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Author Topic: tire size  (Read 3871 times)

Offline dj

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tire size
« on: February 28, 2018, 06:26:25 PM »
Hey Guys just curious on what size tire your running...I have 11R24.5 and Im thinking going to 22.5 short rubber any thoughts?   
Thanks Doug
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Offline buswarrior

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Re: tire size
« Reply #1 on: February 28, 2018, 06:40:39 PM »
Revolutions per mile and load carrying capacity

Those are your two decisions.

Revolutions has a subtle effect on gearing, load carrying is a safety decision.

Buses used to be aimed at 495 revolutions per mile stock. The GM folks would seek out the tallest/lower rpm tireto squeak an extra couple mph outoftheir gear limited drivetrain. A heavy conversion might choose a higher number to squeak betterhill or headwind performance.

These are all subtleties, it won't change the world...

Happy coaching!
Buswarrior
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Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

Offline DoubleEagle

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Re: tire size
« Reply #2 on: February 28, 2018, 07:40:03 PM »
11R24.5 tires will cost a little more to replace, but if you want to run Alcoa's, the cost of switching to 22.5 rims will negate that. 22.5 rims are more common now, but it used to be the other way around. If excise taxes or some other factor changes the economics, things might change again. I think the bigger rims look better.
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Walter
Dayton, Ohio
1975 Silvereagle Model 05, 8V71, 4 speed Spicer
1982 Eagle Model 10, 6V92, 5 speed Spicer
1984 Eagle Model 10, 6V92 w/Jacobs, Allison HT740
1994 Eagle Model 15-45, Series 60 w/Jacobs, HT746

Offline luvrbus

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Re: tire size
« Reply #3 on: February 28, 2018, 07:44:44 PM »
What size does the chart say on the bus,Eagles were the only bus that ever ran 24.5 tires that I know of
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Life is short drink the good wine first

Offline eagle19952

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Re: tire size
« Reply #4 on: February 28, 2018, 08:19:29 PM »
the guys (engineers) who designed the bus chose what's on it for good reasons.
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Donald PH
1978 Model 05 Eagle w/Torsilastic Suspension,8V71 N, DD, Allison on 24.5's 12kw Kubota.

Offline TomC

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Re: tire size
« Reply #5 on: March 01, 2018, 07:59:22 AM »
I wouldn't change tire sizes. Both my bus and truck have 11R-24.5 rubber. As long as you can get 11R-24.5's, why change? You'll loose some top end speed.
11R-24.5 are 476rpm (revs per mile). 12R-22.5 are 485rpm. 11R-22.5 are 500rpm. 275/80R-22.4 or 295/75R-22.5 (most popular tire sizes now on big rigs) are 517rpm. Just multiply your rear end ratio by tire rpm to find out what engine speed you'll get at 60mph. Good Luck, TomC
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Tom & Donna Christman. 1985 Kenworth 40ft Super C with garage. '77 AMGeneral 10240B; 8V-71TATAIC V730.

Offline dj

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Re: tire size
« Reply #6 on: March 01, 2018, 05:12:08 PM »
Thanks for the information guys ....the data placard says 22.5  so Im thinking about going to the smaller rubber so if I take it up to the mountains for skiing ill at least have room to throw tire chains on if i need to
thanks again for the info    Doug
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Offline Scott & Heather

  • Scott & Heather's buses: MCI-9 & MCI-102
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Re: tire size
« Reply #7 on: March 02, 2018, 04:12:40 AM »
So you’re willing to replace all your rims? I love my 24.5’s:




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Scott & Heather
1984 MCI 9 6V92-turbo with 9 inch roof raise (SOLD)
1992 MCI 102C3 8v92-turbo with 8 inch roof raise CURRENT HOME
Click link for 900 photos of our 1st bus conversion:
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