Author Topic: 76 CB750F Battery Replace + Electronics Move  (Read 903 times)

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Offline toadm

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76 CB750F Battery Replace + Electronics Move
« on: November 24, 2023, 10:13:26 AM »
Hello. Purchased a 76 CB750F that I am converting to a cafe racer.  Sharing pic of original and work in progress. While I have been riding bikes all my life, this is my first customization. Bear with me :). Looking for some recos on battery and electrical.

Currently, plan is to remove all the turn signals, reduce instrument cluster down to just the speedometer, install LCD headlamp and LCD tail light. I want to significantly reduce the footprint and size of battery. My original plan has following: Installing tuffside cafe racer seat with cone in rear. I was replacing existing battery and electrical holder with a shallow electrical tray (seen in older photos), + welded sheet metal that will sit under rear cone for added space for electrical which you can hopefully see in other photos of completed frame. I was going to keep original battery and install it in new aluminum battery tray under seat electrical tray. But I don't like how it looks. What is the smallest battery (plus any reco'd brands) I can run while still using electrical start? Know there are some mixed opinions on lipo and such. What else do i need to consider/purchase as part of this upgrade?

Additionally, if you've move the electrical from original battery area to under seat/cone like I am attempting, any recos or references on how to approach/organize? I want to keep electrical clean/neat/safe. First time doing something like this. I have a decent understanding of simple wiring, electrical system, how to read wiring diagram...

Any and all recos greatly appreciated.

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #1 on: November 24, 2023, 12:17:20 PM »
What will you do with the original stash box under the seat? That space may be an opportunity for a smaller lithium battery.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Old Scrambler

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #2 on: November 24, 2023, 12:33:51 PM »
Rear tire to hoop-pan appears less than potential shock-bottom ???
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Offline toadm

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #3 on: November 24, 2023, 01:05:12 PM »

Quote
What will you do with the original stash box under the seat? That space may be an opportunity for a smaller lithium battery.
New seat doesnt use that pan / space. Was going to use space in new shallow pan or can get deeper pan and/or under cone of back. This is seat I am using. https://tuffside.com/products/cafe-racer-seats-universal-honda-suzuki-yamaha-kawasaki-bmw-etc.

Quote
Rear tire to hoop-pan appears less than potential shock-bottom
Yeah you noticed one of my many rookie mistakes that needs fixing. I need to steal back approx 1/2" lift to fully clear. I was hoping that one day I would walk back into garage and it would miracle itself fixed. Hasn't happened yet :b

Offline calj737

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #4 on: November 24, 2023, 07:03:55 PM »
Quote
Rear tire to hoop-pan appears less than potential shock-bottom
Yeah you noticed one of my many rookie mistakes that needs fixing. I need to steal back approx 1/2" lift to fully clear. I was hoping that one day I would walk back into garage and it would miracle itself fixed. Hasn't happened yet :b
And you may need more than that under full suspension compression. You might also consider slightly longer shocks once you’ve sorted out the clearance.

I’ve seen folks run the Antigravity 4 amp/hr battery successfully. I’ve also seen a lot of people run the Shorai 14A which is pretty small. I’m not sure the Shorai will fit in that shallow tray. Possible locations are on top of the swingarm along the pivot ,or even nestled along there in a small ally box.
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Offline dragracer

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #5 on: November 25, 2023, 08:58:19 PM »
Its coming along well.  As to the battery,  like others mentioned you should look into using either  a Ballistic,  Antigravity or Full Spectrum litium battery because they take up little space and will also shave weight. If you just need a basic wiring harness, there was a fellow on one of the CB750 Facebook pages selling a kit for choppers with minimal wires and a small switch box. Seems to be perfect for what you're trying to achieve. By the way, whats the status of the stock exhaust you removed?? I'm interested if it's in decent condition for an everyday rider. Let me know please.

Offline toadm

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #6 on: November 26, 2023, 08:52:18 AM »
Quote
I’ve seen folks run the Antigravity 4 amp/hr battery successfully. I’ve also seen a lot of people run the Shorai 14A which is pretty small. I’m not sure the Shorai will fit in that shallow tray. Possible locations are on top of the swingarm along the pivot ,or even nestled along there in a small ally box.

Quote
like others mentioned you should look into using either  a Ballistic,  Antigravity or Full Spectrum litium battery because they take up little space and will also shave weight.

Thanks for this info. Is there anything additional I would need to add to the electrical system if I went lithium? (e.g. special resistors...) If anyone has pics of install, would love to see.


Quote
whats the status of the stock exhaust you removed?? I'm interested if it's in decent condition for an everyday rider. Let me know please.

Intended to sell everything I did not use on bike - including exhaust. Haven't fully inspected or cleaned yet but at a glance appears to good shape. Only specific things I see when just looking at are few small rust spots on chrome on side of baffle facing bike frame. Also 1 rust hole in chrome baffle - also facing bike frame approx. 1/2" x 1/8". If interested, i would do full cleanup and share photos for further inspection. DM me.

Thanks again all. Much appreciated.

Offline calj737

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #7 on: November 26, 2023, 12:38:09 PM »
If you opt for a Lithium battery, you are best to use a lithium-specific Reg/Rec. The stock units work, but the lithium batteries have a slightly different charging curve and prefer (live longer) with the updated type. They run about $100 from Rick’s Motorsports.
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Offline Don R

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #8 on: November 27, 2023, 09:50:49 AM »
 I'll be interested to see your wiring solution; I'm working on a turbocharged bike that needs a powerful battery, fuel pump and pressure regulator. The battery/wiring space becomes pretty valuable.
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Offline dragracer

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #9 on: November 27, 2023, 08:48:59 PM »
I found the guy who makes the bare bones electronic kit. Its on Facebook.  I think this will help you out.

Offline Stev-o

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #10 on: November 28, 2023, 07:57:10 AM »
Following...
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Offline scottly

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #11 on: November 28, 2023, 06:44:53 PM »
I've been using the Shorai LiFe batteries for 6 years or so, and they have worked well so far. The small case LFX14A2 battery has the same power as the large case LFX14L5, which is enough to easily spin my high compression 836, but is the same size as a lead-acid 3 AH battery.
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Offline scottly

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Re: 76 CB750F Battery Replace + Electronics Move
« Reply #12 on: November 28, 2023, 07:19:24 PM »
I’ve also seen a lot of people run the Shorai 14A which is pretty small.
The "A" refers to the polarity: A batteries have the positive terminal on the left, and L batteries have the positive terminal on the right. The case size is determined by a number: 2 is the small case, and the 5 case is larger to fit into the stock battery box.
Don't fix it if it ain't broke!
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