|
|
05-17-2009, 05:05 AM
|
#1
|
Gunter
1966 24' Tradewind
1984 34.5' Airstream 345
Greenville
, Ohio
Join Date: Mar 2006
Posts: 347
|
Classic Motorhome Tires
Has anyone converted from their original size 8R19.5 to 225/70R19.5 Tires. I am particularly concerned with the clearance between the tag axle tire and the inner fender since it is minimal now with the original size tire. I believe there is sufficient clearance between the duals.
__________________
Gunter
2000 Land Yacht XL 355
|
|
|
05-17-2009, 10:44 PM
|
#2
|
Rivet Master
1989 34.5' Airstream 345
Silverton
, Colorado
Join Date: Oct 2003
Posts: 2,102
|
Gunter,
Nope...I run Michelins...tires are more important than the engine, to me...can always find a 454, but replacing a 345 is getting harder to do.
mike
__________________
Michael & Tracy
1989 345 Motorhome
CHARTER MEMBERS: FOUR CORNERS UNIT, AND PROUD OF IT!!!
We live for the moment, 'cause when you get there, it's gone...
|
|
|
05-18-2009, 03:14 PM
|
#3
|
Gunter
1966 24' Tradewind
1984 34.5' Airstream 345
Greenville
, Ohio
Join Date: Mar 2006
Posts: 347
|
What I want to put on are Michelin XZE, but I am concerned about the clearance since these are 8.9 wide.
__________________
Gunter
2000 Land Yacht XL 355
|
|
|
05-18-2009, 04:38 PM
|
#4
|
Rivet Master
1989 34.5' Airstream 345
Silverton
, Colorado
Join Date: Oct 2003
Posts: 2,102
|
Not sure about the extra inch, if the front bonnet has ever been compromised(read hit something hard enough to bend it...we have 8.0 XZA 19.5>...since I don't do my tires on the MH, I don't know about clearance, but someone out there HAS to have thought about this before. I would want to know a couple or so things before I jumped...
Will the suspension be affected? Will this have any effect on the airbags(I know, part of the suspension, but maybe another can of worms)? What will the effect on the steering be?
I'm curious about your plan to go a little bigger on the tires...is there something you have heard, or is this a personal knowledge kinda thing?
m
__________________
Michael & Tracy
1989 345 Motorhome
CHARTER MEMBERS: FOUR CORNERS UNIT, AND PROUD OF IT!!!
We live for the moment, 'cause when you get there, it's gone...
|
|
|
05-19-2009, 11:33 AM
|
#5
|
Rivet Master
1974 20' Argosy 20
Richmond
, Kentucky
Join Date: Jan 2003
Posts: 9,115
|
Quote:
Originally Posted by gunner
Has anyone converted from their original size 8R19.5 to 225/70R19.5 Tires. I am particularly concerned with the clearance between the tag axle tire and the inner fender since it is minimal now with the original size tire. I believe there is sufficient clearance between the duals.
|
Gunter, I'm curious as to why you want to change from the 8R19.5 to the 225/70R19.5 tires. What are the advantages and disadvantages?
Brad
__________________
Air forums # 1674
1974 20' Argosy Motor Home
1975 24' Argosy Motor Home
1974 31' Excella trailer (parting out, as of 4/1/2015 I have wheels & windows left to sell)
|
|
|
05-19-2009, 01:41 PM
|
#6
|
Rivet Master
Commercial Member
2019 27' Tommy Bahama
London
, Ontario
Join Date: Aug 2007
Posts: 1,343
|
Hi Gunter
What we have been doing on Classic Motorhomes for the last 15 years or so is running the 225/70 19.5 tires on the front but staying with the 8.00 19.5's on the rear. The reason for this is the 225/70's have a more precise steering feel.
On the rear the 8.00's ride smoother and because of their larger diameter you don't increase the engine RPM.
Andrew T
__________________
Andrew Thomson London, Ontario
"One test is worth a thousand expert opinions." Tex Johnston, Boeing 707 test pilot
|
|
|
05-19-2009, 08:30 PM
|
#7
|
Gunter
1966 24' Tradewind
1984 34.5' Airstream 345
Greenville
, Ohio
Join Date: Mar 2006
Posts: 347
|
I have new Bridgestone 8R19.5 on the front, a friend of mine gave me 7 new Michelin 225/70R19.5 that I want to put on the rear and the spare when my current tires either wear out or the sidewalls start to deteriorate. The only concern I have is the tag axle tires due to the clearance to the inner fender.
__________________
Gunter
2000 Land Yacht XL 355
|
|
|
05-20-2009, 06:21 AM
|
#8
|
Rivet Master
Commercial Member
2019 27' Tommy Bahama
London
, Ontario
Join Date: Aug 2007
Posts: 1,343
|
Hi Gunter
If you use the 225/70's on the duals you will increase your engine RPM by 5% or 150 RPM at 60 MPH. I always felt the 454 was spinning plenty fast on the pre overdrive coaches.
As well the 225 has less sidwall roll and more traction so it will put more pressure on the tag axle bearings and the axle itself. The tag axle bearings do not have a lot of margin for additonal load.
The shorter sidewall also rides firmer so you will get more pounding through the duals into the body of the coach.
They may work ok but those are the reasons we only use them on the steering axle.
Andrew T
__________________
Andrew Thomson London, Ontario
"One test is worth a thousand expert opinions." Tex Johnston, Boeing 707 test pilot
|
|
|
05-20-2009, 08:51 AM
|
#9
|
Rivet Master
Currently Looking...
1984 31' Airstream310
Ajo
, Arizona
Join Date: Mar 2007
Posts: 7,649
|
Stick with the 8R19.5, I've been running Goodyear G647 RSS tires for years and get great performance out of them.
|
|
|
05-20-2009, 12:52 PM
|
#10
|
Rivet Master
1984 31' Airstream310
Dunsmuir
, California
Join Date: May 2004
Posts: 1,336
|
Quote:
Originally Posted by Andrew T
Hi Gunter
If you use the 225/70's on the duals you will increase your engine RPM by 5% or 150 RPM at 60 MPH. I always felt the 454 was spinning plenty fast on the pre overdrive coaches.
As well the 225 has less sidwall roll and more traction so it will put more pressure on the tag axle bearings and the axle itself. The tag axle bearings do not have a lot of margin for additonal load.
The shorter sidewall also rides firmer so you will get more pounding through the duals into the body of the coach.
They may work ok but those are the reasons we only use them on the steering axle.
Andrew T
|
I run Michelin 225's on the front and 8R's on the back. Thus I don't increase RPM but do get a wider stance in front. I carry an 8R spare.
So far, so good.
The Michelins made a huge difference in the ride.
Oops, Andrew I didn't see your earlier post on this same configuration, oh well, great minds etc.
__________________
If you want others to be happy, practice compassion.
If you want to be happy, practice compassion - The Dalai Lama
1984 310 Limited Motorhome
Courtesy Parking (W/S/E/Wi-Fi) on I-5 in Northern California, 70 miles from Oregon border
|
|
|
05-20-2009, 03:12 PM
|
#11
|
Gunter
1966 24' Tradewind
1984 34.5' Airstream 345
Greenville
, Ohio
Join Date: Mar 2006
Posts: 347
|
It is hard to turn down new tires at no charge.
__________________
Gunter
2000 Land Yacht XL 355
|
|
|
05-20-2009, 09:02 PM
|
#12
|
4 Rivet Member
2005 25' International CCD
Leesburg
, Georgia
Join Date: Sep 2005
Posts: 316
|
Tnstaafl
Quote:
Originally Posted by gunner
It is hard to turn down new tires at no charge.
|
- there's no such thing as a free lunch!
I have 8r19.5 Dynatracs on my front wheels - last digits on the dot #'s are 02207 which I assume means manufactured in February, 2007?
However on the remaining 6 I have the Michelin 8r19.5's, but with dot #'s ending in 0300 and 0700!
I know they need replacing, but what with, Dynatracs or Michelins?
On size, the consensus appears to be, keep the 8r19.5's for the duals and tag and something with less diameter and more width up front like 225/70R19.5
__________________
Andy
|
|
|
05-29-2009, 03:23 PM
|
#13
|
4 Rivet Member
1983 31' Airstream310
Iwerne Minster
, Dorset. UK
Join Date: Aug 2005
Posts: 274
|
This is strange. I recently had a 345 in for UK preparation, and that had the larger tyres all round. After my 310 with the standard tyres the cornering was phenomenal, despite the front steering and suspension being totally shot away. I replaced the bell cranks, suspension arms and others, and the road holding was far superior to my 310.
I take the point that these bigger tyres do run the engine faster due to the smaller radius, hence my wishes to GV overdrive - OR even fit the 4 speed gear box. Has any one any thoughts on that?
__________________
Chuck
Dorset UK
Don't take life so seriously.... it is not permanent!
|
|
|
09-13-2009, 08:23 AM
|
#14
|
Gunter
1966 24' Tradewind
1984 34.5' Airstream 345
Greenville
, Ohio
Join Date: Mar 2006
Posts: 347
|
I am asking for your input in regard to this possibility. Since I have limited clearance between the inner fender with the current 8R19.5 Tires on the Tag Axle, I am thinking of installing the 225/70R19.5 on the Front and the other four on the drive axle and leaving the 8R19.5 on the Tag. The difference in diameter between the two tires is 1" or between the center of the tire and bottom .5 inches. I would believe there is that much difference in road surface and this wouldn't be a issue. This way I would have the stability of wider tires on the front and drive axle and still maintain the original clearance between the inner fender and tire on the Tag axle. The only other alternative is to machine a .5" aluminum spacer between the wheel and drum to achieve additional clearance.
__________________
Gunter
2000 Land Yacht XL 355
|
|
|
09-13-2009, 08:30 AM
|
#15
|
Rivet Master
Currently Looking...
1984 31' Airstream310
Ajo
, Arizona
Join Date: Mar 2007
Posts: 7,649
|
Maybe someone knows more, but my mechanic, who maintains the Fire Dept. rigs, told me the wider the tire, the better the possiblility of wheel bearing failure.
|
|
|
09-13-2009, 09:34 AM
|
#16
|
Rivet Master
2011 34' Classic
Westchester Cty.NY
, / Miami FL
Join Date: Jul 2007
Posts: 3,122
|
if you decide to do that change i'd be curious to see weigh slips before and after. in theory, wouldn't the axle with the taller tires carry more of a load?
__________________
Ricky
2012 F150 Super Crew 5-1/2' bed Ecoboost 4x4 3.73 elec. lock diff. Propride hitch
give life. kidney & pancreas transplant 9/9/06
Ingrid-my unofficial '"World's Oldest Streamer" 1909-2008 R.I.P.
|
|
|
09-13-2009, 12:28 PM
|
#17
|
Gunter
1966 24' Tradewind
1984 34.5' Airstream 345
Greenville
, Ohio
Join Date: Mar 2006
Posts: 347
|
I believe the Tag axle is more forgiving by that I mean that it moves up and down with less pressure than the drive wheel axle. I did have the concern that I wouldn't have as much of a down force on the drive wheels and could affect traction.
__________________
Gunter
2000 Land Yacht XL 355
|
|
|
09-13-2009, 07:49 PM
|
#18
|
Rivet Master
1989 34.5' Airstream 345
Silverton
, Colorado
Join Date: Oct 2003
Posts: 2,102
|
I have noticed that the tag axle tires leave rubber tread marks when executing a sharp turn in a parking lot...m
__________________
Michael & Tracy
1989 345 Motorhome
CHARTER MEMBERS: FOUR CORNERS UNIT, AND PROUD OF IT!!!
We live for the moment, 'cause when you get there, it's gone...
|
|
|
09-14-2009, 10:34 PM
|
#19
|
Rivet Master
2006 28' Safari SE
Currently Looking...
Colorado Springs
, Colorado
Join Date: Jun 2003
Posts: 703
|
Mike,
I think the tread marks may be unique to your driving style...
-Ken
__________________
4CU Charter Member
|
|
|
09-15-2009, 05:24 PM
|
#20
|
4 Rivet Member
2005 25' International CCD
Leesburg
, Georgia
Join Date: Sep 2005
Posts: 316
|
My tags leave a bunch of marks on sharp turns too, like exiting our drive way.
Could it be to do with age, or something else? It would be quite a site seeing one of our classics burning donuts in the car park!
__________________
Andy
|
|
|
|
|
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|