Jump Starting A Bike With A Lifepo4 Battery

[Kermit]

I've fitted one of these fancy lightweight batteries to my Laverda. The Laverda is always a bugger to start and it will soon flatten a battery if for some reason she doesn't fire up after a few attempts. It'll flatten the usual Hawker Odysey battery as well after a few failed attempts.

I've seen an article in Classic Bike where a racer has an Anderson Connector fitted to his lightweight battery on his bike and with which he boosts the bike's battery with the bike's usual battery.

I've been thinking baout doing the same to my bike as to swap the batteries over takes at least an hour. Damn thos Italians and their ideas about weight centralisation. However, I am not sure if this will damage the lightweight battery.

Anyone any ideas as to whether this is safe of best avoided.

I thank you, Kermit.

[blur1]

jumping dead batteries is not a good idea. you'd be better off charging the battery before attempting to crank amps out of it.

you should also not let lithium batteries get too flat.

why is your bike 'always' hard to start?

[Kermit]

jumping dead batteries is not a good idea. you'd be better off charging the battery before attempting to crank amps out of it.

you should also not let lithium batteries get too flat.

why is your bike 'always' hard to start?

My idea was not to wait until the battery was flat, but to use the extra battery to assist the lightweight battery. Then disconnect the booster battery while the bike's on track (It is not a road bike).

The Laverda's (750S version, anyway) have a poor reputation for starting. Laverda use a very small starter motor, which is not really up to the job. I've had the starter ugraded from 2 brushes (set 90 degrees apart) to a 4 brush set up.

I've upgraded the battery cables as they too were very thin and would get almost too hot to touch after a couple of failed attempts to start.

These all help, but the bike always gives the impression that the compression is overwhelming the stater motor. If you catch things just right, it'll start with the merest stab of the button. At other times it'll take 4 or 5 stabs to get it running. It's like an big old British single that you have to ease over the compression stroke before kick starting it.

The Formula versions have a different gear ratio (I think) and they always seem to start much more easily.

I've tried to source the gears from a Formula, but they are rather hard to locate, much like most psrts for Laverdas.

I did buy a paddock starter, but sold that as it seemed to much faffing about on a trackday and I'd expect that it would go walkabout while I was out on track.

[Ducsenna]

I always ran a slave battery, connected it to the RS when starting. it had a YBs14 , now has LiPo, still keep both slave and bike batteries charged up, but connect the external slave when staring, works a treat.

[blur1]

My idea was not to wait until the battery was flat, but to use the extra battery to assist the lightweight battery. Then disconnect the booster battery while the bike's on track (It is not a road bike).

The Laverda's (750S version, anyway) have a poor reputation for starting. Laverda use a very small starter motor, which is not really up to the job. I've had the starter ugraded from 2 brushes (set 90 degrees apart) to a 4 brush set up.

I've upgraded the battery cables as they too were very thin and would get almost too hot to touch after a couple of failed attempts to start.

These all help, but the bike always gives the impression that the compression is overwhelming the stater motor. If you catch things just right, it'll start with the merest stab of the button. At other times it'll take 4 or 5 stabs to get it running. It's like an big old British single that you have to ease over the compression stroke before kick starting it.

The Formula versions have a different gear ratio (I think) and they always seem to start much more easily.

I've tried to source the gears from a Formula, but they are rather hard to locate, much like most psrts for Laverdas.

I did buy a paddock starter, but sold that as it seemed to much faffing about on a trackday and I'd expect that it would go walkabout while I was out on track.

ahh, thanks for the detailed explanation. it makes more sense now.

in your case then, yes, using a slave battery would be fine, and probably a better idea than killing a stand alone battery.

another thing to note is that lithium hates cold weather and being in england your temps are probably cooler than here in oz. (rubbing it in on purpose,lol)

if your bike is only used occasionaly, then pull it from the bike and store it indoors.

[Kermit]

Thanks for the replies. I'll get an Anderson connector and cables made up.

All the bikes batteries and safely tucked away indoors. I'm strictly a fairweather rider, so the Laverda and the Kawasaki are tucked away for the winter.

Roll on next spring.