these are becoming popular in the jet ski crowd- http://antigravitybatteries.com/
If it’s a legit battery pack then it should have a charging circuit built in and should be ok. If not I wouldn’t do it, I’ve heard they blow up easily but I don’t have any actual evidence to back that up.
I was thinking a large cap but then you’d never be able to start the bike.
On the car here at school I ran a bosch type fuel pump that pulled 8 amps at start up and 2-3 steady state. (turbo wr450):
Even their smallest one is 4x too big. It doesn’t need to turn a starter over.
Travis, no charging circuit. That’s what worried me. I do have a large cap I’m installing also.
Per google it’s pretty simple to add a charging circuit. I bet you can either make one quick out of perf board or buy one pre made.
Be careful with lithium IRON batteries (shorai, etc), if they get below some nominal voltage (10-11ish) they go through a chemical reaction and aren’t batteries anymore.
I’m sure it’s doable, I just don’t really have the time to devote to working out the logistics of it right now.
Put a solar cell on it. What type of current are you pulling?
Haha, it’s those logistics that will keep you from riding it for more than a few minutes…
I’m willing to bet 3-4 amps during steady state driving. It should just be the fuel pump and mega squirt, right? I don’t see anything in regards to feedback to the ecu…
I’m not running MS. That idea was scrapped months ago. I have a carb on it.
Strictly fuel pump, and it only needs to be able to run it for a little bit until the alternator kicks in. I mean, in theory, there will be fuel in the bowl, so I really don’t NEED a battery unless I run the bowl dry.
Maybe I’ll just have a connection for a li-ion battery pack and I’ll only just leave it disconnected until I need it, just to prime the pump. I sorta like that idea.
so do i.
A primer bulb from a honda lawn mower.
If the tank is above the carb then won’t it fill the bowl by gravity? My bike can drive down the street for 200 yards before it dies if I forget to turn the fuel on.
I don’t think it will make it through the pump, filter and regulator on gravity.
Well if you don’t run it with the fuel pump off then it should always be full, no?
Wait, why do you need a pump if it’s carb’d?
He’ll need around 5-7psi to run it if it’s carb’d
newman did you take a look at rc car batteries? The long skinny ones?
They also make lithium ion packs that are 4 AA wide
Yeah. Need a fuel pump to overcome boost in the bowl.
I’ll look at the RC battery, but I doubt hey can take constant charging.
Ah, gotcha. Yea I think you are going to need a little charging circuit if you are going to use anything other than a standard battery.
I think I am just going to make a “jump” connector that will allow me to power the fuel pump in the event of it running dry, and then use no battery.
How much power does it need to prime? you should do one of those hand cranks from a flash light :lol:
Newman, there are batteries that we used to use at the RV place to power Brake Controller units…not really sure if it will work, but I think was something like this:
edit- sorry, I just saw above you said these are too big.
haha. Well I don’t need to prime it all the time, just in the event that the bowl runs dry (like I run it out of gas or drain the bowl or something)
Running it out of gas will probably happen more than I want it to. I have a history with that. 