Community Forums

R1Kirby · 05-05-2009, 07:04 AM

A service man told me yesterday that radial tires can cause a number of control (swaying, rocking, wandering, etc..) issues with a class c motorhome. I should be running a bias tire. Has anyone ever heard of this? I have Lt 215/85R16 Load Range E.

TXiceman · 05-05-2009, 07:14 AM

R1Kirby,

I believe this is an older urban legend. If you have the radials aired properly, it should not be a problem. In general class C's tend to be top heavy and this causes some rolling side to side regargless of the tires. To control the roll, it usually takes HD shocks and heavy anti-roll bars. Also, the laod range E tires have a pretty stiff sidewall.

I'd rather have the radial tire on the vehicle. What brand tires is he basing this story?

Route 66 · 05-05-2009, 07:17 AM

I agree that radials are OK. Just about every tire is radial now.

RustyJC · 05-05-2009, 07:21 AM

We hear this now and then on heavy TT and 5th wheel trailers as well. Unfortunately, technology advances but some individuals don't. Radial tire technology just about owns the marketplace for many good reasons.

Rusty

CD · 05-05-2009, 07:32 AM

R1Kirby
I would recomend weighing your rig fully loaded and compare to the tire load & pressure rating & weigh each axle or better yet each corner. It's been my oppinion that most RVs have just enough tire to carry the GVW & thats all. If your wheels will handle them I would consider 235s or bigger. I believe your handling would be much better. That has been my experience.

Ray,IN · 05-05-2009, 09:19 PM

http://media.wiley.com/product_data/...0471354619.pdf
May explain why that service man said what he did. Bias-ply tires do not "roll or squirm" as much as radial tires- is the short story.

Tom and Patty · 05-05-2009, 10:54 PM

I guarantee if you put a set of bias ply on your MH all the way around, the front tires would track imperfections on the road like a train on rails

. You wouldn't drive 100 miles

.

You could put them only on the rear, but that is another story

BTW there is an error in the first equation on page 25, thereby refuting the "bias is better at squirm theory"

RedneckExpress · 05-12-2009, 02:39 PM

Hmmm.... Dunno, been looking at a set of 16.5x12 Load Range G Bias plys for the rear myself.

CD · 05-12-2009, 07:04 PM

RedneckExpress
I suggest you research this real good. Back in the early 70's I owned (with a partner) a tire shop. People that mixed Radials & biased tires were having handling problems. I don 't know if that has changed since.

TXiceman · 05-13-2009, 05:42 AM

I believe the current thoughts are not to mix radial and bias ply on the same axle. Personally, I would not mix them at all.

Ken

CD · 05-13-2009, 08:02 AM

Radials were new then and if I remember right, people woud buy radials in the summer and then put on their bias ply snow tires for the winter, then the trouble would start. Some would have lots of trouble and others none.

RustyJC · 05-13-2009, 08:32 AM

From Goodyear's website:

Quote:

When buying just two new tires, should they be put on the front or rear?

When radial tires are used with bias or bias belted tires on the same car, the radials must always be placed on the rear axle. Never mix radial and bias-ply tires on the same axle. When you select a pair of replacement tires in the same size and construction as those on the car, we recommend you put them on the rear axle. A single new tire should be paired on the rear axle with the tire having the most tread depth of the other three.

Rusty

RedneckExpress · 05-14-2009, 10:40 AM

Quote:

Originally Posted by CD

RedneckExpress
I suggest you research this real good. Back in the early 70's I owned (with a partner) a tire shop. People that mixed Radials & biased tires were having handling problems. I don 't know if that has changed since.

Owned a truck that had both once before in the family. It had bias ply tube tires on the rear and radial tubeless on the front. Other than the tires getting a flat spot in them from sitting for long periods of time, never had any handling problems.

I'm more likely to encounter issues from the foot-wide width of the 16.5x12 tires on the back catching the ruts.

These are not the same brand (McCreary/STA vs Denman), but similar styling to the Denman 14 ply tires I was looking at.

If I could have found a pair of Radial 16.5x12 Load Range F or Load Range G tires, I would have gone with them.

I've found plenty of E range, which defeats the purpose of the bigger rim. I've also not found a good deal on the E range. I got quoted for $200 a tire for the Bias G range which included the mounting from a local tire shop that's been in business since 1946.