22 or 24 tires? - Page 2
 

22 or 24 tires?

Started by daddysgirl, January 22, 2017, 10:27:16 AM

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jcussen

Stay with 22's Had to get 305/75/24.5's last year.  $900 each!
95 newell 45ft 505hp

TomC

Going from 12R-22.5 to 11R-24.5 is going from 486 to 476 revs per mile. So if you're turning 1800 at 65 with the 12R's, then with the 11R's you'd be turning 1763-not really worth it. Better to put in a B500 Allison with it's two overdrives of .74 and .64. Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Seangie

We have no tags and our ride height is on the low side in our Eagle 10S.  Because of this we run 24.5's

I'd love to run 22.5's but it just won't work with our setup.

I'd stay with 22.5's for the higher rpm's and slightly less weight as well as wider availability.

-Sean
'Cause you know we,
we live in a van (Eagle 10 Suburban)
Driving through the night
To that old promised land'

daddysgirl

I had no possible way to know when I posted this question how important and ironic it was going to be.

I am So very grateful for all of your input. I've got 12R22.5 on all Alcoa wheels now. My dad's best friend, same bus, same year, mostly same everything (when dad passed he was here the next day making sure I was solid). He and his wife were on I-95 last week just out side Charleston SC. He said the road felt "really rough" and then his RF tire blew (I was thinking he maybe had a goose egg, but that's not the point) The steering wheel jumped out of his hands, he had no brakes and ran into three rather large trees at 70 MPH...on curb side.

He's OK, mostly. His wife was reclined in her chair and lost her left leg below the knee in addition to a host of other injuries. She's still in SC until she can be moved home to VA.

After I spoke to him yesterday, I started thinking more about tires...and also adding impact bars to the front of the bus. I was working on tearing out the bedroom when I heard about the accident. I had the front skin off last year and realized there is really no protection whatsoever for the driver.

So, this to me anyway, has become a question of safety. An accident can happen to anyone, but as long as I'm doing this, I might as well set it up the safest possible way.

Is there a significant difference in load weight between 22 and 24? Having 22.5 now, it seems as most of you think I should keep them? I do remember mom nearly divorced dad (she was just PISSED) when he told her what the wheels cost. And when I'm finished with the re-do, she'll be getting ALL NEW tires.
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

luvrbus

The 12r x22.5 carries more weight most of the time more than a Alcoa wheel does, check the wheels for the weight limit they are not all created equal
Life is short drink the good wine first

daddysgirl

I will do that. Important info...knowing my dad, the heaviest Alcoa had, but now I want to know.
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

Dreadnought

Quote from: daddysgirl on January 24, 2017, 05:24:30 AM
I had no possible way to know when I posted this question how important and ironic it was going to be.

My dad's best friend, same bus, same year, mostly same everything (when dad passed he was here the next day making sure I was solid). He and his wife were on I-95 last week just out side Charleston SC. He said the road felt "really rough" and then his RF tire blew (I was thinking he maybe had a goose egg, but that's not the point) The steering wheel jumped out of his hands, he had no brakes and ran into three rather large trees at 70 MPH...on curb side.

He's OK, mostly. His wife was reclined in her chair and lost her left leg below the knee in addition to a host of other injuries.


That is a really really scary and sobering tale. Has got me thinking..... :(
Live Fast, Live Well, Live Free

1964 MCI MC5 8v71

B_K

Yes you are correct that in a head on collision the driver is always the first person there!
No the coaches don't have any major structural reinforcement for the driver's area.
And on top of that the reason for that is because of the design of the coaches in the first place!
Adding crash bars or whatever you can add to the front is not really going to make it any safer for you.
Because the fact that the driver sits so close to the front it doesn't matter if you add anything to the front all it's going to do is become something else coming in on the driver.

These buses are designed with safety factors considered and newer buses have the area the driver sits in re-enforced and in a crush away set up where as the driver, his seat and the immediate area around him get pushed back from the front area in an impact.
However it is not only impractical and highly dangerous to try and change the factory design in these areas. Most likely you would end up making things worse if you don't take it to an engineer who understands the original design as well as the physics of alterations.
The cost of the engineering and restructuring of the bus would be so astronomical it would simply be easier and cheaper to order a new shell that is already designed with the safety zone built in.

I admire your desire to make your bus safer, but please keep in mind the MILLIONS and MILLIONS of miles these buses travel with very few accidents and the reason that is the drivers take special care to avoid situations that will endanger their passengers and themselves.

As a side note a very close friend, and former driver of mine was driving a 2016 Prevost with less than 20,000 miles on it when he was hit head on on the drivers side by a Ford Expedition. It caused him to lose control of the bus and lay it on the passenger side in a ditch.
But he walked away with minor scrapes and bruises and a case of shock while the 23 year old mother of 3 that crossed the center line and hit him died on impact.

To this day it is unknown why she crossed the line, but the fact remains the same the shear mass of these buses gives us the drivers and the passengers the utmost advantage in most accidents.
FWIW
;D  BK  ;D

daddysgirl

It got me thinking too...and I've been on a bus, one way or another (built three of them) since I was 12. I'm almost 46 now.
I have always known and understood the significance of the responsibility that is inherent when driving a bus. Safety has always been #1. Safety for everyone on the bus (my mom and kids, which is why the SS panel and bar are still on the passenger side stepwell)...Safety and responsibility for everyone else on the road, even the idiots...Being strong enough to know that if a dumbass in a VW is more worried about being in front of you when there is NOWHERE else you can put those 40'...that you will hit him before swerving and killing the people on the left...

But it took this to happen for me to have the first thought for my safety...as a driver. If something happens to me while traveling, no one is safe. That hit me like a ton of bricks yesterday. And I'm sorry for rambling. This has really shaken me, and if this accident causes one person to consider driver safety, something good will have come from it.
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

daddysgirl

Quote from: B_K on January 24, 2017, 07:39:57 AM
Yes you are correct that in a head on collision the driver is always the first person there!
No the coaches don't have any major structural reinforcement for the driver's area.
And on top of that the reason for that is because of the design of the coaches in the first place!
Adding crash bars or whatever you can add to the front is not really going to make it any safer for you.
Because the fact that the driver sits so close to the front it doesn't matter if you add anything to the front all it's going to do is become something else coming in on the driver.

These buses are designed with safety factors considered and newer buses have the area the driver sits in re-enforced and in a crush away set up where as the driver, his seat and the immediate area around him get pushed back from the front area in an impact.
However it is not only impractical and highly dangerous to try and change the factory design in these areas. Most likely you would end up making things worse if you don't take it to an engineer who understands the original design as well as the physics of alterations.
The cost of the engineering and restructuring of the bus would be so astronomical it would simply be easier and cheaper to order a new shell that is already designed with the safety zone built in.

I admire your desire to make your bus safer, but please keep in mind the MILLIONS and MILLIONS of miles these buses travel with very few accidents and the reason that is the drivers take special care to avoid situations that will endanger their passengers and themselves.

As a side note a very close friend, and former driver of mine was driving a 2016 Prevost with less than 20,000 miles on it when he was hit head on on the drivers side by a Ford Expedition. It caused him to lose control of the bus and lay it on the passenger side in a ditch.
But he walked away with minor scrapes and bruises and a case of shock while the 23 year old mother of 3 that crossed the center line and hit him died on impact.

To this day it is unknown why she crossed the line, but the fact remains the same the shear mass of these buses gives us the drivers and the passengers the utmost advantage in most accidents.
FWIW
;D  BK  ;D
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

B_K


daddysgirl

Posted the quote first...sorry about that.

I don't want you to think I am considering anything that would NOT be designed by a mechanical AND structural engineer. They run in my family...and my friends.

And you are, as usual, correct. These coaches are built and have traveled safely millions of miles. And 99.9% of the time, in a crash with even a large car...car's gone. I just wanted you to know I'm not advocating anything that would be dangerous. I have a friend (structural engineer who has a bus) who put 2 crash bars on an older coach. One where the trim piece is, just above the bumper, and one just under the wipers. I did the CAD work for him. They wrapped around the front, were attached to the frame, and had thick rubber blocks AND special shock absorbers.
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

B_K

Not to start an argument here, but keep in mind our "motor coaches" don't have an actual frame, like that of a school bus.

And I don't doubt that your friend has added crash bars to his bus.
But I do doubt that in a crash from 70 miles per hour into a solid object such as a tree, bridge column, or even a slowed or stopped semi truck his crash bars are going to do anything besides become part of the bus that is coming toward him very very fast.

In a collision with an object with less mass I can see the benefits of such bars, however I don't see the need for them except in a serious collision as described above.

I have been in the wrecker business all my life and have seen the results of many many crashes.
And having been in the wrecker business before, during and even still now I am always particularly interested in the damage/results of crashes I see or hear of.

I have another friend who was driving a late '80's MCI 102A3 and rear ended a semi truck in a traffic jam on I-40 an did receive a broken ankle and the other leg broken between the knee and ankle.
But he lived to tell about it and even got to drive the same coach again a little over a year later after he and the coach were both returned to duty with both receiving much needed reconstruction & rehabilitation.

I'm not saying if you want to build crash bars on your bus don't do it.
I'm simply saying I don't think it's necessary and it's time and money that could be spent in much more worthwhile ways.
;D  BK  ;D

daddysgirl

I have too much respect for your opinion than to argue, and I clearly see where you're coming from...no worries.

And JFYI...the bars were designed for a head on with a noise wall at 65mph. Fortunately (for him) they tested in the world at 72mph into the back of a refrigerated truck carrying frozen Tyson chicken. He had to replace two of the little shocks.

BUT he designed them so they would specifically NOT become one more item that would wrap around him or decapitate him. He built them to prevent just that. I think because he was the engineer, he knew he could make himself safer. I'm not the engineer, but I'm certainly NOT thinking about roll bars on a 4x4 either.

But if I do anything like that (after I finish the engine, tranny, generator, water heater, plumbing electrical work, and then rebuild the interior etc...) I'll post it first.

But your valid point is well taken :)
Andrea   Richmond, VA
1974 MC8 8V71/HT740 new in 2000 and again in 2019-

TomC

When you consider that most states have a 12,000lb front axle, 20,000lb single rear axle, and 34,000lb rear tandem axle weight limit, you can go with most any truck tire you want-so long as it will support the weight of your coach. Most buses have 12R-22.5 which are naturally H rated (16 ply) at 7390lbs single, 6780lbs dual, turn 486rpm and weigh 140lbs. H rated 11R-24.5 is load rated at 7160lbs single, 6610lbs dual and weighs 131lbs. G rated 11R-24.5 is load rated at 6610lbs single and 6005lbs tandem and weighs 127lbs-which is also the the rating on the H rated 11R-22.5. G rated 11R-22.5 is 6175lbs single, 5840lbs tandem and weighs 118lbs. I could run G rated 11R-22.5, like most since my bus weighs 10,500lb front, 20,500lbs rear. But I use 11R-24.5 H rated (going to buy G rated next time) and run 90psi all around. I mention tire weight, since going from 8 12R-22.5 to 11R-22.5, you could go from a total of 1,120lbs of tire to 944lbs of tire-all of which is un-sprung weight and could mean for a slightly smoother ride. I know with big rig trucks, tire weight is important for more cargo carrying capability.
Since most bus conversions are not used for commercial passenger transportation, tire size and rating isn't legally important-only that the tires will carry the load. Good Luck, TomC
Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.