Instruction manual

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it sticks, fix it before you ride. The cruise does not have to be on for the
throttle to stick.
Should the throttle ever stick, pull in the clutch first then hit the kill switch.
Don’t expect the brakes to stop the motorcycle with a stuck throttle; most
motorcycles are just too powerful.
Vacuum Canister:
You’ll need a vacuum canister. You can make one but if it leaks, the cruise
won’t work. We suggest you buy one when you get your cruise control to
use at least temporally for initial testing.
On Murph’s Vacuum canister, the port marked MAN is connected to engine
vacuum. The port marked AUX is connected to the vacuum port on the
cruise servo. Get them backwards and the cruise won’t work.
For automobiles, you can use any vacuum source with the exception of the
vacuum line running to your power brake booster. It’s not safe to tap into
your power brake vacuum booster line.
Motorcycles normally use the ports on the carburetors or throttle bodies
used for synchronization. They have rubber caps on them and you can just
pull them off. Use vacuum from several carburetors / throttle bodies ports
when you can. The more vacuum the better.
Brake Wire Connection:
The purple wire from the cruise control servo must be connected to the
positive side of your brake switch. Normally the rear brake switch has the
easiest access. Connect the purple cruise control wire to the side of the
brake switch that usually has 0 Volts DC but +12 Volts DC when you step
on the brakes.
You can also connect the purple cruise control wire to your taillight brake
wire but you’ll also need a SPDT relay in the circuit. If you have LED
taillights or have even added accessory LED brake lights you need to use a
relay. The purple cruise control wire can’t sense ground through an LED.
Without being connected to Chassis Ground through the purple cruise
control wire, the cruise won’t turn on.
Not all SPDT relays are the same. Some SPDT relays for automotive
lighting applications don’t have the correct internal configuration. You
can buy Murph’s relay which has the correct configuration here:
www.murphskits.com/catalog/product_info.php?cPath=25&products_id=22
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