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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: oldmansax on July 05, 2010, 12:08:04 PM

Title: Do tires move on the rims with use?
Post by: oldmansax on July 05, 2010, 12:08:04 PM
I started to post this on Sean's thread about balancing but thought better of it. It might be hard to search for later & I don't want to hijack the thread.

I have heard people say truck tires (I would assume they mean any large highway type tire) actually rotate on the rim with use. This argument is used to dissuade folks from spin balancing tires using weights and instead use some type of fluid, powder or centrifugal balls to balance the tires. The reasoning is if the tire moves on the rim it is no longer balanced so we should use something that adjusts to changing dynamics.

If I were still in the trucking business I could just paint a line on a tire & rim & see what happens but I am not.

So, does anyone know definitively if a tire moves on the rim with use? I am really not looking for opinions here unless they are backed up by documentation, studies, or real world experience.

As Sgt. Friday would say, "Just the facts, Ma'am"  ;D ;D

TOM
Title: Re: Do tires move on the rims with use?
Post by: Sean on July 05, 2010, 01:25:52 PM
Tom,

I can tell you anecdotally that, no, ours do not move on the rims.  Over the years I have used marks on both the tires and the rims for various reasons and I have never noted any rotation of the tire with respect to the rim once mounted.

I can also tell you that I used to use Equal (due to the difficulty in finding balancing equipment for my wheels) and I got rid of it.  It did not appear to actually do anything productive to balance the wheels, and it made maintenance a nightmare (air has to be 100% dry when you top up the tires; there need to be little screens on the valves to keep the powder from coming back out the valve, lodging in the core, and causing a leak, etc. etc.).  After finally getting the steers spin-balanced, we've had the best ride and least tire wear of our entire operating experience, which is why I am looking to do it every time we rotate now.  Still looking for a shop, BTW (oops... sneak hijack there).

-Sean
http://OurOdyssey.BlogSpot.com (http://ourodyssey.blogspot.com)
Title: Re: Do tires move on the rims with use?
Post by: gumpy on July 05, 2010, 02:41:45 PM
No. They don't move on the rim.

I have mine balanced, and use Centrimatics on the steer and drive axle. Just replaced the steer tires and put the old ones on the tag.

Keep them inflated properly.

Title: Re: Do tires move on the rims with use?
Post by: luvrbus on July 05, 2010, 03:03:22 PM
I never saw one move on a bus, they will move on a heavy haul truck Cole has that problem on his trucks loaded with 100 tons his KW's will spin the tread off the casing sometime also but that is a different world than a bus.


good luck
Title: Re: Do tires move on the rims with use?
Post by: trapper on July 05, 2010, 07:02:46 PM
In the past when I ran tube type tires on my dump trucks the tires would spin on the rim if you were loaded and had to put a real strain on the driveline to get out of a hole. The tire would spin on the rim and it would shear of the valve stem and then not only were you in a hole but you also had a instant flat. Since we have used tubless tires I have never had one spin. Maybe the tube type tires are where the story started.
Title: Re: Do tires move on the rims with use?
Post by: oldmansax on July 05, 2010, 07:58:50 PM
Quote from: Sean on July 05, 2010, 01:25:52 PM
Still looking for a shop, BTW (oops... sneak hijack there).
-Sean
http://OurOdyssey.BlogSpot.com (http://ourodyssey.blogspot.com)


Nothing worse than a SNEAKY hijacker!   ;D

I have a device that goes on the hub before the rims are installed that has a bead around the edge with several balls (loose) in it. I assume (always a risk!) the balls move in the bead to balance the tire as it spins. Is this the same device as the Centrimatics Gumpy is using?

TOM
Title: Re: Do tires move on the rims with use?
Post by: bevans6 on July 06, 2010, 03:43:03 AM
http://www.centramatic.com/Home.aspx (http://www.centramatic.com/Home.aspx)

haven't read the site yet.

brian
Title: Re: Do tires move on the rims with use?
Post by: TomC on July 06, 2010, 08:45:44 AM
After 1.3 million miles of driving cross country, I've come up with a simple solution to balancing.  When buying new tires-spin balance ALL tires.  If you have a blow out, make sure the tire guy marks the tire and remounts it in the same location-careful of not knocking off the balancing weights (if you have aluminum wheels, they will be of the stick on strip type).  If the tire guy knocks off the weights, then get the tire spun balanced before mounting on the bus again.  You'll have the smoooooooothest ride ever.  Good Luck, TomC