T
hank you for buying a Primo Belt Drive! The new Brute Classic or Brute II Classic
belt drive system is intended for use with pre-Evo Big-Twin motorcycles (1936-to-
1984) using a 4-speed transmission. These 1 ½” belt systems will install inside all
pre-Evolution OEM aluminum or tin primary cover assemblies maintaining the stock
external appearance. The Brute II Classic utilizes a belt idler for tensioning, the Brute
Classic does not. Included in the kit is Rivera Engineering’s diaphragm spring operated ”Pro Clutch” suitable for stock, street performance or competition applications. All
Alto clutch plates as utilized in Primo Belt Drives, and Rivera Pro-Clutch kits come with
a Lifetime (limited) Warranty.
installation instructions for the
Primo Brute Classic &
Primo Brute II Classic
BELT DRIVE KITS
ATTENTION INSTALLER...
Prior to starting the following installation procedure make sure the motorcycle is secured properly, and that the
battery is disconnected to prevent accidental start-up. Also please read and familiarize yourself with the instructions. Use only the correct tools for a safe, long-lasting installation.
88
mmmm ((nnoo iiddlleerr))
1111
mmmm ((wwiitthh iiddlleerr))
Brute Classic
8mm Belt
Brute II Classic
11mm Belt
™
BruteClassic 8 27 04.qxd
Remove all OEM drive train components and thoroughly clean the
inner primary. Inspect the inner primary for cracks or other damage.
The serrated plate must remain in place if you are installing the 11
mm Brute II Classic (as shown). It may be removed if you are
installing the 8mm Brute Classic.
Install the KEY in the KEYWAY ensuring that it is correctly seated
and oriented so that the clutch hub will slide into place on the transmission main shaft. If you cannot seat the key correctly, check for
burrs on the key or keyway, deburr as needed and reinstall.
Install the clutch hub / rear basket assembly on the main shaft, and
the front pulley on the motor shaft. Hand tighten the nut on the main
shaft. Hold a straight edge firmly against the inner surface of the ring
gear as shown. The outer edge of the front pulley must line up with
the inner surface of the ring gear as shown before proceeding.
Spacers can be inserted or removed behind the front pulley to
achieve correct pulley alignment.
After correct pulley alignment is established, install the belt on the
pulleys, slide the pulleys into place taking care that the KEY is correctly seated in the KEY WAY (rear pulley-hub assembly). Place a
dab of Rivera’s thread lock (blue) on the threads of the clutch hub nut
prior to permanently installing the nut. Tighten the clutch hub nut
using a high-quality torque wrench & the factory torque specifications
for your particular motorcycle. Repeat the procedure for the motor
shaft nut.
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12532 Lambert Road, Whittier, CA 90606 (562) 907-2600 FAX (562) 907 2606)