tow bars - Roadmaster Inc.

InvisiBrake
FAQs
Concern
Can I cut the cable to shorten it?
Clarification
No. The cable length is already adjustable in numerous
ways without cutting it:
• The location of the cable anchor bracket (on the
cable) determines how much cable is left over at the
end by the brake pedal. Often you can get all excess
slack removed here. Sometimes you can’t.
• You can wrap the cable around the pulley one time.
This takes up three inches of slack.
• Mounting the cable to the passenger side of the
brake arm, instead of the driver’s side, eats up one
inch of slack.
• The “L-shaped” brake pedal clamp that attaches to
the brake pedal arm is reversible. Facing the bracket
toward the driver consumes two inches of slack.
So there are lots of ways to take up excess slack.
As an aside, the installation manual goes to great
extent to talk about how important it is to plan out
where the pulley, cable anchor bracket and brake
pedal clamp will be located before drilling any holes.
Most of the cable length concerns are solved by properly
positioning the cable assembly. Mounting the
cable in the wrong location will cause issues with having
too much cable left over. But sometimes, on some
cars, there just isn’t any option and that’s when wrapping
the cable around the pulley (only once!), reversing
the brake pedal mounting brackets and mounting
the brake pedal brackets to the other side can take up
to seven inches of play out of the cable.
Concern
If I wrap the cable once around the pulley it looks
like the cable will come off. I’m concerned that wrapping
the excess cable around the pulley only works
until the brake is activated. It looks to me like the cable
would come off the pulley after that. This would cause
the cable to bind and then the system won’t activate
or may even cause the brake pedal to stay depressed,
which might damage the brakes.
Clarification
This was a potential problem that concerned us
as well during the design phase. For this reason we
chose a pulley that had a very narrow gap between
the pulley wheel and the pulley bracket. No matter
how loose the cable gets, it can’t bind because it’s too
large and can’t get caught between the pulley and the
pulley bracket.
Once the brake pedal is released the tension will
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self-center the cable back on the pulley, because
there’s nowhere else it can go.
Concern
There’s not enough room for the brake pedal clamp
and pulley.
In some cars, it looks like there’s not room enough
to mount the brake pedal clamp to ensure enough
clearance for the clamp and pulley. Or, the angle that
I would use to install the clamp and pulley is too severe
for the system to activate properly.
Clarification
On those occasions where there is very little room
between the firewall and the brake pedal arm, you
can:
a. Use a grinder to cut off the excess bracket that
bolts to the brake pedal arm. The bracket is longer
than necessary to allow it to be used on a wide variety
of vehicles. Mount it as far forward as you can
and then trim off the excess bracket. This means the
bracket will protrude about 3/8 of an inch from the
back of the brake pedal.
b. If necessary you can offset the pulley just enough
to make sure the pedal has full and complete movement.
It doesn’t take much movement to gain clearance.
Concern
I just installed an InvisiBrake on a new Honda Fit.
The brake pressure had to be set to 100 psi for the
brake to activate. I’m concerned that the cable anchor
bracket (which is attached with self-tapping screws)
will pull through the floor.
Clarification
One hundred psi is an awful lot. Our averages have
been running around 60 to 70. From our installations
we know that there’s a direct correlation between
how high you attach the brake pedal clamp on the
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