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CB77 keeps running it's battery dead... while running.

Charging System, Wiring, Lighting
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MBellRacing
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Posts: 178
Joined: Sat May 15, 2010 2:23 pm
Location: San Mateo, Ca

CB77 keeps running it's battery dead... while running.

Post by MBellRacing » Thu Jun 14, 2018 9:32 am

Hey guys,

For the first time in 8 years, I had the bike running out on the highway, now with the OKO CVK carbs and some other goodies. That bike is a riot. Not fast, but SO rewarding to ride! The problem is, my rides are about 15-20 minutes long because the battery doesn't stay charged. Basically, I can idle the thing all day long, in my garage, 12.69-12.80V consistently, never more than a 0.10V change. Revving it brings voltage up to low 13's, so all SEEMS well. However, once I'm out on the road, I'll notice my cheater AEM O2 sensor gauge start to flicker and eventually brown-out. Then the headlight dims, the LED taillight stops working, and eventually, I lose spark and the bike dies.

Now, I recognize that I have lots of interesting little electronic upgrades on this bike, but nothing stands out to me as something that would cause sudden loss of power generation. Here're all the relevant electronic system notes:

-Shorai Lithium Ion Battery (new 2017, used on other bike, tested good)
-Charlie's Place Rectifier/Regulator
-All generator wires running to Charlie's rectifier (at Charlie's recommendation)
-CB92 Generator Stator (someone told me it was higher output... not sure if true)
-Elektronik-Sachse Crankfire Electronic Ignition (w/ control module mounted under the battery)
-Dime City Cycles LED Taillight
-AEM UEGO O2 Sensor Gauge (w/ brand new Bosch LSU 4.9 sensor in both cylinders)
-Stock-style headlight with jumper to run high beam all the time (maybe an issue?)
-Brake switch now routed to front brake



That's about all I think of, wiring wise. Please let me know if anything seems odd, or if anybody has had a similar issue. How much wattage should that generator put out under normal use? Is there a curve somewhere? One of my hunches was that the O2 sensor kit was drawing too much current when the O2 heater was on, but again, it SEEMS to charge fine just idling in my garage. My other thought is an interaction between the electronic ignition and the Dyna coils. However, I believe Elektronic-Sachse actually recommends modern coils like this for their kit!

Very confusing, very frustrating. Any help would be appreciated!

Thanks!
[/list]

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G-Man
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Re: CB77 keeps running it's battery dead... while running.

Post by G-Man » Thu Jun 14, 2018 11:12 am

A couple of things jump out.....

The CB92 ran a 6v system. This does not mean that the stator cannot generate 12v but it might be limited in current capacity.

Why not try running the bike without the headlight to see if you have enough capacity to run that and charge the battery?

And thirdly, you should be seeing around 13.6 to 13.8 on a fully-charged battery.

Fourthly, try measuring the voltage and current when you are riding. The stock CB72 alternator delivers 50w maximum, I think. Easy enough to see if you are 'over budget'.


G
MBellRacing wrote:Hey guys,

For the first time in 8 years, I had the bike running out on the highway, now with the OKO CVK carbs and some other goodies. That bike is a riot. Not fast, but SO rewarding to ride! The problem is, my rides are about 15-20 minutes long because the battery doesn't stay charged. Basically, I can idle the thing all day long, in my garage, 12.69-12.80V consistently, never more than a 0.10V change. Revving it brings voltage up to low 13's, so all SEEMS well. However, once I'm out on the road, I'll notice my cheater AEM O2 sensor gauge start to flicker and eventually brown-out. Then the headlight dims, the LED taillight stops working, and eventually, I lose spark and the bike dies.

Now, I recognize that I have lots of interesting little electronic upgrades on this bike, but nothing stands out to me as something that would cause sudden loss of power generation. Here're all the relevant electronic system notes:

-Shorai Lithium Ion Battery (new 2017, used on other bike, tested good)
-Charlie's Place Rectifier/Regulator
-All generator wires running to Charlie's rectifier (at Charlie's recommendation)
-CB92 Generator Stator (someone told me it was higher output... not sure if true)
-Elektronik-Sachse Crankfire Electronic Ignition (w/ control module mounted under the battery)
-Dime City Cycles LED Taillight
-AEM UEGO O2 Sensor Gauge (w/ brand new Bosch LSU 4.9 sensor in both cylinders)
-Stock-style headlight with jumper to run high beam all the time (maybe an issue?)
-Brake switch now routed to front brake



That's about all I think of, wiring wise. Please let me know if anything seems odd, or if anybody has had a similar issue. How much wattage should that generator put out under normal use? Is there a curve somewhere? One of my hunches was that the O2 sensor kit was drawing too much current when the O2 heater was on, but again, it SEEMS to charge fine just idling in my garage. My other thought is an interaction between the electronic ignition and the Dyna coils. However, I believe Elektronic-Sachse actually recommends modern coils like this for their kit!

Very confusing, very frustrating. Any help would be appreciated!

Thanks!
[/list]
Last edited by G-Man on Thu Jun 14, 2018 3:15 pm, edited 1 time in total.
'60 C77 '60 C72 '62 C72 Dream '63 CL72
'61 CB72 '64 CB77 '65 CB160
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'67 S90 '77 CB400F

MBellRacing
honda305.com Member
Posts: 178
Joined: Sat May 15, 2010 2:23 pm
Location: San Mateo, Ca

Re: CB77 keeps running it's battery dead... while running.

Post by MBellRacing » Thu Jun 14, 2018 11:49 am

THANKS G!

Interesting about the 6V system! I don't recall who told me to run it, but I'm a bit mad at them now!

I will run the bike without the headlight, but here in California, you're required to have it. I'll risk it for a minute or two!

I was planning to run the bike with a multimeter taped to the tank, this weekend, to see when/how/if it is dropping. When I first measure the bike, with it off, it reads 13.5V-ish. When it starts, it drops to 12.8V immediately, then hovers around 12.7V, like I said.

Thanks for the info!
G-Man wrote:A couple of things jump out.....

The CB92 ran a 6v system. This does not mean that the stator cannot generate 12v but it might be limited in current capacity.

Why not try running th ebike without th eheadlight to see if you have enough capacity to run that and charge the battery?

And thirdly, you should be seeing around 13.6 to 13.8 on a fully-charged battery.

Fourthly, try measuring the voltage and current when you are riding. The stock CB72 alternator delivers 50w maximum, I think. Easy enough to see if you are 'over budget'.


G
MBellRacing wrote:Hey guys,

For the first time in 8 years, I had the bike running out on the highway, now with the OKO CVK carbs and some other goodies. That bike is a riot. Not fast, but SO rewarding to ride! The problem is, my rides are about 15-20 minutes long because the battery doesn't stay charged. Basically, I can idle the thing all day long, in my garage, 12.69-12.80V consistently, never more than a 0.10V change. Revving it brings voltage up to low 13's, so all SEEMS well. However, once I'm out on the road, I'll notice my cheater AEM O2 sensor gauge start to flicker and eventually brown-out. Then the headlight dims, the LED taillight stops working, and eventually, I lose spark and the bike dies.

Now, I recognize that I have lots of interesting little electronic upgrades on this bike, but nothing stands out to me as something that would cause sudden loss of power generation. Here're all the relevant electronic system notes:

-Shorai Lithium Ion Battery (new 2017, used on other bike, tested good)
-Charlie's Place Rectifier/Regulator
-All generator wires running to Charlie's rectifier (at Charlie's recommendation)
-CB92 Generator Stator (someone told me it was higher output... not sure if true)
-Elektronik-Sachse Crankfire Electronic Ignition (w/ control module mounted under the battery)
-Dime City Cycles LED Taillight
-AEM UEGO O2 Sensor Gauge (w/ brand new Bosch LSU 4.9 sensor in both cylinders)
-Stock-style headlight with jumper to run high beam all the time (maybe an issue?)
-Brake switch now routed to front brake



That's about all I think of, wiring wise. Please let me know if anything seems odd, or if anybody has had a similar issue. How much wattage should that generator put out under normal use? Is there a curve somewhere? One of my hunches was that the O2 sensor kit was drawing too much current when the O2 heater was on, but again, it SEEMS to charge fine just idling in my garage. My other thought is an interaction between the electronic ignition and the Dyna coils. However, I believe Elektronic-Sachse actually recommends modern coils like this for their kit!

Very confusing, very frustrating. Any help would be appreciated!

Thanks!
[/list]

User avatar
Tim Allman
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Posts: 437
Joined: Tue Dec 02, 2014 9:25 am
Location: Guelph, Ontario, Canada

Re: CB77 keeps running it's battery dead... while running.

Post by Tim Allman » Thu Jun 14, 2018 9:04 pm

MBellRacing wrote:THANKS G!

Interesting about the 6V system! I don't recall who told me to run it, but I'm a bit mad at them now!

I will run the bike without the headlight, but here in California, you're required to have it. I'll risk it for a minute or two!

I was planning to run the bike with a multimeter taped to the tank, this weekend, to see when/how/if it is dropping. When I first measure the bike, with it off, it reads 13.5V-ish. When it starts, it drops to 12.8V immediately, then hovers around 12.7V, like I said.

Thanks for the info!
You might want to check the rules about daytime headlights. Here in Ontario the law was passed in the 1980s requiring motorcycles to have lights on all the time but bikes made before then were grandfathered. It's a great idea to increase visibility but you might not get a ticket if you ride without your headlight on.

rrietman
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Posts: 561
Joined: Mon Oct 13, 2008 6:45 pm
Location: bellingham wa.

Post by rrietman » Fri Jun 15, 2018 12:05 am

you need to get a 12v stator. the CB92 might give you good voltage at no load, but will fall off at speed.PM me if you need a stator. plus--I will take that CB92 off your hands if you don't need it.
Thanks
Randy

MBellRacing
honda305.com Member
Posts: 178
Joined: Sat May 15, 2010 2:23 pm
Location: San Mateo, Ca

Post by MBellRacing » Sat Jun 16, 2018 7:12 pm

Thanks, Randy! Yup, I swapped in my old [and ugly] CB77 stator and it did much better. Instead of dropping about 0.1V/minute, it now does it over about 5 minutes. Still not perfect, and I've found that the headlight is definitely part of the problem. I think I just have too much going on, electrically, so I've devising a solution. Tested one today, it worked pretty well but broke during a ride. I'll fill you all in once it is dialed in a bit better!
rrietman wrote:you need to get a 12v stator. the CB92 might give you good voltage at no load, but will fall off at speed.PM me if you need a stator. plus--I will take that CB92 off your hands if you don't need it.
Thanks
Randy

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