TSM Disc Brake kit & part numbers

P

patrick flowers

New member
Sep 19, 1997
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>
> The brackets have a 5-1/2" bolt spacing which fits the small GM caliper. I
> don't know if they make a larger bracket and I don't see it in their catalog.
> Note to Patrick: I haven't measured it yet but I think the 80 mm caliper
> has a larger (7" ?) bolt spacing so it might not fit on the brackets you have
> from TSM.

Emery,

You're right of course! The 80mm calipers have 7inch spacing. Now it's
all becoming clear! TSM uses the 3rd generation eldo(79-85) rear
calipers while Bobby Moore and Frank Folkman used the 2nd generation
eldo(76-78) rear calipers. The only way to use the bigger calipers is
to find the 2nd gen eldo backing plates.

More fun!
Patrick
- --
Patrick Flowers
Mailto:patrick

The GMC Motorhome Page
http://www.gmcmotorhome.com
 
>
> Is anyone actually running the 80 mm piston cals to check Alcoa inside rim
> clearances?

It's a very common upgrade. There's not much room left, but it all
fits. Putting the 80mm calipers on the middle wheels is the novel
approach. I've got a cousin by marriage(no southern jokes!) that's
in the salvage business. Guess I need to call and see if he can come up
with some 76-78 eldo rear caliper backing plates.

Patrick
- --
Patrick Flowers
Mailto:patrick

The GMC Motorhome Page
http://www.gmcmotorhome.com
 
On Thu, 22 Apr 1999 18:50:54 -0700 Richard Bachert

>Is anyone actually running the 80 mm piston cals to check Alcoa inside
>rim
>clearances?
I am running oversized truck calipers on the front (don't know the size)
but I haven't experienced any problems with the Alcoas in 5 1/2 years.

David Lee Greenberg
GMC Motorhome Registry
and Boston Homes, Inc.
800-827-9989
 
Is anyone actually running the 80 mm piston cals to check Alcoa inside rim
clearances? Just a horrible thought. I've spent 30 years anticipating how
the overhead handling systems I've designed might fall to earth and "worst
case" is my middle name.
Dick 75 PB in Atlanta

>>
>> The brackets have a 5-1/2" bolt spacing which fits the small GM caliper. I
>> don't know if they make a larger bracket and I don't see it in their catalog.
>> Note to Patrick: I haven't measured it yet but I think the 80 mm caliper
>> has a larger (7" ?) bolt spacing so it might not fit on the brackets you have
>> from TSM.
>
>Emery,
>
>You're right of course! The 80mm calipers have 7inch spacing. Now it's
>all becoming clear! TSM uses the 3rd generation eldo(79-85) rear
>calipers while Bobby Moore and Frank Folkman used the 2nd generation
>eldo(76-78) rear calipers. The only way to use the bigger calipers is
>to find the 2nd gen eldo backing plates.
>
>More fun!
>Patrick
>--
>Patrick Flowers
>Mailto:patrick
>
>The GMC Motorhome Page
>http://www.gmcmotorhome.com
>
 
Patrick, I visited Herr Wittenbecher's site and took another look at the TSM
backing plates and, while I COULD be wrong (that happened once back in '75
), it LOOKS like one could move the bolt holes for the cal out the 3/4"
per side (from the 5" for the small piston cal to the 7" for the 80mm cal)
and, with perhaps a little grinding on the opening for the cals, make the
suckers work for the 80mm. One would have to be careful that so much
material didn't have to be removed as to weaken the backing plate to a
problematic point.
In the alternative, one COULD take the TSM plates to a local machine shop
and have them duplicate the bogie pin end exactly and, while keeping the
dimensions of the cal mounting hole tabs, open the gap as needed to
accomodate the 80 mm cal and move the holes out to the 7" dim.
I wonder what TSM would charge to make the plates for the 80mm units?
Dick 75 PB on Atlanta

>>
>> Is anyone actually running the 80 mm piston cals to check Alcoa inside rim
>> clearances?
>
>It's a very common upgrade. There's not much room left, but it all
>fits. Putting the 80mm calipers on the middle wheels is the novel
>approach. I've got a cousin by marriage(no southern jokes!) that's
>in the salvage business. Guess I need to call and see if he can come up
>with some 76-78 eldo rear caliper backing plates.
>
>Patrick
>--
>Patrick Flowers
>Mailto:patrick
>
>The GMC Motorhome Page
>http://www.gmcmotorhome.com
>
 
>
> it LOOKS like one could move the bolt holes for the cal out the 3/4"
> per side (from the 5" for the small piston cal to the 7" for the 80mm cal)
> and, with perhaps a little grinding on the opening for the cals, make the
> suckers work for the 80mm. One would have to be careful that so much
> material didn't have to be removed as to weaken the backing plate to a
> problematic point.

I looked at mine last night thinking the same thing, but I doubt there's
enough "meat" there for the alteration.

> In the alternative, one COULD take the TSM plates to a local machine shop
> and have them duplicate the bogie pin end exactly and, while keeping the
> dimensions of the cal mounting hole tabs, open the gap as needed to
> accomodate the 80 mm cal and move the holes out to the 7" dim.

Yep, but to avoid further coach "down-time"(gotta get this thing to a
muffler shop), I'm gonna' try to find some gen 2 eldo backing plates. I
might see what it will cost to get them produced if TSM won't.

> I wonder what TSM would charge to make the plates for the 80mm units?

Can't imagine much difference in material cost, so I would think they
would be the same price as the current ones($120 a set). I don't think
they realize how big the demand is tho', cause Skip expressed absolutely
no interest in producing them when I asked. At the same time, he also
said they had been a little surprised at how many of the GMC conversions
they had already sold. Maybe if enough GMCnetters start calling then
they'll get the idea. The phone number is 303-688-6882.

Patrick
- --
Patrick Flowers
Mailto:patrick

The GMC Motorhome Page
http://www.gmcmotorhome.com
 
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