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wjbusguy
Active Member

United States
24 Posts

Posted - 07/30/2013 :  1:34:08 PM  Show Profile  Visit wjbusguy's Homepage  Reply with Quote
What are you guys running for tire pressures front and rear? Almost all of our buses are 77 passenger conventional front engined buses with 11R/22.5 tires.

Mike

bus a groove
Senior Member

70 Posts

Posted - 07/30/2013 :  3:50:04 PM  Show Profile  Reply with Quote
We have Conventionals and transit style buses. All of our buses we run 100psi in the rear and 100 in the front. Its pretty standard
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partsman_ba
Administrator

United States
286 Posts

Posted - 07/30/2013 :  4:30:56 PM  Show Profile  Reply with Quote
We run 120 psi front; 80 in the rears on short buses (conventional and transit) and 100 on full sized transits.
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bwest
Administrator

United States
2319 Posts

Posted - 07/30/2013 :  5:40:32 PM  Show Profile  Reply with Quote
On the 11R tires we run 100 psi all around. We run country roads with a serious crown and I tried a lower pressure on the inside but I didn't see much of a difference in wear.

Bryan
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jadatis
New Member

1 Posts

Posted - 07/31/2013 :  07:16:41 AM  Show Profile  Visit jadatis's Homepage  Reply with Quote
Registered to this forum to give you an answer, not a busdriver.
Live in Holland and got hold of the formula that is used for tire-pressure calculation for radial tires.
What you need from tires is the "maximum load xxxx lbs AT yyy psi" written on the sidewall.
yyy is called the reference pressure and is lower then the maximum pressure.
So you are alowed to go higher then yyy . This is done for more load at lower speed.
From the bus you need the GAWR's ( Gross Axle Weight Ratings), mostly on a plate somewhere on the bus. The bus is made so that if 77 persons in it the GAWR's are not exededs, if they did it right.
Because you dont drive all the time with 77 persons, you could determine the lowest possible weight by using the empty weight and weight division, and I can put it in another spreadsheet of mine only in Dutch to see what the axle weights can get.
Also need the axle configuration like back tandem-axle and or twintwheel axle.

If you have all the data you can fill it in in my , MotorhomeRVtirepressurecalculator, or give the details here and I will do it for you. Then you can doo with using the GAWR with reserve of 0% , whenever you realy have 77 persons in it yust drive slower.
Then see if the empty weight with say 5 persons is above 85% of the weight you calculate the pressure for, this is the border below wich discomfort begins by bouncing ( determent by me trough reactions so discussable, for Traveltrailers I use 80% before screws come loose from wood.
Next link is to a map on my public map of skydrive, that belongs to my hotmail.com adress with same username as here( so combine yourselfes, spamm machines cant this way).
Download a spreadsheet first by RIGHTclicking on it then choose Download of the dropdownbox.
Dont use the top 2 possibilitys, first cant handle some things I used in the speadsheets, and second asks you to log in with your hotmail acount.
https://skydrive.live.com/?cid=a526e0eee092e6dc#cid=A526E0EEE092E6DC&id=A526E0EEE092E6DC%21793
So succes and greatings from Holland
Peter

Edited by - jadatis on 07/31/2013 07:22:14 AM
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Farmridge
Senior Member

51 Posts

Posted - 08/01/2013 :  05:13:20 AM  Show Profile  Reply with Quote
We use Firestone/Bridgestone tires, mostly 11r's and we set our air pressure according to their load data chart. The majority of ours run 85 in the front and 80 in the rear. Our tire wear is wonderful now, most are worn even and not just in the center.

http://www.trucktires.com/firestone/us_eng/load/databooks_pdf/F_MediumLightTruckDataBook.pdf

That link is for firestone. Every manufacture has one, you just have to ask. I just replace a set of rears on a rural route bus and got 98,000 miles out of them in 6 years.

You will also notice a smoother ride too.

If you can't handle the answer, don't ask the question

Edited by - Farmridge on 08/01/2013 05:14:07 AM
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wlanphier
New Member

5 Posts

Posted - 08/08/2013 :  7:56:57 PM  Show Profile  Visit wlanphier's Homepage  Reply with Quote
Not sure on the pressures but I just had a firestone tech come to my district and suggest taking the buses across the scale. He believes that our 105 psi is to high and would extend life by dropping significantly. I would contact a rep from your tire manufacturer.

Edited by - wlanphier on 08/08/2013 7:57:41 PM
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Fastback
Top Member

985 Posts

Posted - 08/09/2013 :  06:34:24 AM  Show Profile  Reply with Quote
We make sure to run 100-105 psi front in our front engine transits and have "Catseyes" on the rears of all our buses that show underinflated if we drop below 90 psi.

Why yes, the ORIGinal CHARGER is a Fastback

Edited by - Fastback on 08/09/2013 06:36:10 AM
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bbassett
New Member

7 Posts

Posted - 10/24/2013 :  07:26:12 AM  Show Profile  Visit bbassett's Homepage  Reply with Quote
quote:
Originally posted by Farmridge

We use Firestone/Bridgestone tires, mostly 11r's and we set our air pressure according to their load data chart. The majority of ours run 85 in the front and 80 in the rear. Our tire wear is wonderful now, most are worn even and not just in the center.

http://www.trucktires.com/firestone/us_eng/load/databooks_pdf/F_MediumLightTruckDataBook.pdf

That link is for firestone. Every manufacture has one, you just have to ask. I just replace a set of rears on a rural route bus and got 98,000 miles out of them in 6 years.

You will also notice a smoother ride too.

We run Bridgestone tires also but we onlt get 40,000 miles on a set on our front engine 77 passenger Internationals. What model of Bridgestone are you using?

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BJ Henderson
Advanced Member

USA
227 Posts

Posted - 10/24/2013 :  10:29:16 AM  Show Profile  Send BJ Henderson an AOL message  Reply with Quote
Each bus has a label on it for proper tire inflation. We adjust for road conditions, but very little. If the alignment is good, tire wear in minimal.

CMTT,CMAT,CMBT
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