Trailer follies

FYI...

The Cobra trailer for one of the two CAP ASK-21's had developed a
problem with the left tire and had a tendency to sway. The tire was
deteriorating rapidly, wearing on one side with severe cupping. The
tires were relatively new trailer rated bias ply. Theories ranged
from a bent axle to a bad tire with misaligned belting.

A trip to a professional trailer shop uncovered the real cause -
jammed left brake. The Cobra's surge brakes are purely mechanical
with a push-pull rod from the hitch to near the axle where two cables
run to the drum brakes. The left cable had become jammed with dirt
and wasn't releasing the brake causing it to drag until it could
barely roll. The asymmetrical braking was contributing to the
swaying.

There are no dust boots on the cable housing to keep dirt out so this
is likely to be a recurring problem.

All the towing vehicles have electric brake controllers installed so
I'm campaigning for converting the Cobra trailers to electric brakes.

I'm campaigning for converting the Cobra trailers to electric brakes.

+1 -and let me help you get it started...

Dear Mr Spindelberger, surge brakes suck. I'd rather have no brakes
than deal with the large range of well known and predictable nonsense
that accompanies that outdated overpriced unreliable system. Cobra
should at least offer electrics as a stock option, or at least without
any brakes so we can convert them ourselves with the extra 2 grand
that wasn't wasted on junk running gear. These aren't your father's
electric brakes...

-Paul (guy who's towed a lot of trailers a lot of miles and also knows
of accidents directly caused by Cobra brakes)

ps. I have a 10 point list I've thrown out a few times around here in
the past, of why electrics are clearly a better option for glider
trailers in case anyone still clings to the notion that their surgies
are better simply because that's what they have. I mean, the most
expensive glider trailer would obviously come with the best system,
right?

On Jun 13, 7:33*am, sisu1a wrote:
I'm campaigning for converting the Cobra trailers to electric brakes.

+1 * -and let me help you get it started...

Dear Mr Spindelberger, surge brakes suck. I'd rather have no brakes
than deal with the large range of well known and predictable nonsense
that accompanies that outdated overpriced unreliable system. Cobra
should at least offer electrics as a stock option, or at least without
any brakes so we can convert them ourselves with the extra 2 grand
that wasn't wasted on junk running gear. * These aren't your father's
electric brakes...

-Paul (guy who's towed a lot of trailers a lot of miles and also knows
of accidents directly caused by Cobra brakes)

ps. I have a 10 point list I've thrown out a few times around here in
the past, of why electrics are clearly a better option for glider
trailers in case anyone still clings to the notion that their surgies
are better simply because that's what they have. I mean, the most
expensive glider trailer would obviously come with the best system,
right?

I totally agree! Ever tried to back up a hill with your mechanical
surge brakes?? Good luck with that!
My tow vehicle weighs roughly 5 times my trailer with the glider in
it. I don't really think brakes are all that helpful.

On Wednesday, June 13, 2012 9:52:11 AM UTC-4, Bill D wrote:
FYI...

The Cobra trailer for one of the two CAP ASK-21's had developed a
problem with the left tire and had a tendency to sway. The tire was
deteriorating rapidly, wearing on one side with severe cupping. The
tires were relatively new trailer rated bias ply. Theories ranged
from a bent axle to a bad tire with misaligned belting.

A trip to a professional trailer shop uncovered the real cause -
jammed left brake. The Cobra's surge brakes are purely mechanical
with a push-pull rod from the hitch to near the axle where two cables
run to the drum brakes. The left cable had become jammed with dirt
and wasn't releasing the brake causing it to drag until it could
barely roll. The asymmetrical braking was contributing to the
swaying.

There are no dust boots on the cable housing to keep dirt out so this
is likely to be a recurring problem.

All the towing vehicles have electric brake controllers installed so
I'm campaigning for converting the Cobra trailers to electric brakes.

So- Failure to do some routine preventative maintenance constitutes a poor product result.
I've had excellent results with Cobra trailers with surge brakes over the last 15 years or so. Have 4 of them now and satisfied with them.
Just looked at the one in my driveway and it has boots where the cable enters the guides and is well closed off at the brake housing end.
Different experience being reported
It certainly would make sense for people to pick up on Bill's finding and take a look.
UH

On Jun 13, 8:56*am, Grider Pirate wrote:
On Jun 13, 7:33*am, sisu1a wrote:









I'm campaigning for converting the Cobra trailers to electric brakes.

+1 * -and let me help you get it started...

Dear Mr Spindelberger, surge brakes suck. I'd rather have no brakes
than deal with the large range of well known and predictable nonsense
that accompanies that outdated overpriced unreliable system. Cobra
should at least offer electrics as a stock option, or at least without
any brakes so we can convert them ourselves with the extra 2 grand
that wasn't wasted on junk running gear. * These aren't your father's
electric brakes...

-Paul (guy who's towed a lot of trailers a lot of miles and also knows
of accidents directly caused by Cobra brakes)

ps. I have a 10 point list I've thrown out a few times around here in
the past, of why electrics are clearly a better option for glider
trailers in case anyone still clings to the notion that their surgies
are better simply because that's what they have. I mean, the most
expensive glider trailer would obviously come with the best system,
right?

I totally agree! *Ever tried to back up a hill with your mechanical
surge brakes?? Good luck with that!
My tow vehicle weighs roughly 5 times my trailer with the glider in
it. I don't really think brakes are all that helpful.

Are there any electric brake conversion options?

I have a similar problem recently on my Cobra.
The extreme outer edge of contact area of the left tire is wearing and cupping.
The right tire is fine.
The trailer is from around 1997. Aluminum top.
I estimate I am doing about 1000 miles / year.
Behind my Blazer, this trailer runs rock solid, even significantly past 65mph.
No swaying.
I contacted Spindelberger, who replied immediately and suggested to check the bearing, wheel balance and alignment.
The bearings seem fine. No roughness in the bearing and no knacking sounds.
Also the break does not engage.
I have had no problems backing up.
I still need check the balance, the tire alignment, shocks and boots.

Any ideas how/where to check the alignment ?
And how do I test the shocks ? The suspension seems very stiff.

Paul, I would not endorse your "Letter to Spindelberger"

3U.

Am 13.06.2012 16:33, sisu1a wrote:
I'm campaigning for converting the Cobra trailers to electric brakes.

+1 -and let me help you get it started...

Dear Mr Spindelberger, surge brakes suck. I'd rather have no brakes
than deal with the large range of well known and predictable nonsense
that accompanies that outdated overpriced unreliable system. Cobra
should at least offer electrics as a stock option, or at least without
any brakes so we can convert them ourselves with the extra 2 grand
that wasn't wasted on junk running gear. These aren't your father's
electric brakes...

-Paul (guy who's towed a lot of trailers a lot of miles and also knows
of accidents directly caused by Cobra brakes)

ps. I have a 10 point list I've thrown out a few times around here in
the past, of why electrics are clearly a better option for glider
trailers in case anyone still clings to the notion that their surgies
are better simply because that's what they have. I mean, the most
expensive glider trailer would obviously come with the best system,
right?

You have to take into account, that these trailers are fabricated for
the german/european market, and that the only brake system that you will
get approved in Germany are surge brakes. There are no things as
electrical brakes in Europe. We do have air pressure brake systems on
truck trailers, but on these light trailers we only have the brake
system that Spindelberger is using. And yes, they work very well if
properly maintained.

--
Peter Scholz
ASW24 JE

I've had excellent results with Cobra trailers with surge brakes over the last 15 years or so. Have 4 of them now and satisfied with them

The absence of evidence is not the evidence of absence. A lot of
people on this forum *have had problems, and continue to do so.
Electric brakes don't require anywhere near the amount of regiment to
keep from posing an unsuspected hazard on the road, and unlike surge
getups they're easily verified for full proper function *before
ramming someone, or burning off a wheel going down a hill, etc... I
was resistant to the idea too, but Dave Nadler ranting about them some
years back convinced me to look closer at them, and upon closer
inspection found a lot of merits in this system. I converted my
trailer and really grew to like the control and flexibility. In the
meantime, accounts of scary and almost-scary incidents with surgies
continue to pile up on this forum. Electric brakes are not a gimmick,
and in practice you have infinitely more control over them, besides
their other qualities that make them better suited to the realities of
glider trailer duty. I'm not suggesting everyone should immediately
rip their running gear off new trailers and go electric, but if you
ever need to replace the gear (comes up often enough...) it makes zero
sense to waste the extra money for a finicky, higher maintenance getup
with limited function a lot more gotchas and a shorter shelf life.

Would you say that horse owners care more about their horses than
pilots care about their gliders? Why don't they use surge brakes?
(well, other than one European manufacture that doesn't seem to get
it...)

Other than being 100% compatible with any suitable tow vehicle, are
there any advantages to surge brakes that I'm overlooking? The list of
disadvantages is kinda long, and the above advantage is of limited
value since our own vehicles are usually hooked to our trailers...

Are there any electric brake conversion options?

Yes!

The easiest/cheapest I know of is a Dexter Torflex axle (now available
in galvanized flavor!). Most Cobras would use a #9 or #10, or possibly
a custom one in between. It has the same swingarm type independent
suspension and they all have custom welded mounting flanges made to
your specs. http://www.dexteraxle.com/torflex_axles

Here's the basics that need to be figured out to order a replacement:
http://www.humphrey****chandtrailerp...tion-guide.htm
.... and a diagram kinda showing what they're talking about.
http://www.humphrey****chandtrailerp...tart-angle.htm

Once a few of these are done to a range of Cobras, the std formulas
for different years/gross weights will be well known and it will
become a cookie cutter operation. The axles are ~$200, and one needs
the brake equipped hub/drums to go with it, which are around $60-$80
apiece. Another $20-$50 on wiring, $50ish for a breakaway kit, and a
nice controller like a Tekonsha Prodigy or StopRight Intellistop (same
part, different manufacturer) is around $120. Rims/tires are planed
around the offset and hole pattern, and cost whatever you get them for
but these might as well be nice 14 or 15" wheels instead of those
12/13" toys they don't sell anywhere anyways. Wouldn't hurt to put
real (metal) fenders on there too... much more blowout and deer
resilient.

-Paul (who also doesn't endorse my "Letter to Spindelberger"

ps, a quick google search of 'surge vs electric brakes' shows that I'm
far from alone in my dim view of surge brakes...

On Jun 13, 4:45*pm, sisu1a wrote:
I've had excellent results with Cobra trailers with surge brakes over the last 15 years or so. Have 4 of them now and satisfied with them

The absence of evidence is not the evidence of absence. A lot of
people on this forum *have had problems, and continue to do so.
Electric brakes don't require anywhere near the amount of regiment to
keep from posing an unsuspected hazard on the road, and unlike surge
getups they're easily verified for full proper function *before
ramming someone, or burning off a wheel going down a hill, etc... * I
was resistant to the idea too, but Dave Nadler ranting about them some
years back convinced me to look closer at them, and upon closer
inspection found a lot of merits in this system. I converted my
trailer and really grew to like the control and flexibility. In the
meantime, accounts of scary and almost-scary incidents with surgies
continue to pile up on this forum. Electric brakes are not a gimmick,
and in practice you have infinitely more control over them, besides
their other qualities that make them better suited to the realities of
glider trailer duty. I'm not suggesting everyone should immediately
rip their running gear off new trailers and go electric, but if you
ever need to replace the gear (comes up often enough...) it makes zero
sense to waste the extra money for a finicky, higher maintenance getup
with limited function a lot more gotchas and a shorter shelf life.

Would you say that horse owners care more about their horses than
pilots care about their gliders? Why don't they use surge brakes?
(well, other than one European manufacture that doesn't seem to get
it...)

Other than being 100% compatible with any suitable tow vehicle, are
there any advantages to surge brakes that I'm overlooking? The list of
disadvantages is kinda long, and the above advantage is of limited
value since our own vehicles are usually hooked to our trailers...

Are there any electric brake conversion options?

Yes!

The easiest/cheapest I know of is a Dexter Torflex axle (now available
in galvanized flavor!). Most Cobras would use a #9 or #10, or possibly
a custom one in between. It has the same swingarm type independent
suspension and they all have custom welded mounting flanges made to
your specs.http://www.dexteraxle.com/torflex_axles

Here's the basics that need to be figured out to order a replacement:http://www.humphrey****chandtrailerp...tion-guide.htm
... and a diagram kinda showing what they're talking about.http://www.humphrey****chandtrailerp...tart-angle.htm

Once a few of these are done to a range of Cobras, the std formulas
for different years/gross weights will be well known and it will
become a cookie cutter operation. The axles are ~$200, and one needs
the brake equipped hub/drums to go with it, which are around $60-$80
apiece. Another $20-$50 on wiring, $50ish for a breakaway kit, and a
nice controller like a Tekonsha Prodigy or StopRight Intellistop (same
part, different manufacturer) is around $120. Rims/tires are planed
around the offset and hole pattern, and cost whatever you get them for
but these might as well be nice 14 or 15" wheels instead of those
12/13" toys they don't sell anywhere anyways. Wouldn't hurt to put
real (metal) fenders on there too... much more blowout and deer
resilient.

-Paul (who also doesn't endorse my "Letter to Spindelberger" *

ps, a quick google search of 'surge vs electric brakes' shows that I'm
far from alone in my dim view of surge brakes...

I just got back from the 2nd trip to the trailer service shop. They
declared, "It can't be fixed". and recommended electric brakes (which
they don't sell). I took the trailer with partially working brakes
back to the airport where it will stay until we figure out a
solution. I noticed the brakes dragging after a stop. If I
accelerated hard enough to feel the "clunk" as the surge hitch
extended, the dragging went away. Obviously some 'stiction' there
somewhere.

I tend to think if the mechanical surge brakes ever worked, they can
be made to work again at least as well as when new. Then, maybe
diligent maintenance can keep them 'sort of' working. That prospect
doesn't leave me too happy.

One of the weird things is the brake drums carry the wheel bearings
which are two sealed tapered roller type. It would seem this would
lead to some seriously hot bearings under hard braking - I've seen
drums glowing cherry red. It appeared to me there was heat damage to
the bearings.

There's no doubt electric brakes are the absolute best solution. I'm
certain a new axle with electric brakes can be made up to fit the
original mounting holes for a few hundred dollars and this new setup
would be far more reliable and require far less maintenance. Selling
the idea to the people who write the checks, however, will be tough.

I put a Dexter axle with electric brakes on my Cobra works great. I also **** caned those cheap plastic fenders now I can sit on the fender and change my shoes and socks with out falling over.