Modern Vespa

Any recommendations for a 12v battery to sit in the Rally 200 tray nicely?

I have a lithium one which will fit sideways, but it looks a bit kooky.

My 6 v horn seems overwhelmed by the 12 volts. Is there a way to rig the 6v horn to work?

I know the other options.

thanks

Gazoo,

Add a resistor in series with the horn. If you know the current flow of the 6v horn, its easy:

R = (Vs-Vf)/I,
R = (12-6)/0.5 (guess)
R = 12 ohms

W = RI
W = 12 ohms *0.5 amps
W = 6 watts (round up to 10)

R=resistance
Vs=supply voltage
Vf=forward voltage
I=current
W= watts

https://www.digikey.com/en/products/detail/te-connectivity-passive-product/THS1012RJ/2366855

Thank you.

I am sketchy with electronics, so I appreciate the help and thoughtful explanation. Just to confirm, let me know if this sketch makes sense. Also, not sure how we know the current (I) of our system. Is that dependent on the battery?

With regard to Amps, I have a new battery that is rated 105 cranking amps and 45 cold amps, 18wtt hrs so 1.4 AH so not sure if that plugs into this equation for a different level of resistor or what? Perhaps I need to buy a different battery?

I am still looking for advice on which type of battery would be best for my situation. The battery I have is a Lithium Powersport Battery, which I can fit sideways into my battery holder.

I also have an old CASIL 12v 4AH battery which is a cheaper version and heavier possibly less powerful?, ( i have no idea)

I get the resistor idea, I think.... but now need to put in the proper, or possibly best battery to run a powerful horn, lighting system.

thank you

Your existing battery is fine. As is your drawing. The current draw is based upon the horn. I think .5 amp is pretty close.

locked in that you've got two threads about the same thing.