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Topic: Turning Radius - How big my driveway? (Read 590 times) previous topic - next topic

Turning Radius - How big my driveway?

Quoting from Barry Beam's Specifications page:

Coach length/wheel base/ approximate turning radius for beam axle coaches:
This should apply to both the U270/295/320 and the Nimbus/Phenix beam axle coaches.

34'  204" wb                                      35'9" curb to curb 37'8" wall to wall
36'  228" wb                                      39'3" curb to curb 41'4" wall to wall
38' no tag  252" wb                            39'7" curb to curb 41'9" wall to wall
38' tag  228" to drive /278" to tag wb 39'3" curb to curb 41'4" wall to wall
40' no tag  276" wb                          44'3" curb to curb 46'6" wall to wall
40' tag  252" to drive /302" to tag wb 39'7" curb to curb 41'9" wall to wall
42' tag  276" to drive /326" to tag wb 46'5" curb to curb 48'9" wall to wall

(I'm including lengths other than 36' as an aid to other folks :D )

Background
I have managed to make 90 deg turns into storage stalls, through gates, and into camp sites. As yet I have felt it has been a trying, catch by catch occurrence, usually requiring back and fill operations .
(I can feel for the poster who has a 9'6" door!!)

Geometry
Lets suppose I want to make a 90 degree turn into a garage
Lets say my left mirror , I have changed this to the left rear wheel, is at point x=0, y=0
Using the above tabulated turning radius of 41'4" wall to wall (lets use 42")

My Question(s)
Assuming I could have my wheel hard over at point (0,0) would I be tangent to a circle of radius 21' at point (21,21)?
(there is a significant problem here :-X  help me out...)
Or, alternatively, if the street was 21' from the garage and I started with my rear wheels 21 ' back from the drive, could I get into the garage in one maneuver?
(note the rear wheel issue - where else might the pivot be?)

I'm sure if I went to driving school this would all become clear but we are in the throes of unpacking and I wanted to escape...



Elliott & Mary Bray
ex. 1996 36' U295 - Build 4879
ex. 2018 Coachmen Leprechaun 319MB
 

Re: Turning Radius - How big my driveway?

Reply #1
How wide is your driveway?
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Turning Radius - How big my driveway?

Reply #2
My 276" WB non tag 40' takes much more space than shown bumper to bumper.  70'?  Is my stops turned out that far or is the chart wrong?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Turning Radius - How big my driveway?

Reply #3
Bob,

You will have to tell us.  Have you checked your cut angles/stops properly set and proper gap between mechanical stops(adjusted on the steering knuckle-- stop) and hydraulic stops (adjusted on Sheppard box)?
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: Turning Radius - How big my driveway?

Reply #4
Bob,

You will have to tell us.  Have you checked your cut angles/stops properly set and proper gap between mechanical stops(adjusted on the steering knuckle-- stop) and hydraulic stops (adjusted on Sheppard box)?

Or someone else can make a circle and roughly walk off the diameter?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Turning Radius - How big my driveway?

Reply #5
Find a big parking lot at night, mark where u start and turn 180 deg. Get out and measure and you will know where you stand.  If you can't repeat factory settings it's time to look for something worn or out of adjustment
Steve DeLange
2005 U320T 40'
Pearland, Texas

Re: Turning Radius - How big my driveway?

Reply #6
Find a big parking lot at night, mark where u start and turn 180 deg. Get out and measure and you will know where you stand.  If you can't repeat factory settings it's time to look for something worn or out of adjustment

Hard to make the front wheels go sideways.  31' WB.  Only moves forward ten feet in a u turn?  Love to find mine that mis adjusted btw.  Seems like a 252" WB would put an incredible side load on the tag? 

55 degrees was the bomb as far as side cut. 

Driven countless 40's and either I' m crazy or the figures are way off. 

Please tell me I'm wrong?


Bob
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

 

Re: Turning Radius - How big my driveway?

Reply #7
Or someone else can make a circle and roughly walk off the diameter?


We have had a number of blown steering box seals because of improper steering box limit sets.  Not sure that geometry can tell whether you have 1/8" clearance between where the steering box hydraulic limit is set and the physical stop. 

Restate:  I KNOW it can't be done.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020