Anyone use a lithium battery on there CB ??

[cb750stu]

Hi Folks im looking into battery options for my CB 750 i want to mount it under my cafe racer seat along with my electrics !!!
I dont have electric start just kick only

Ive not got a lot of space left so i was thinking about the lithium route as they are alot smaller,

Just wondering if any of you guys run with one and what are the pros and cons of using one ??

Regards

Stuart

[Lobo]

Hi Stuart,

I've used a 'Carrot' LIFEPo battery in my CB750K2, ...a drop-in replacement. Early days yet, no problems that I've encountered and so far very impressed (and likely I may go this route with the 400F later). My problem tho' different to yours, my bikes go a long time with no 'visits' from me, and so I needed a battery that can go ages and suffer no discharge.

The weight is just bloody amazing, its about as heavy as a conventional case with no internals.

What doesn't impress is the price...at > £100.

A few differences with the way they charge (eg NO trickle charging) - but all in the info guff.

http://www.carrotcycles.co.uk/index.php?_a=category&cat_id=217

Cheers,
Lobo

[Bryanj]

What with Boeings problems with batteries i am a tad dubious mate!!

[cb750stu]

What problems might they be

Cheers

[Lobo]

Aw...live dangerously why don't ya!

If your groin feels nice'n'warm, accompanied by the burning smell of flesh simply pull over, dismount...  and pour a bag of ice-cubes down your pants. (free ice-tray comes with every purchase).  Though realistically  guys, who on this '70's Hondas' forum is still interested in reproducing anyways!!

Or, go the Boeing route & encase the battety in a 3/4" titanium box... which should leave you enough room for an "AA" or two...

[neat street]

Hi, li-ion can be a tad funny, as not only should it be charged correctly, but the discharge should be as well, I am not sure how this works on a bike, but with cordless tools, you cant fit a li-ion battery to an old tool that was designed for ni-cad, or nmh, as the discharge could cause problems with the life of the battery, and as said before, overheating and catching fire. I would suggest looking into this in more detail first? maybe try and contact a battery manufacturer? the three main ones for these are Panasonic, Sony, and energiser. I know Panasonic are based in Bracknell Berkshire.
hope this helps?

[Lobo]

Agreed, although these batteries are specifically made to be compatible with old bikes (if you believe the blurb) and (I think) in the casing included a bit of wizardry to ensure all's well. I am quite certain its no gash set up as basic as selling us a LIPO to slot into your '70s Honda.

Agreed you have to be careful with external charging... all this highlighted & special chargers for sale.

One other big plus I note is the cranking rpm.... it bloody whizzes over (CB750). Perhaps the old Pb was indeed on its last legs, but impressive none-the-less.

I have messed with LiPos on RC Helicopters and the like; they are capable of a fearsome amount of discharge and require an awful lot of respect. Not had an issue yet, tho there is perhaps an argument against placing one under your gentleman's log cabin, plugged into a 70's charging circuit and within inches of 3 galls of premium!

But... so far impressed / at ease with my Carrot specific CB LIFEPo.

[Waggles]

I think all Li based battery packs contain circuitry and heat sensors to prevent overcharging etc but I don't think I would connect one to a bikes charging circuit, wouldn't trust it ( even tho my gentlemans sausage is only used for test the temperature of welding torches these days )

[Lobo]

Ok gents,

Have written to a battery guru on this subject (a uni guy building electric road vehicles) basically asking "Should I be afraid". A little on the short side, but enough to placate me.... his answer...

Hi Simon,
 
Happy to help
 
It takes rather a lot to set a LiFePO4 battery on fire (you basically have to heat it above ~250 deg C) - its the most stable of all the lithium chemistries (most of the battery is actually Iron copper and aluminium)
 
To stop the battery from overcharging, the voltage can't be allowed to go above 16v, and shouldn't be held at above 14v continuously
 
the tricky thing with mechanical regulators is they rely on the battery to do much of the actual voltage regulation
 
While the LiFePO4 battery won't catch fire, it's service life may be a bit on the short side
 
If that happens, a new regulator would sort it out
 
The other thing you have to watch out for is those Shorai batteries have little actual capacity, so if the alternator ever dies it can't run the lights or the bikes ignition for very long

Regards,
Matt

[cb750stu]

Cheers guys for the info some interesting points made I think I'll give one a go and see how I get on

Cheers