large single tires instead of duals

phil4501 · June 21, 2006, 11:06:57 PM

Scenicruiser has dual wheels on the tags. I think the other buses mentioned do as well

tucsontattoo · June 22, 2006, 06:50:37 AM

O.K. I get it ,wondered how you would get that great big tire in that littli shallow tag axel wheelwell.

TomC · June 22, 2006, 07:52:35 AM

Correct. Drive axle has 4 tires and the tag has 2 tires. 4501, Crown and Gillig schooly 40ft'rs have a true truck like tandem using 8 tires. Good Luck, TomC

Bosshosssport96 · June 22, 2006, 08:24:43 AM

About 4 months ago,I went down to a friend of mine tire shop to talk to him about putting these super singles on my Scenicruiser,taking these low profile tires of numerious brand names and putting them next to a 11R22.5/12R22.5 set-up,their was a big difference in height.This in itself creates a problem for me,in that the bus would sit lower,and the lower profile look would of look kind of funny in the large well aera of the Scenic.I didn't want my Scenic sitting any closer to the ground then it already was.Anybody wanting to go to this set-up will be spending big bucks,especially on the Alcoas.The cost even tho high was not the deciding factor for me,it was the height issue,which also means their would of been some leveling valves to adjust in the rear to bring it level again(not a problem tho),just my .02 worth.....Frank 4501-082

DrivingMissLazy · June 22, 2006, 10:38:05 AM

Are you saying that the super singles are not as tall as the 11R22.5 tire?
Richard

Quote from: Bosshosssport96 on June 22, 2006, 08:24:43 AM
About 4 months ago,I went down to a friend of mine tire shop to talk to him about putting these super singles on my Scenicruiser,taking these low profile tires of numerious brand names and putting them next to a 11R22.5/12R22.5 set-up,their was a big difference in height.This in itself creates a problem for me,in that the bus would sit lower,and the lower profile look would of look kind of funny in the large well aera of the Scenic.I didn't want my Scenic sitting any closer to the ground then it already was.Anybody wanting to go to this set-up will be spending big bucks,especially on the Alcoas.The cost even tho high was not the deciding factor for me,it was the height issue,which also means their would of been some leveling valves to adjust in the rear to bring it level again(not a problem tho),just my .02 worth.....Frank 4501-082

WEC4104 · June 22, 2006, 11:10:04 AM

Boss, you got me wondering with your comments concerning the tire height. From your description, it sounds like maybe you took samples of the super singles (unmounted, uninflated) and placed them up against the tires on your coach for comparison. Noticing a "big difference in height", would mean the overall tire diameter would have to be signifcantly smaller.

Aside from the appearance of having a Scenic "lowrider", and potential ground clearance issues, I began to wonder about other concerns. Simple geometry says that a smaller diameter means a smaller circumference, and more revolutions per mile. Could a switch to the super singles really require an axle ratio change? I wouldn't think the tire manufacturers would make it that difficult. So I popped over to the Michelin website to check things out ...

A traditional 11R22.5 is typically 501 - 503 revs/mile
A traditional 12R22.5 is about 486 revs/mile
A traditional 11R24.5 is typically 476-479 revs / mile

compared to the four models of Michelin X-Ones I found

X-One XDA 518 revs/mile
X-One XDA HT Plus 493 revs/mile (in the larger size)
X-One XZU S 493 revs/mile

So that means the HT Plus and the XZU should actually be slightly taller than the normal 11R22.5. Compared to the traditional 12R22.5 they should be just a bit smaller. (about 2.3 inches in circumference, or just about 3/4 of an inch shorter). I'll skip the comparison to the 11R24.5 because of the significant rev/mile spread.

Goodyear's website had super singles with even larger diameters (less revs/mile)

TomC · June 22, 2006, 12:49:27 PM

When going to other tire manufacturers other than Michelin, you have to watch to see if you are mixing up the old fashion super singles (385/65, 425/65, 445/65-22.5) that are only rated to 65mph with the new X-ones that are 445/50-22.5 (like the standard low profile 295/75 or 275/80-22.5) or the 455/55-22.5 that is like the 11-22.5 that are rated at 75mph. According to Michelin, the DO allow using the X-Ones on buses with tags. Good Luck, TomC

Bosshosssport96 · June 22, 2006, 05:57:29 PM

I have 12R22.5 on my Scenicruiser,when I went down to my friends tire shop,he rolled out all the different brands(no Goodyear tho,they were having problems of some sort with theirs).Putting these tires next to new 11R22.5/12r22.5 tires,their was roughly a 3'' difference in height,or roughly 1.5"" lower if mounted on the vehicle,this didn't sit well with me.It wouldn't of looked right with the big 12R22.5 on the front.Scenicruisers have some big rear wheel wells.

I remember shortly after when I was fueling up at a gas station,I pulled up next to a fuel truck (truck and trailer) that had the super singles,it looked like it had tonka toy tires on it compared to my 12R22.5.The tires did look good on the set-up tho,partly due to no wheel wells around them.If they were a bit smaller,you could put them on a light duty truck.....*smiling*....Frank 4501-082

TomC · June 22, 2006, 06:03:44 PM

Frank-personally, I switched my bus from the 12R-22.5 to 11R-24.5, since the 24.5's are more readily available compared to the 12R's, plus they are a bit taller (43.5" compared to 42.6" or 12R has 486rpm and the 11R has 478rpm) I figure anything that might give better fuel mileage is worth a look. If you run the 16 ply 11R-24.5, the front axle would be rated at 14,320lb compared to the 12R-22.5's at 14,780lb-so you see, very close. Good Luck,TomC