Author Topic: Lithium battery replacement cb750  (Read 570 times)

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Offline la ca fe

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Lithium battery replacement cb750
« on: June 19, 2024, 01:24:00 PM »
I have a non stock cb750 built out of spare parts. Frame ‘76, motor 71.
I want to put a small lithium battery under a seat cowl and would like to know what size you would recommend ?
Will the new battery be compatible with the stock rectifier and regulator?
1973 cb750
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1975 cb750 f

Offline ZingZing

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Re: Lithium battery replacement cb750
« Reply #1 on: June 20, 2024, 11:16:08 AM »
I have a non stock cb750 built out of spare parts. Frame ‘76, motor 71.
I want to put a small lithium battery under a seat cowl and would like to know what size you would recommend ?
Will the new battery be compatible with the stock rectifier and regulator?

I'm not too sure on a right size for a battery, it would depend on how big the area you have to work with is and how big of a battery you really need to make sure you don't get stranded.

I'm pretty sure (edit: I was wrong  :'() though, that a lithium battery cannot be used with the stock rectifier regulator. Something about lithium needing a constant voltage draw and the cb's stock jump around. Get a new rectifier regulator that specifically states that it will work with a lithium ion battery. There's a couple of cheap ones on 4into1.com and more expensive ones if you search around. Don't really know the difference between the two.
« Last Edit: June 20, 2024, 01:05:03 PM by ZingZing »
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Offline calj737

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Re: Lithium battery replacement cb750
« Reply #2 on: June 20, 2024, 11:43:59 AM »
I'm 100% positive though, that a lithium battery cannot be used with the stock rectifier regulator.
This is untrue. It is recommended, and a better choice to get a Lithium compatible Reg/Rec, but it is NOT required.

Shorai is a popular Lithium brand, some have seen issues with AntiGravity (not everyone), but there's many different brands. What you should calculate is the capacity you will require with your setup and charging system.
'74 550 Build http://forums.sohc4.net/index.php?topic=126401.0
'73 500 Build http://forums.sohc4.net/index.php?topic=132935.0

"Of all tyrannies, a tyranny sincerely exercised for the good of it's victim may be the most oppressive. It may be better to live under robber barons than under omnipotent moral busybodies. The robber baron's cruelty may sometimes sleep, his cupidity may at some point be satiated, but those who torment us for our own good will torment us without end for they do so with the approval of their own conscience." - C.S. Lewis

Offline ZingZing

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Re: Lithium battery replacement cb750
« Reply #3 on: June 20, 2024, 01:03:25 PM »
This is untrue. It is recommended, and a better choice to get a Lithium compatible Reg/Rec, but it is NOT required.

Sorry for the misinformation. I thought that if you used lithium with older electrical systems there’s a chance that they can catch fire and melt down. I remember reading in the forums so a new rec reg is on my list but if I don’t really need it I might save some money.
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Offline Shtonecb500

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Re: Lithium battery replacement cb750
« Reply #4 on: June 20, 2024, 10:10:41 PM »
I'm 100% positive though, that a lithium battery cannot be used with the stock rectifier regulator.
This is untrue. It is recommended, and a better choice to get a Lithium compatible Reg/Rec, but it is NOT required.

Shorai is a popular Lithium brand, some have seen issues with AntiGravity (not everyone), but there's many different brands. What you should calculate is the capacity you will require with your setup and charging system.

I have a Shorai, whichever model is for the cb500/550. Its been getting swapped between many bikes consistently, gets charged and sits in a bike or on the shelf over the winter, i've ran the battery dead a few times, I use a battery tender charger on it and I think I got it in 2020, it weighs nothing, its the most reliable thing about my bike honestly. Cant wait to put one in every bike.
73/74'' CB500/550 resto-mod - sold
75' 750f 91' cbr f2 swap cafe - mock up
74' 750 chopper hardtail - complete - sold
74' CB750/836kit - Black mix & match - daily rider - always tweaking
71' cb500 K0 survivor - complete
71' K1 - CANDY GOLD/BROWN Winton kit - in process