Class A wheel balancing

[dmctlc]

Originally Posted by Tireman9

First I would confirm OOR so you know the tire is properly mounted and the beads are properly seated and the tire is actually round.

As I showed on my blog you can balance a cement block but I doubt you would like the ride.


I would suggest an on vehicle spin balance as the heavy hub and brake components can be out of balance too.

What you referenced to as "on vehicle spin balance" is what I referred to earlier that a friend had done on his Ckass A gasser. My understanding is very few shops do thus type of balancing as he said they actually shave the sidewall which i guess they also use to do for race car tires. "Tire truing is a process that renders the tire absolutely round by slowly spinning the tire in its normal position while shaving the high spots with a high-speed razor mechanism. The result is an equal distance from the centerline of the axle, assuring the smoothest ride possible." Results was like night and day.

[Tireman9]

Originally Posted by dmctlc

What you referenced to as "on vehicle spin balance" is what I referred to earlier that a friend had done on his Ckass A gasser. My understanding is very few shops do thus type of balancing as he said they actually shave the sidewall which i guess they also use to do for race car tires. "Tire truing is a process that renders the tire absolutely round by slowly spinning the tire in its normal position while shaving the high spots with a high-speed razor mechanism. The result is an equal distance from the centerline of the axle, assuring the smoothest ride possible." Results was like night and day.

Out of round and out of balance are two different things. A spin can reveal out of round. OOR can be caused by the wheel mount to the hub being wrong or the tire to the wheel being wrong or the tire itself being OOR due to some manufacturing issue.


In "Showroom Stock" racing that i competed in we did shave the tread but that was not to get the tire round but to decrease heat and tread tearing.


Old bias tires might benefit more from tread truing (shaving) but modern radials from any of the major name brand tire companies should not hat this problem.


Some poor ride problems can be fixed by simply ensuring the wheel is properly mounted tot he hub. This means that the lug nuts are only finger tight till all the nuts are on, then torque to 10% in the appropriate pastern as I covered in my blog, then torque to 60% then to 100%.


Some times the installer is in a hurry and tightens one nut 100% then installs the other nuts. This almost guarantees the wheel is not centered properly.

[dmctlc]

So I was talking to my buddy in his case they didn't shave his MHs tires threads but actually the sidewalls to balance them and it spins balances the tires while still on the coach. The place does a lot on big trucks etc. I was thinking it would weaken the sidewalls but he said it does take a lot off but it worked for him...huge difference he was having major issues even went back to the Manufacturers who did somethings but still had shimmy hence he went to the shop a world of difference.

[Tireman9]

Originally Posted by dmctlc

So I was talking to my buddy in his case they didn't shave his MHs tires threads but actually the sidewalls to balance them and it spins balances the tires while still on the coach. The place does a lot on big trucks etc. I was thinking it would weaken the sidewalls but he said it does take a lot off but it worked for him...huge difference he was having major issues even went back to the Manufacturers who did somethings but still had shimmy hence he went to the shop a world of difference.

"Shimmy" would suggest that the tire/wheel assy was not mounted correctly to the hub, or tire not centered on the wheel which is easy to get wrong with 16.5, 17.5, 19.5, 22.5, and 24.5 sizes.

[TimmyB]

So, I have learned an immense amount from this thread. Never knew about beads or centramatics before!

I want to make sure I'm understanding this correctly. I am pretty sure that I am going to add Centramatics to my coach this year. Since many (especially the experts who have worked in the truck tire industry) feel that balancing on the rears is overkill for a variety of reasons, should I really just add them to the front and then add the rears later if I decide that they need them? I'm not trying to cheap out; I'm just making sure not to throw good money at a problem that doesn't exist.

Thanks for any advice.

[Ivylog]

Originally Posted by Tireman9

Some times the installer is in a hurry and tightens one nut 100% then installs the other nuts. This almost guarantees the wheel is not centered properly.

So this applies to hub pilot rims???

[Tireman9]

Originally Posted by TimmyB

So, I have learned an immense amount from this thread. Never knew about beads or centramatics before!

I want to make sure I'm understanding this correctly. I am pretty sure that I am going to add Centramatics to my coach this year. Since many (especially the experts who have worked in the truck tire industry) feel that balancing on the rears is overkill for a variety of reasons, should I really just add them to the front and then add the rears later if I decide that they need them? I'm not trying to cheap out; I'm just making sure not to throw good money at a problem that doesn't exist.

Thanks for any advice.

Yes. In general larger RVs only need the fronts balanced.

[Tireman9]

Originally Posted by Ivylog

So this applies to hub pilot rims???

Hub Centric AKA Hub Pilot are less prone to off center wheel/hub mounting issues.

[TimmyB]

Originally Posted by Tireman9

Yes. In general larger RVs only need the fronts balanced.

Thank you!

[Ivylog]

Originally Posted by Tireman9

Hub Centric AKA Hub Pilot are less prone to off center wheel/hub mounting issues.

And how long have they (hub pilot) been used on MHs with 22.5 tires? Doubt even a newbie would tighten the first nut to 100%, if possible.

PS: how much balancing does 5 oz do on a tire that weighs 100+ lbs? My 315s weigh 150 lbs... that works out to 0.2%.

[Tireman9]

Originally Posted by Ivylog

And how long have they (hub pilot) been used on MHs with 22.5 tires? Doubt even a newbie would tighten the first nut to 100%, if possible.

PS: how much balancing does 5 oz do on a tire that weighs 100+ lbs? My 315s weigh 150 lbs... that works out to 0.2%.

First that is not how balance of a tire works. If you place 5oz in the tread area that would be about 100 inch-OZ out of balance ( 5oz at 20" radius).


Tire ride is complex. Ride disturbance can be because of balance or because the tire is Out of Round or the round tire is mounted out of round.


A tire can be out of balance if a splice of body ply or sidewall or belts or tread is heavy or light. Or a combination of the above.


I only offered comments about mounting as that can also contribute to ride discomfort. Solving a ride problem can be difficult. Sometimes it is impossible if the expectations are not able to be meet with a reasonable level of effort.

[Jchemie]

Had a slight mis-alignment on my coach (class A, 35’) which caused a front tires to cup on the outer edge. Got an alignment done, front two tires swapped out for the 2 left rears. Drove it back home, an 80 mile trip. Steered great, but had a little rumble from the rear. Two weeks later I installed those Centramatics on all 4 corners. Next trip, wow, what a difference! Smooth, fuel mileage went up .5 mpg. Best investment. Yes, driving along a rough road or one under construction at speeds over 45 did cause the balance rings some confusion but slowing down to 20 mph or taking the next exit ramp and re-entering the hiway again took care of the rumble. Note: Just remember to inform the tire shop on your next stop you have them on and visually check that they are on before leaving because sometimes they “forget” to re-install them and have no proof you ever had them after you leave. Just saying....

[joelsplace]

Someone asked "why put pretty aluminum wheels one the inside?"
The answer is around 100lbs weight savings per axle. It makes the ride better and allows another 100lbs of capacity if you are at your maximum legal weight.
That brings up another question. How much do Centramatics weigh?

[twinboat]

Originally Posted by joelsplace

Someone asked "why put pretty aluminum wheels one the inside?"
The answer is around 100lbs weight savings per axle. It makes the ride better and allows another 100lbs of capacity if you are at your maximum legal weight.
That brings up another question. How much do Centramatics weigh?

So, total saving 100 lbs. There is only one dual axle, unless you have a HD truck chassis.