20'' 22.5'' 24.5'' tire size / ... Log Out | Topics | Search
Moderators | Edit Profile

BNO BBS - BNO's Bulletin Board System » THE ARCHIVES » Year 2004 » June 2004 » 20'' 22.5'' 24.5'' tire size / swap question « Previous Next »

Author Message
scoolbusnut (216.239.160.71)

Rating: N/A
Votes: 0 (Vote!)

Posted on Monday, June 21, 2004 - 10:23 pm:   

My bus currently has 20" tires. I have heard that it is an odball size compared to the vast majority of the trucks and buses on the road, therefore a tire repair could become a big issue.

I recall reading here (?) that going from 20 inch to 22.5 inch will not affect the gear ratio enough to cause any noticeable difference at highway speeds. (?)

What about going from 20" to 24.5"? ...Too big of a jump up in size?

I don't need to gear it up... a little would not hurt. I have highway gears already.

How would I go about finding out if it will work?

Anybody know what the O.D. of a 24.5" is?

Thankyou,
Mark
75 gillig636D
sam (69.11.142.105)

Rating: N/A
Votes: 0 (Vote!)

Posted on Monday, June 21, 2004 - 10:33 pm:   

the height of a 11-24.5 is 43 inches a 11-22.5 is about 40-41 inches and a 12-22.5 is 42 inches I just put a set of 11-24.5 on the front of our MCI 8
sam
RJ Long (67.181.211.253)

Rating: N/A
Votes: 0 (Vote!)

Posted on Monday, June 21, 2004 - 11:08 pm:   

Marc -

Time to do a little homework. . .

You need to log on to any one of the major tire manufacturer's websites, and start looking at their truck tire size charts. For example, www.trucktires.com will take you to the Bridgestone/Firestone site.

Once there, look for an "all-position" tire in the sizes you're interested in, starting with your original 20", as well as 22.5" and 24.5". In the specs sections, you'll find such things as load range, diameter, revs per mile, max rated speed, etc.

After you've found this info, open an additional window (Ctrl+n), and plug this URL into the address:

http://home1.gte.net/res07rfl/4106/calcmph.htm

Now, play to your heart's content, as you plug various tire diameters into the equation Daris has set up, to really see what the results would be by experimenting with different tire sizes.

Have fun!!

HTH,

RJ
PD4106-2784
Fresno CA
Henry R. Bergman, Jr. (Henryofcj) (209.210.116.194)

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, June 22, 2004 - 3:21 pm:   

Yeah, ditto. Plus one might look hard and long at the existing wheel wells and see if the taller tire will fit.

This means full lock to lock front wheel travel when the suspension is compressed, plus enough room on the rears to mount...

...tire chains should they ever be needed. Sometimes taller tires cause big problems. Good luck.
Johnny (63.159.217.171)

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, June 22, 2004 - 9:05 pm:   

A 10.00-20 & an 11R22.5 are the same height (+/- half an inch). The same applies to an 11.00-20 & a 12R22.5 tire.

Be aware the 12R22.5 isd also an oddball.

IIRC, a 315/80R22.5 is also equivilant to a 12R22.5--I see plenty of these now.

10.00R20's are available--the wrecker I drive at work runs them (Bandag traction tires in back, highway-rib G159's in front). For drives, I suggest Bandags. Steers, some school bus fleets will have take-offs (frequently high-end tires--here, they run Goodyears & Michelins). Long-noses ran 20's until pretty recently, but be careful not to get bias-plies.

I do suggest carrying a spare tube.
LHD (216.58.209.129)

Rating: N/A
Votes: 0 (Vote!)

Posted on Tuesday, June 22, 2004 - 11:55 pm:   

rim size has nothing to do with height of tire you can buy 24.5 that is shorter than 22.5
LHD (216.58.209.129)

Rating: N/A
Votes: 0 (Vote!)

Posted on Wednesday, June 23, 2004 - 12:02 am:   

20 is tube type you dont want 22.5 uses differnt rim 24.5 is different again
John the busboy (12.72.235.58)

Rating: N/A
Votes: 0 (Vote!)

Posted on Wednesday, June 23, 2004 - 4:20 am:   

We went from a 9R20 to an 11R22.5. The front tires barely fit. Had to grind down a couple screws that were sticking out from the mud flaps.

Our road speed went from 53 or 54 mph to 57 mph. 53 really sucks, but 57 you can live with....at least we did, for a while.

John the busboy
84 BB/GMC
Vern1 (63.164.202.130)

Rating: N/A
Votes: 0 (Vote!)

Posted on Wednesday, June 23, 2004 - 7:41 am:   

Greetings,
Assuming by your user name that you are using a Skoolie with 20" splits and tubes now?
Go here:
http://www.hdpsales.com/accuriderims.htm
These rims will fit right on your Dayton spokesand allow you to run radials.
On my Skoolie, F130391225 is the part number that crosses over from the 10.00x20s TIRES I have on there now. I think the split rims are 7" wide, but don't remember......ah, senior moment....
I already have the new rims, just waiting for the money for new tires....
I will probably run new steers and pulls for the rear. They told me at the truck tire shop that you could interchange these with the stock splits, but caution on running one radial and one bias ply on the same side on back and also said that they were the same size in overall height.
I want to get the new tires, then use one or two of the splits for a spare until I can afford another new setup for a spare.
Hope this helps!
Here is a link to my Skoolie, but it still has the stock splits on there right now.
www.pettypb.com/bus
Cheers,
Joe Petty

Add Your Message Here
Posting is currently disabled in this topic. Contact your discussion moderator for more information.

Topics | Last Day | Last Week | Tree View | Search | Help/Instructions | Program Credits Administration