Enduralast rotor upgrade for BMW airheads: First Impressions
The
following includes my first impressions after installing an Enduralast 450 Watt system from
Euro Motoelectrics
The bottom line is that from about 1200-1300 rpm onwards, the system puts
out 14.1 to 14.2 volts. At idle, it’s between 12.4 and 12.6 volts. I
installed a Datel volt meter to give me a constant read-out during riding. I
puttered through town this evening and briefly hopped on the freeway. At all
points the voltage was constant between 14 and 14.2. Yesterday, after
ensuring I had rigged everything up correctly, I wired up an electric vest
and a 70 Watt power inverter to the battery. Flicking the high beam on and
off at idle makes the voltage blip, but it returns a steady number after a
second or so. Since the inverter and jacket didn’t seem to make a difference
in the voltage readout yesterday, I did not wire them up for the test ride.
The kit contains a rotor (solid magnet) and stator, a mounting bracket, a
rectifier and a set of wires, connectors and eyelets etc. I used only a
fraction of this as the kit caters to an array of mounting options. There’s even a rotor puller bolt included.
The installation is relatively straightforward, but you do need to read the
manual carefully. The wiring diagram is a no-brainer. Since I am going to
move this system to my G/S in a few months, I did not bother removing any of
the original wiring. Since none of it is needed in the meantime, I taped up
all the ends and left them where they were.
Installation
First job is to remove the original stator, rotor, diode board and voltage
regulator. I left the voltage regulator in place, courtesy of two spun
screws.
Mounting the rotor is the same procedure as a regular one. Since we’re
dealing with a solid magnet rotor, you want to make sure your wallet and
credit cards are not in the vicinity. I wondered about the Hall sensor with
this thing nearby, but a timing light check confirmed nothing had changed.
The stator is mounted between two aluminum brackets and screwed into place
with 3 screws in the same location as the original. No brushes here … this
is a “contact-less” system. As with the original stator, you need to slowly
easy it into place and tighten the screws in turn. There is one big wire
going up and out of the front cover cavity, that’s it. The only other wire
under the front cover after the install is the wire to the timing can (for
post-81 machines). Lots of space to mount a small box with tools where the
diode board was… hmm.
I ended up mounting the rectifier to a frame tube and ran a car-size ground
wire to the battery negative. This was pure laziness on my part, as others
have installed this rectifier under the tank after removing the voltage
regulator. It fits in that space.
The wiring is simple: The voltage regulator plug ground and blue wire are
used (with spade connectors), a wire (with provided 30 amp fuse) to battery
positive. Two plugs connect the rectifier to the stator, one wire connects
to a switched positive. For the latter you need to connect to a wire that
gets “hot” when the ignition is on. One of the spades on my coils was hot so
I used that.
I spent most of my time trying to figure out where I wanted to mount the
rectifier. The RT has less space than other configurations and I could not
remove the voltage regulator. In hindsight, I preferred it that way.
During riding I noticed not much difference, except that my stock voltage
regulator was reading much higher than before. It’s nice to know that even
when you’re loitering through town you’re not draining the battery. I was
somewhat concerned that given the strength of the magnet, there would be
more drag on the motor and hence I’d have to adjust idle (more fuel
consumption…) but that proved to be unfounded. As well, the rotor weighs
less than the stock one. I touched the rectifier at the end of the ride to
see if it had heated up, but it was cold.
I’m going to eye-ball this setup for a while and decide whether I want to
move this over to the G/S. This whole thing started when I contacted John
Rayski (Euromoto Electrics) and quizzed him on whether he wanted to have a
“guinea pig” for his new system. He was happy to provide me a system,
gratis. Next April, I’m off for a LONG trip across
Europe to China and beyond. In order to eliminate the need for carrying an
extra rotor and diode board, as well have better charging, I want to take
this setup. Since it’s on the RT, I’ll put ample mileage on it between now
and then to provide me with enough comfort to put it on the G/S.
Another (small) benefit of this system is that the charging light, although
powered as with a stock setup, is not required to function for charging to
take place.
Pictures of the rectifier mounting
Comparison of 3 rotors
The middle one is the Enduralast one. The left one is stock and the right one is a Motorrad Electric rotor. The Enduralast is the lightest.
Pictures of another install (used with permission)
Rectifier install on the same GS
Pictures at various speeds on my RT
Note: The digital voltage readout at the left in the pictures below is about
0.2 volts below what I measured at the battery with the same voltage meter.
Probably due to some loss as I spliced the volt meter into a switched
circuit up front. The high beam is on during the test.
800 rpm
1000 rpm
1100 rpm
1500 rpm
Feb 1, 2006
After a few thousand miles, the next step is to move the Enduralast over to
the G/S. I contacted John and got a spare rectifier to take along on the
trip. Mounting the rectifier proved unexpectedly easy. I was dreading having
to fight for space under the Acerbis tank where I'd only last week managed
to squeeze in an alarm system. A visit to my welder netted the simplest of
solutions. After debating a bracket welded to something given the tank's
hogging of all the frame space, he suggested an aluminum plate right behind
the battery. That would allow the battery straps to catch the plate and
provide a mounting surface for the rectifier. Since it's about as close as
you can get to the battery, this seemed an excellent plan. Below is a pic of
the aluminum plate. It's 5.5 X 7 inches. It sits right along the battery
(which is the same size) and fits snugly between the battery box and the
battery. The rectifier points backwards towards the rear fender. It's
completely in the open and does not interfere with anything. I run a full
toolbox under the seat, FWIW. The wiring runs downwards. Come to think of
this, I should have followed the same system on my RT. I run a smaller
diameter Odyssey PC 680 and there is a LOT of room at the front of the
battery to do something similar.
Feb 23, 2006
Trip preparations have kept me from playing any further with the setup above
until yesterday. I received a spare rectifier from John at Euro
Motoelectrics 3 weeks
ago. I wired the system up on the G/S and ensured I had matching connections
on the spare for an easy swap-in if needed. The pics below link to the
unadulterated full-size ones. They are around 2MB each.
As you can see above, the install is complete. You are looking at the left
of the bike (R80G/S). A few things still need to be taken care of, such as
shrink tubing over a few connectors and protective cable sheathing, both of
which I ran out of towards the end of the day. I opted to cut off all the
connectors to the rectifiers and replace them with SAE 10 gauge two-prong
plugs, as seen in the lower left of the picture, although this one is
auxiliary power for an air compressor/electric vest. Maybe overkill, but
this allowed me to configure the spare rectifier the same way, so that in
case I needed it, it would be much simpler to replace.
The backing plate was measured to fit the battery and sits inside the
battery tray at the bottom. At the back, I have 2 counter-sunk screws to
avoid contact with the battery case and for security I added 2 strips of
bicycle inner tube as vibration buffer. Again overkill as the battery case
is rubber mounted. The battery straps hold the battery in place just fine
and there's a tad more tension due to the plate, but not much. The fender is
the closest thing to the rectifier, but there's about 3 mm of room in
between. A perfect spot for the rectifier.
Here's a second view from the left side:
Here's a view from the top. The red wire is an extra ground.
So far, so good. I'll update this page if needed in the future.
Jan 15, 2007
I just returned from a 20,000 mile trip through Europe, Middle East and Asia. The system worked flawlessly. More info at http://www.nohorizons.net
Feb 1, 2008
I installed an Enduralast on my RT as well now.
More infomation about the Enduralast at the Euro Motoelectrics website: http://www.euromotoelectrics.com/enduralast.html