Battery life with total loss ignition

[45Brit]

Here's my Sportster 883R flat track bike



Bike has total loss ignition and electric start. Battery is stock Sportster unit, so 18 or 20Ah. I'm sure it will do the distance, it is in racing trim and other bikes use total loss ignition.

My question is, how would it have originally been used? The limitation seems to be the electric starter. There doesn't appear to be provision for a battery tender or jump leads, although the seat is secured by three bolts so easy to remove.

Does anyone have experience of racing a Sportster with this setup and if so, how do they manage battery life?

[sportsterpaul]

When I experienced stator failure on my 2006"R" over in Ontario, a new battery and pulling all fuses except ignition got me nearly 500 miles.

[mac93]

We run a total loss system, it does seem to beat up the battery. only get two or three seasons out of it. We try to put a charger/tender on it as much as possible at the track, seems to help.

[45Brit]

Originally Posted by mac93

We run a total loss system, it does seem to beat up the battery. only get two or three seasons out of it. We try to put a charger/tender on it as much as possible at the track, seems to help.

Oh, it does the battery no good at all! How much use do you get on the day? Particularly, how do you start the bike? Mine has an electric starter and when we took it out for the first time, we found it needed a battery booster to start the bike after the first couple of starts...

[45Brit]

Turns out that after a good long charge, the battery is good for 4 rides and 10-12 starts, plus general warming-up and standing by.

It's still going at that point, but that's a DTRA meeting so "change after 4 rides" seems to be the working answer.

[45Brit]

Rode the bike in a 2-day meeting last weekend, did practice plus three rides, charged the battery overnight and repeat on Sunday.

Put my coat over the bike between rides to keep the wind off the engine - definitely improved starting.

[Vohnsen]

How much do you gain from removing the charging system? i am building a dragbike and thinking about removing stator

[45Brit]

You gain the friction (windage) of the rotating parts, which isn’t really very much.

You lose the weight of the rotor, stator and other components.

You also lose the stresses on the crankshaft and main bearing, of accelerating and decelerating the rotor, which translates to improved throttle response and reliability.

You lose the flywheel effect of the rotor.

You may be able to narrow the engine cases, although drag bikes don’t tend to be concerned with lean angle and clearances

[Vohnsen]

Originally Posted by 45Brit

You gain the friction (windage) of the rotating parts, which isn’t really very much.

You lose the weight of the rotor, stator and other components.

You also lose the stresses on the crankshaft and main bearing, of accelerating and decelerating the rotor, which translates to improved throttle response and reliability.

You lose the flywheel effect of the rotor.

You may be able to narrow the engine cases, although drag bikes don’t tend to be concerned with lean angle and clearances

So very little disadvantage... seems like a good idea since a dragbike dosent charge the battery much since it starts warmsup and races...

[Diogenes415]

I was a road racer (sprints) and would hook up the battery every time I pulled into the pits... no reason to not charge up the battery while the bike was sitting idle. Because of that I have no idea how many sessions the battery would have lasted without a charge and as cheap insurance it would get replaced mid-season... there were plenty of less important uses for the batteries afterward so they never went to waste.