Omega. The end. The end of that greatest
limitation of the air cooled Boxer, a small capacity charging
system. Now, from Motorrad Elektrik, the Omega alternator kit
for all 1970 through 1995 2-valve BMW twins.
NOTE:1970 through 1973
Slash - 5 must use a / 6 round stator housing, used on all models
from 1974 through 1995 Brush holder is the same part, and can
1977 - 1995 Slash - 7 and
Later , 107mm stator, for all models of R65, R80, and R100 motorcycles
The Omega system is still simply the best money you can spend
for the greatest benefit possible when upgrading or repairing
the charging system of a BMW air cooled twin. The limitations
and inherently poor low speed charging that are designed into
the stock system can make the use of accessories or extended low
speed running a real problem. It's quite a disappointment to discover,
at the end of the day, that the battery will no longer start the
motor It's cold, it's getting dark, and the bike won't crank over
- now what ?
This new Omega system will completely
overcome these shortcomings, and provide plenty of charging current
to power extra lights, heated clothing , or about any other accessories
within reason up to a maximum of 50 amps A battery voltage of
14 volts will remain practically constant from 2000 RPM up This
upgrade can re-define how you use your motorcycle, making it electrically
as capable as a modern motorcycle
This is essentially a complete charging
system, except for the battery. All these new parts fit in the
same places, but are of dramatically improved design, materials,
and construction. The parts are new, but the Bosch design has
been in use on millions of vehicles, and is well known and proven
through time. There are many hundreds of these kits in operation
since 2002, several with over 100,000 miles and at least one with
almost 200,000 miles on it, fitted to a / 6 that is going to do
the infamous Iron Butt Rally - for the second time !
Included in each kit : rotor, stator,
diode board pre-wired with all new wires, diode board solid mounts,
alternator brushes, solid state voltage regulator, charge light
auxiliary circuit, rotor removal tool, and 6mm allen wrench Installation
is bolt-on, except for the need to solder the 3 new stator wires
to the existing terminal block on the re-used stator housing -
and we'll be glad to do that for you, for free, if you want to
send in your cover.
NO MODIFICATIONS WHAT SO EVER need to be made to your motorcycle for installation.
The wiring terminals are all compatible with the original equipment,
so the original parts can be reinstalled at any time with no problem
Eleven pages of clearly written, well illustrated instructions
will make it a snap. Installation should take about 2-3 hours
for an accomplished Airhead wrench, to double that for novice
mechanics. Your times may vary.
The strongest original alternator, found
on the Slash - 6 models, only produced 280 watts / 20 amps The
Slash-5 system only produced 180 watts / 13 amps, and the 1990
and later R100 alternators were downrated to only 238 watts /
ALL of these systems can struggle with low speeds or power losses
from dirty, loose connections Trying to use many accessories results
in having to turn off things as soon as it is not feasible to
maintain 3500 or more RPM The Omega alternator effectively doubles
the charging output, and can do it at significantly lower speeds
while keeping up with loads. When extra loads are applied that
would lower the battery voltage, the system just automatically
cranks up the output to keep up Slogging through dense urban stop-and-go
traffic, or a muddy remote track, the battery will be getting
plenty of charging to keep you running as far as you need to go.
Another refinement the Omega now offers
is a fail-safe parallel circuit provided for the generator warning
light bulb. On the original Bosch system design, the warning light
circuit supplies the exciter current to the alternator rotor.
If the circuit is interrupted by a blown bulb or a failed rotor
winding or worn out brushes, the red light won't come on with
the key and the alternator WILL NOT CHARGE ! Unfortunately, BMW
nor Bosch ever seemed to really emphasize this important information.
Even though bulb failures are actually very rare, it can be a
real show stopper if you aren't aware that a red light that doesn't
come on means a problem, just as surely as a red light that stays
on all the time. Included with the Omega kit is an easy-to-add
330 ohm resistor assembled to a short length of color-coded wiring
and nicely sealed in heat shrink tubing. In the event of an actual
warning light bulb failure, the alternator will continue to function
but you'll need to find out why the bulb doesn't work, in case
it is a more serious issue than just the bulb.
Besides a terrific improvement for your
bike's electrical system, the other valuable part of the kit you
get is the knowledge, experience, exemplary customer support,
and painless 1 year minimum warranty provided by Motorrad Elektrik
Thirty - plus years of BMW motorcycle hands-on technician experience
has provided lots of learning opportunities, and we can usually
help with about any difficulty you might encounter during or after
you install this outstanding product.
/5 Installation requirements...
Please note that installation of this
kit on a 1970-73 model /5 requires the use of a stator housing
used on all 1974 through 1995 models. This is the round aluminum
cover with the brush holder mounted on it, held to the engine
with 3 allen screws.
The stator windings supplied with the
Omega kit are larger in diameter than the original /5 part, and
will not fit The /6 - later stator housing should be readily available
from any number of used parts vendors, and the original /5 brush
holder assembly can be reused.
Also, if additional accessories such
as lights or heated gear are to be used, it is strongly recommended
that a ventilated front engine cover from a 1974 through 1978
model be used to prevent possible overheating of the new alternator
The original /5 front cover has almost
no ventilation for cooling air to enter the front of the engine.
This part should also be readily available used for a nominal
200 Watt Alternator Kit for '55-'69 Boxers $575
This 200 watt, 12 volt alternator
conversion is a completely self-contained unit, with the regulator
and diode board built in - everything fits neatly under the front
cover. The entire alternator attaches to the engine with two bolts
which screw into existing tapped holes. Only three wires need
to be connected to the original harness, and then replace the
bulbs and battery - it's that simple. Real juice for your R60/2
or R69S! The kit comes complete with rotor puller tool, allen
wrenches, fasteners and wire terminals, bulbs, and battery. Think!
Real power for heated grips, electric vest, GPS...
High Output Alternator Conversion for /5 Boxers
Higher Output Alternator for
/5-The 70 through 73 models have a 180 watt charging system and
a small 18 amp-hour battery that has a hard time staying charged.
To get the same 280 watt output that later boxers have, the stator
is rewound and used with a new Omega diode board. Your stator
is returned ready to install, with a new diode board. The supplied
Omega diode board, is the same one as supplied with the
400 watt Omega alternator for Airheads.
Omega Diode Board $90
Heavy duty high voltage automotive
diodes in a large heat sink on a high temperature printed circuit
board - what this means for you is consistent charging, long life,
and a minimum of fuss.
Kit includes new wires and
fasteners. Easy replacement for factory part.
Board Solid Mounts: R90S, All 1000cc Airheads $20.00 / Set of
These all-metal replacements
for the original type of rubber diode board mount will absolutely
insure that the rubber mounts can never de-bond from the fasteners
and allow the board to be damaged by contacting the engine case.
This usually ruins the diode board instantly. Proper grounding
of the diode board is assured, with no need for the typically
inadequate external wire grounds. Poor grounding is a chronic
reason diode boards may have reduced efficiency and short life
NOTE : The following models
DO NOT USE or NEED these solid mounts, as they were designed and
built properly, with the diode board already mounted straight
to the timing case:
1970-1973 Slash- 5 models R50, R60, R75
1974-1976 Slash-6 models R60, R75, R90
1978-1987 R65 and R80 models
New Stator $125.00
New Stators, made in Europe,
for /5, /6 and all /7 and later twins.
Voltage Regulator for Airheads, $38.95
This is a solid-state, non-adjustable
voltage regulator that will help the battery recover more quickly
from the heavy discharge of a startup, or a few minutes of low-speed
running. The regulator DOES NOT INCREASE CHARGING SYSTEM OUTPUT
CAPACITY! No regulator alone can. It does maintain the battery
at a higher 14.2 voltage than the stock regulator allows, which
is closer to the designed best operating voltage of the entire
electrical system and gives more reserve in the battery. There
are no moving parts internally, and it's a simple bolt-on, plug
and play install.
Brushes & Springs
Alternator 70-95 Boxer $7.00 (pair)
Alternator Brush Spring $5.00 (pair)
Generator Brush, 55-69 $8.00 (pair)
Starter Brush, 70-87 $12 (set)
K Bike Starter, Negative $10 (each)
K Bike Starter, Positive $10 (each)