Wheel Cut Degrees

[tireman9]

As I read various write-ups on new motor homes I many times see reference to "xx degrees wheel cut". While I understand this has some impact on the vehicle turning radius this number seems to be of little value when trying to understand the ability of MH-A to turn around in a circle that is larger or smaller than MH-B.

There are many other factors which have a more significant impact on turning radius than the number of degrees the front wheels can be turned.

Isn't this just some marketing hype?

[wolfe10]

Interesting.

Wheelbase and front wheel cut angles are the two major factors in turning radius (at least at curb level).

Overhangs come into play in looking at turning radius if higher than curb level is being discussed.

Brett

[Guest BillAdams]

I don't believe that this is hype. 2 coaches with the same wheel base and the same "wheel cut" would turn in the same sized circle. Understanding that, if one coach has a tighter cut it would "cut" a tighter circle. As long as you are comparing apples to apples then the differences are important. A longer wheel base will give you a better ride. A longer rear overhang will effect what you might hit when you turn but not the actual turning radius. Be sure you are comparing the correct parameters and the information presented is of great value.

[hermanmullins]

One other factor is rear axles. Single or double. Will tag axle rise to help turning. I look forward to a lot of the answers to this question.

Regards

[wolfe10]

One other factor is rear axles. Single or double. Will tag axle rise to help turning. I look forward to a lot of the answers to this question.

Regards

Yes, the majority of tag axles raise for tight cornering. If so they use the front/drive axle as the operative wheelbase for cornering. If they don't raise, they would scrub badly on tight cornering, and may therefore affect turning radius.

Brett

[tireman9]

I completely agree that there are other factors that contribute to turning radius.

What I do not understand is why magazine reviewers provide this relatively meaningless number when the number I would like to know is the actual turning radius. This is an easy measurement to get, even in a dealer parking lot.

Another contributing factor is the cornering coeficient of the tires. This is the side force generated as a % of load at given turning angle. I see no way for a reader to include this information in the buying decision and of course no way for the reviewer to get the number.

Given the technical shortcommings in magazine "reviews" this media hype is just wasted ink in my opinion.

I could come up with a list of dozens of "measurements" which might make a "review" I could write sound very detailed but in reality provide no meaningful data that would allow a more informed purchase decision to someone trying to decide which RV to buy.

In my opinion, RV magazines need to do a much better job of presenting real reviews rather than "puff pieces" which many times read more like press releases. Reviewers need to take a look at the work done by car magazine writers to see how real, meaningful information can be presented.

How should I compare vehicle A that has a turning radius of 75'-6"

than... than Wheel cut is 55 degrees, wheel base if 30'-10", Cornering coefficient is 0.234 at 2 degrees slip, and there is a tag axle which carries 9,850#

[harrysusa]

I agree, the wheel cut degree is meaningless hype. Just tell me what the turning diameter is for the particular coach that is being tested.

The wheel cut degree will probably be the same for a 34' or a 40' coach (on the same chassis), but the turning diameter will certainly be different.

Harry Salit

[Garyr]

I've had both 25-30 degree wheel cut and the new Freightliner chassis with 55-60 degree cut I much prefer the new chassis. I can't turn on a dime but when you are getting into a tight RV site there are not the back and forward several times like the old chassis. Turning corners are now much easier now.

Gary