posted by Sumflow

I think the main question should be is static balance alright, or do we need dynamic balance?

Static imbalance is a up & down force

Dynamic imbalance is a side to side force

[Jittsl]

Originally Posted by BYprodriver

Dynamic imbalance is a side to side force

What (other than a bent wheel) would cause a side to side force? Seems to me that all forces on a unbent wheel (ie forces derived from rotation around a single fixed axis) would be "up and down".

[stephen wilson]

Originally Posted by Jittsl

What (other than a bent wheel) would cause a side to side force?

Read post #24.

[Jittsl]

Originally Posted by stephen wilson

Read post #24.

I did steve but here is my problem: if I have a heavy spot on the outside edge of a wheel the compensating weight would be placed on the same edge 180degrees away. Wouldn't it? I am no expert so I'm looking to understand here.

[stephen wilson]

Originally Posted by Jittsl

I did steve but here is my problem: if I have a heavy spot on the outside edge of a wheel the compensating weight would be placed on the same edge 180degrees away. Wouldn't it? I am no expert so I'm looking to understand here.

The key is, if you're not dynamically balancing, you won't know if the imbalance is towards the inside or outside, so getting the weight in the exact right spot is a crap shoot.

[Jittsl]

Originally Posted by stephen wilson

The key is, if you're not dynamically balancing, you won't know if the imbalance is towards the inside or outside, so getting the weight in the exact right spot is a crap shoot.

That makes it clearer. So then, When my guy is spinning my wheel on a machine is he doing a dynamic balance? If not can someone describe the process difference?

[BYprodriver]

Originally Posted by Jittsl

What (other than a bent wheel) would cause a side to side force? Seems to me that all forces on a unbent wheel (ie forces derived from rotation around a single fixed axis) would be "up and down".

lateral runout in the wheel &/or tire or brake rotors

uneven tread wear

damage

heavy spots

nothing is perfect