kickstart only cb77, smallest battery needed?

v30magna

v30magna

Been Around the Block
what's the smallest battery I can get away with and still get a spark on my cb77? I want to use a small SLA like you find in alarm systems and battery backups. 1.2AH? 2.2Ah? I've got a 35w Headlight and a 5w/10w tail, that's it, and they won't be on during startup.
 
Well, Watts / Volts = Amps.

Headlight 35w/12v = approx 3 amps

Tail Stop 10w/12v = approx 1 amp

Coils will draw approx 3-5 amps.

So MAX you are looking at somewhere around 9-10 amps.

Whats the charging system rated for?
 
If you're keeping the starter motor, an SLA battery won't work. Those spade connectors can't handle the level of current needed to turn over the motor. They'll melt.

As for the size of the battery, you need at least 9Ah without working on the charging system. The CB77 doesn't come with a voltage regulator and so it depends on having a large enough battery to absorb the extra amperage that is generated. It does this by boiling off the electrolyte, so an AGM/sealed/gel battery isn't going to work either.

You can probably get down to 6Ah or so if you plan to get rid of the electric start and upgrade your charging system to include a regulator (or a combination regulator/rectifier).
 
Thanks for responses!

I figured the blade connectors wouldn't be able to turn the starter.

I was gonna delete the kicker and use a shaved CL77 case cover, but I opted to delete the battery box so I could show off the schwinn style frame tube.

I have heard about the charging system being cave man tech, so that's why I've asked you guys about it. Would the 9ah SLA be OK to run lights and coils with a modern rec/reg? If I turn it on it's side, it should hide away under a seat pretty well.
 
The honda305 forum has info about using a bridge rectifier, what could I do for a regulator? Could I use something like a chinese dirtbike regulator? Or maybe something else generic, like a Honda Rebel or a TRX300 regulator?
 
Hi,

First off, dont shoot the messenger if something blows up.

cb77%20wiring.jpg


This is the wiring diagram we're talking about right? If so, you can connect the pink and yellow wire from the AC dynamo together, creating 1 new yellow wire.
The pink wire in the diagram goes right to the headlamp. It's a build-in safety. The pink coil will help generate wattage when the head light is on 'HIGH'.
Combining pink and yellow will result in pink and yellow both 'ON'. More wattage :)

Anyway - You then have a brown and a yellow(with pink) wire coming from your dynamo.

This 2 wires give AC current between them. Low revs, low current. High revs, high current.
I suggest reading up on this article asto wich RR you'll need:
(DO READ IT, VERY INFORMATIVE)

http://www.hondatwins.net/forum/viewtopic.php?f=46&t=14530&start=90

In this article, people have tested some different RR's (regulator/rectifier) and posted their findings. The Kohler one used in lawnmowers seemsto be the perfect candidate.
Those go for around 20$ on eBay, brand new.

Good luck!
 
ok, i'm reading the rec/reg stuff. So my charging system is like thiers? (the subject on the link is for 1970s 250, 350, and 360 is why i ask) Also, have you tried splicing the pink and yellow? Does that bother phase?
 
ok, i read the pink wire/yellow wire stuff too. cool. the 9ah generic SLAs present a thinner profile than the 5ah and 6ah batteries i've found, when you lay the 9ah on it's side it is about 2.7 inches. I just gotta make sure there's enough room, these 305s are micro-machines. It'll hang down a little, if I can't deal with it, I'll gang together a few smaller SLAs or pickup a balistic, or couple cell packs ganged together. hopefully the kohler reg (20A rated) will provide smooth enough charge not to pop the SLA. Probably put in a permanent trickle charger pigtail and restrict headlight use to inspection sessions only.
 
v30magna said:
ok, i read the pink wire/yellow wire stuff too. cool. the 9ah generic SLAs present a thinner profile than the 5ah and 6ah batteries i've found, when you lay the 9ah on it's side it is about 2.7 inches. I just gotta make sure there's enough room, these 305s are micro-machines. It'll hang down a little, if I can't deal with it, I'll gang together a few smaller SLAs or pickup a balistic, or couple cell packs ganged together. hopefully the kohler reg (20A rated) will provide smooth enough charge not to pop the SLA. Probably put in a permanent trickle charger pigtail and restrict headlight use to inspection sessions only.
Click to expand...

If you haven't purchased the Kohler yet, I sell purpose built units from my website (listed in my signature). They're a bit more expensive than the Kohler, but the quality is better, too.
 
Also... I think Bert might have his wires crossed (please forgive the pun). The pink wire does not go to the headlight. It gets routed through the switch to the output yellow wire which joins back into the main yellow. The headlight is still DC, not AC.
 
If the schematic is right, the pink wire (2 pair coil alternator) goes to the light switch. Only the yellow goes to the regulator.

So Bert may be right.....

Schematic for this model is different then later models, colors are little skewed.

This bike has no regulator from the factory. However, he could combine the outputs, run through a reg rectifier, and change headlight to DC.

As is, the headlight wouldn't work on the battery at all....engine running only...AC..interesting....
 
The lighting switch gets fed DC current from the combo switch. When switched to the on position, DC current flows from the black wire, through the switch, to the brown wire. The brown wire is what provides power to the headlight dimmer switch.

Back to the lighting switch... when on, the yellow and pink wires are bridged, completing the pink coils' connection to ground. So the lighting switch is doing double duty. It turns the headlight on, but also adds additional charging to the bike.

Headlight is not run on AC.
 
Your right. Crazy colors confused me. Pink and yellow connect on left side lighting switch. Missed that. Some of the cooler bike did have ac lights.


Sent from planet Earth using mysterious electronic devices and Tapatalk
 
I'm color blind, but all my street CB77s had a rectifier and 12v DC lights and no regulator.

Sonrier is spot on there about not using AGM or LiPo unless you regulate the 12v DC charge. If Matt (Sonrier) has a suitable regulator or Reg/rect, I'd get that and ask him for instructions and you should be good to go.
 
Best way to do it is ignore/remove the wiring going to handlebar switch, wire the alternator as a 3 phase unit (use 3 wires as outputs)
Use a combined reg/rectifier from almost any permanent magnet modern bike.
You will have about 1 amp 'spare' so you should use 10x that amount, using a 1.2 A/hr battery will cause it to 'boil'
SLA just means 'Sealed Lead Acid', they have a pressure relief valve which will vent corrosive gas when battery overheats
Personally, I use 7A/hr SLA which is a bit small but will work for a few years
The LiFePo batteries will probably explode or catch fire, charging system isn't good enough to use them unless you fit a monitoring system with automatic shut down (you'll probably have to build your own using RC components)
 
great signature crazypj!

I'll have to look up 3 phase now too...

I'll consider sonrier's rec/reg in my decision. I gotta figure out if i want 3 phase or the Onan/sonrier unit now. gotta put in some reading time and weigh the variables

lowest modification required to my existing ideas on the project
smoothest most optimal output
part price/availability
style
 
Three phase isn't a choice you usually get. Either your alternator is single phase or it's three phase. You can change from one to the other, but it requires modification to the windings on the alternator.
 
v30magna said:
would the 3 phase work correctly? what rec reg did you choose to use?
Click to expand...

A three rectifier would work if you hook it up correctly, but they're usually more expensive than a single phase unit, so if you're buying new, there's little point in using the three phase option.

The reg/rec I use is also the one I sell.
 
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