Replacing Cobra trailer wheels

Check the current tire size. If you have P155/80R-13s or even
P165/80R13s now, you can raise the height by going to a P185/80R13 by
close to 3 inches. The tires will be much cheaper than the wheels. 5
Ugly.

Not sure you want to put a bigger (round wise) tire
on the trailer. If anything, you would want to put
a wider tire on for more stability and less sway. Also,
if you go cheap, you usually always get what you pay
for. Not too sure if I would want a cheap tire on a
trailer with an expensive glider in it.....


At 14:42 11 August 2004, Samcgiltner wrote:
Check the current tire size. If you have P155/80R-13s
or even
P165/80R13s now, you can raise the height by going
to a P185/80R13 by
close to 3 inches. The tires will be much cheaper than
the wheels. 5
Ugly.

Brian: I think you misunderstood 5 ugly about tires cheaper that wheels. He
did not mean to imply that "cheap" tires should be used. Sam was in the tire
business, as well as in the glider towing business, for decades and would
never recommend anything but premium tires on the Cobra. I'm sure he was
saying that even quality tires cost less than larger wheels. I and dozens of
pilot friends have been taking 5Ugs tire recommendations for Cobras and tow
vehicles for years. He knows of what he speaks.
This is not to say that your comments are not right on.
Fly and trailer safe.
Ed Byars
"Brian Iten" wrote in message
...
Not sure you want to put a bigger (round wise) tire
on the trailer. If anything, you would want to put
a wider tire on for more stability and less sway. Also,
if you go cheap, you usually always get what you pay
for. Not too sure if I would want a cheap tire on a
trailer with an expensive glider in it.....


At 14:42 11 August 2004, Samcgiltner wrote:
Check the current tire size. If you have P155/80R-13s
or even
P165/80R13s now, you can raise the height by going
to a P185/80R13 by
close to 3 inches. The tires will be much cheaper than
the wheels. 5
Ugly.

Brian Iten wrote:
Not sure you want to put a bigger (round wise) tire
on the trailer. If anything, you would want to put
a wider tire on for more stability and less sway. Also,
if you go cheap, you usually always get what you pay
for. Not too sure if I would want a cheap tire on a
trailer with an expensive glider in it.....


At 14:42 11 August 2004, Samcgiltner wrote:

Check the current tire size. If you have P155/80R-13s
or even
P165/80R13s now, you can raise the height by going
to a P185/80R13 by
close to 3 inches. The tires will be much cheaper than
the wheels. 5
Ugly.




All depends on what you want to achieve.

Commercial vehicle tyres (i.e. made for trucks - not RV 1 tonners) have stiff
sidewalls. They also have hard compounds to handle the high loads, so may tend
to grip poorly with light load. So - less swaying but a tendency to lose
adhesion with little warning and very comprehensively. Not sure you want to go
backwards down the highway after hitting that patch of water under braking...

Normal road tyres have become progressively lower profile over the years, and
thus improve stability by reducing the ratio of sidewall to tread dimension. The
only problem is that the rims on the trailer are designed for the old 80 profile
tyres, so if you go beyond a point the (generally 5J) rim will not support the
tyre well, and it may even shed the tyre. Clearly you can't just go putting ever
wider tyres with the same circumference on the thing. In general two sizes up is
all it is advisable to go before you increase rim size. If the original was a
155x13 with an 80 profile then 175x65 is about it.

The rim is usually a standard german light car rim. Most appear to be Opel (GM)
rims. Safest bet to improve trailer dynamics is to fit similar tyres and rims on
the trailer. Match the trailer and prime mover's tyres - If your car has V rated
tyres, try to get the same tyre for your trailer, or at least the same rating.
Never fails to amaze me seeing a powerful new car with massive low profile tyres
roaring along with a trailer on 15 year old skinny low performance tyres barely
under control behind. A couple of rims from a breakers yard is not going to
break the bank.

Even if you do sort out the trailer with decent tyres, remember it does not have
the same suspension (most do not even have dampers at all) or dynamics that your
fancy uberwagen/baby hummer has. Just because your car feels rock solid does not
mean that the trailer is in it's safe envelope. Most trailers built in the
seventies and eighties are certified to 80kph/50mph - with uprated tyres and
hitches they may be fine at 120kph but not much more and not on bad surfaces, or
in windy conditions or heavy traffic.

I changed my Cobra wheels from the factory original 13s to 17 inch
wheels and tires. I made the change because of the lousy experiences I
had while towing. (with various tow vehicles) It was obviously a issue
with the weak sidewalls of the factory supplied tires. I also wanted to
increase the ground clearance at the aft end of the trailer. Initially,
going to a trailer tire with a stiffer higher sidewall using the same 13
inch wheels was my plan. That however seemed counter intuitive to my
initial desire to improve lateral stability. In my research, the bolt
pattern of 4 X 100 was found to be that commonly used on a Honda Civic
among others. It was apparent that the path of least resistance was to
find a 15 inch takeoff wheel from a Honda. That proved to be a fairly
expensive proposition and led me to a Japanese aftermarket shop located
here in Phoenix. The best Value turned out to be a closeout 17 inch
wheel and low profile tire. With that combo, the lateral contact patch
doubled, the sidewall height was halved and it is the most solid trailer
I have ever towed. Total cost out the door with tax, mounting and
balancing was $295.

Photos can be found @

http://www.asa-soaring.org/aco/pc.asp

Ed,
I did misunderstand. My fault. Granted, I have been
tempted to install some of those low profile tires
on the white Honda rims like what is on Paul Cordell's
Cobra. For some reason, the side view sure looks nice
with white rims and not too much tire showing. Just
need some blue hub caps to match the trim on the trailer
and it will be a looker.....
Brian

At 18:00 11 August 2004, Ed Byars wrote:
Brian: I think you misunderstood 5 ugly about tires
cheaper that wheels. He
did not mean to imply that 'cheap' tires should be
used. Sam was in the tire
business, as well as in the glider towing business,
for decades and would
never recommend anything but premium tires on the Cobra.
I'm sure he was
saying that even quality tires cost less than larger
wheels. I and dozens of
pilot friends have been taking 5Ugs tire recommendations
for Cobras and tow
vehicles for years. He knows of what he speaks.
This is not to say that your comments are not right
on.
Fly and trailer safe.
Ed Byars
'Brian Iten' wrote in message
...
Not sure you want to put a bigger (round wise) tire
on the trailer. If anything, you would want to put
a wider tire on for more stability and less sway.
Also,
if you go cheap, you usually always get what you pay
for. Not too sure if I would want a cheap tire on
a
trailer with an expensive glider in it.....


At 14:42 11 August 2004, Samcgiltner wrote:
Check the current tire size. If you have P155/80R-13s
or even
P165/80R13s now, you can raise the height by going
to a P185/80R13 by
close to 3 inches. The tires will be much cheaper
than
the wheels. 5
Ugly.

Sorry to have been confussing about tire replacmant for cobra
trailers.
In the past I have used a larger tire for my trailer rather than the
origional equipment tires from the trailer manufacturer. My purpose
was two fold. Increasing tire size from a P155/80R13 to a P185/80R13
will raise the clearance at axle location app. 3" The larger tire
gives me more clearance for the tail of the trailer. I would no longer
scrape the tail end when I would go over curbs, gas station entries,
exits etc. Secondly the width of the tire is also increased with the
change in tire size for a more stable ride. Bottom line is by
increasing tire size in a P Metric radial both height and width are
increased. In most cases two radials tires(I use Michelin) are "less
expensive" than two new rims and two new tires. 5 Ugly.




(samcgiltner) wrote in message . com...
Check the current tire size. If you have P155/80R-13s or even
P165/80R13s now, you can raise the height by going to a P185/80R13 by
close to 3 inches. The tires will be much cheaper than the wheels. 5
Ugly.

Hey, help me out here guys. I have one of the early
model baby Cobras, really tows well behind a F150.
I can tow across the wide open spaces out west at
McCready 5+ with it. However I just suffered a blow
out on my 165/80-13' 4-plys, and I want the beefiest
tire I can find in that size or close to it. Whadda
u guys suggest?

'Pimp my Cobra'


At 03:30 12 August 2004, Papa3 wrote:
Yo Paul,

Plus, it looks kinda slick. A boom box and some of
those fancy purple
ground lights and you'd be all set to cruise the strip
on a Saturday night.

P3


'Paul M. Cordell' wrote in message
. ..
I changed my Cobra wheels from the factory original
13s to 17 inch
wheels and tires.