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Hi I am just wondering how a bigger battery will be fitted in as the battery box on the 2018/9 is so small . are you replacing it with an earlier battery box ?
 

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So quick question, doesn't the amount of electricity flow through a wire depend on the draw, or load?
Not directly. Ohms law states current = voltage / resistance. The resistance is the sum of the wire and the load (and the source, for that matter). So either will limit the current which flows. The resistance of the starter is very low, which is why it can draw so much current. But it won’t be able to if the wire adds resistance.

If we weren't concerned about too much current flowing into the Lithium battery we’d want a nice low resistance in the cable so it wasn’t limiting the current tof the starter. By adding resistance we protect the battery, but can no longer supply as much to the starter so it may or may not turn over, depending on how much the Lithium battery is able to contribute (how dead it is). But if we wait a bit the lithium battery will charge up and be able to help out sufficiently.


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18 gauge wires will be fine to siphon charge into a low battery, but will nearly vaporize under the load of a starter motor. At the very least they'll melt the insulation.

Lets assume the starter is 200 watts. At 12V, this is 16.7 Amps. Or the equivalent of 0.72 Ohms. The jumper cables I described are 0.128 Ohms, so a total of 0.848 ohms. The motor will get 85% of the power (.72/.848), while the remaining 15% is lost in the cable (dissipated as heat). So less than 30W in the cable, spread out over 10 feet. This would make it warm, but not enough to damage it. But in reality we won't have anywhere near this much loss in the cable because the Lithium battery will be supplying current straight to the starter, which doesn't go through the cable.




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Lets assume the starter is 200 watts. At 12V, this is 16.7 Amps. Or the equivalent of 0.72 Ohms. The jumper cables I described are 0.128 Ohms, so a total of 0.848 ohms. The motor will get 85% of the power (.72/.848), while the remaining 15% is lost in the cable (dissipated as heat). So less than 30W in the cable, spread out over 10 feet. This would make it warm, but not enough to damage it. But in reality we won't have anywhere near this much loss in the cable because the Lithium battery will be supplying current straight to the starter, which doesn't go through the cable.




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Not going to bother checking your calculations, I'm sure they're fine, but a starter will pull more than 17 amps. A LOT more. Why else would the battery cables on the machine be so much larger than the wires in the loom?
But hey, it's easy to test. Just remove the battery from the bike, then connect it back with your new jumper cables and hit the starter.
 

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To prevent the issue of accidentally leaving an item on I purchased the Rowe Amplink which cuts items off at a designated time after the ignition is turned off. great device in my opinion. Routing was a bit of a chore but I have sausage fingers that do not fit in the tight confines of any bike.
 

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Discussion Starter #26
After much research, I have not been able to find an AGM that will fit the 2018 battery box. It is an incredibly tight fit. I'll just stay with lithium I guess.
Lot of good info on this thread though. Thanks for responding.
 
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