CBR100F Charging System

Experience has taught me to install a voltmeter on motorcycles. During an
extensive trip I noticed low voltage. A Honda dealer mechanic agreed there
was a problem but thought the system would get me home (it did, barely), but
I have a basic question:

How do you determine alternator output?

The regulated output is speced at 12.6 to 15.0 volts at 15,000 rpm. That is
quite a range and correct output would depend on load and battery condition,
etc. Is ther no way to load the alternator and check output? The shop
manual has you check the regulator/rectifier by the resistance of various
contacts, and specifies only two specific branded voltmeters can be used.
The alternator is checked by an ohm meter as well. Is there no way to load
this alternator and then check output voltage? Also, I can find no
specification for alternator output (wattage). Can anybody help?

Thanks.

 

Thanks, Lefty.

 

Hi:

I had lots of problems with dead battery on my CBR1000F. Turns out that
the stock Honda voltage regulator is not up to the task.

I replaced the stock one with an aftermarket one and, at the same time,
replaced the Yuasa battery with a Westco sealed unit.

Goodbye dead batteries.

YOu can read a bit more about the problem at:

foodman123.com/cbr

Tony Dilworth

 

I just bought a twin betty (KZ 750, 1977 2 cylinder) and I was hooking
up 2 extra lights up front (like fog lights only bright blue). When I
hook up the left light and turn on the ignition, everything is fine,
but when I hook up the light on the right side, even by itself with
the opposite light disconnected, it blows the 20 amp fuse. I
connected each light individually to ground, and with separate power
lines going to a wire I found is hot with the ignition on. Any advice
here?

Andy

 

1. Shitcan the blue lights and get some decent white lights.

2. Obviously one of the lights is drawing more current than the other
one. What else is on the circuit with the 20A fuse? If that is the
main fuse, you are simply probably drawing more current than you should
from a bike of that age... if you want to add more lights and/or other
electrical accessories, especially to an old bike, you need to take
special care that you are not overloading the charging system. As I
remember it, my '77 KZ650B1 had a fairly marginal charging system on
the best of days, and it would have been electricide of the stator
to add extra lights to it. All the connectors were oxidised and the
mechanical voltage regulator still worked, but who knows for how much
longer it would have, had I abused it any more than I did.

If you insist on adding additional lights- here is what you must do
first. At a minimum, you need to take apart and carefully inspect
and clean every connector between the stator and the regulator/rectifier,
as well as the connections to the excited field, if it has one like
the KZ650B1 did. Some connectors may have been overheated and lost
their spring temper, which leads to a vicious cycle of more overheating.
So those will have to be replaced. You may even want to do what the
GL1200 folks do, and remove the connectors between the stator and the
rectifier, hard soldering them together to avoid overheating due to
extra current draw.

Any added high-draw accessories should be fused seperately from critical
functions like ignition and the headlight/taillight. If your added wiring
chafes through and shorts to ground, or one of your accessories fails
shorted, you don't want to kill the engine or the main lights. Use a
inline fuse holder and shrink wrap all your crimp connections, NEVER use
the Scotch-Lock style connectors on a bike.

Good luck