Wildguzzi.com
General Category => General Discussion => Topic started by: DaGootz on September 29, 2025, 09:49:43 PM
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I'm picking up a 1974 Eldorado Police bike this Wednesday in Baltimore. It is missing the battery and I'm having one heck of a time finding a "round post" battery for it. I ordered a 12v 30Ah motorcycle battery just so I have something to put in it while I sort the bike out, but for the life of me I can't find anywhere that carries a battery like I see in many Eldo's. What am I missing? Form the pictures it's missing the side panels, which I already located but I can see the battery cables and they are of the automotive type. Can anyone guide this Guzzi Noob to the correct battery please...and thank you.
BTW- I know the battery I purchased is going to be smaller in the battery tray and has the flat post, but the specs are correct.
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I don't have a specific recommendation, but a lot of folks use lawn tractor batteries. I would think some of them would have round posts (I know my Dad's 1969ish Cub Cadet had round posts).
Or- if that doesn't work, get some flat connector wires? The ground just goes to a transmission bolt and the hot goes to the starter.
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I don't have a specific recommendation, but a lot of folks use lawn tractor batteries. I would think some of them would have round posts (I know my Dad's 1969ish Cub Cadet had round posts).
Or- if that doesn't work, get some flat connector wires? The ground just goes to a transmission bolt and the hot goes to the starter.
I did start to check into a tractor battery but from what I was reading most of those were deep cycle and a deep cycle is designed as a "starter" battery, so the cells are designed to take a charge from a battery charger then you can run it till it dies, then charge it again. Whereas a car or motorcycle has a constant charge running through it. Something about plate thickness affecting a constant charge, so they're best for vehicles without a charging system. I'll give them another look though. Thanks for your input, much appreciated.
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Look for a U1 or U1R ( posts reversed).
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Look for a U1 or U1R ( posts reversed).
Thanks John!
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I did start to check into a tractor battery but from what I was reading most of those were deep cycle and a deep cycle is designed as a "starter" battery, so the cells are designed to take a charge from a battery charger then you can run it till it dies, then charge it again. Whereas a car or motorcycle has a constant charge running through it. Something about plate thickness affecting a constant charge, so they're best for vehicles without a charging system. I'll give them another look though. Thanks for your input, much appreciated.
Deep cycle batteries are used as RV house batteries to power the electrical appliances off grid (also boat trolling motors, golf carts, etc). Deep cycle means they can be drained much lower in between charging cycles than a battery designed for engine starting. True deep cycle batteries caution against using the battery for starting an engine as the plate structure is not designed to deliver high amperage required for cranking an engine.
There is a class of dual purpose batteries for those that want one battery on their boat. The battery will crank an engine and take a deeper drain in between charges than a battery that is only for cranking. It is not as deep cycle as true deep cycle batteries.
But for the bike you want a standard starting battery. It spins the engine for 3 seconds then it is on charge until you stop the engine. That battery delivers a burst of amperage. From then on its only smoothing out the voltage from the alternator. That is what lawn tractor tor batteries do. They are cranking batteries. Most any lawn tractor incorporates an alternator on board if it has electric start so no need for a deep cycle or or combination battery for them, or your bike.
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Maybe start here and select "B" for battery.
https://www.thisoldtractor.com/moto_guzzi_loopframe.html (https://www.thisoldtractor.com/moto_guzzi_loopframe.html)
Patrick Hayes
Fremont CA
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The original battery had small "automotive" type posts, no battery with those is currently available. If it has battery terminals for that, then it needs new cables anyway, since they are 50+ years old.
It's possible that the owner fitted a first generation Mazda Miata battery, which has "normal" sized automotive posts. This is one of my favorite batteries as it fits the battery frame very well, only requiring that two plastic tabs be trimmed away.
https://www.batterymart.com/p-12v-mazda-miata-battery.html
(https://i.ibb.co/JTMc4Cp/MAR-8-AM-U1-R-fullsize-400x400.jpg) (https://ibb.co/JTMc4Cp)
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The original battery had small "automotive" type posts, no battery with those is currently available. If it has battery terminals for that, then it needs new cables anyway, since they are 50+ years old.
It's possible that the owner fitted a first generation Mazda Miata battery, which has "normal" sized automotive posts. This is one of my favorite batteries as it fits the battery frame very well, only requiring that two plastic tabs be trimmed away.
https://www.batterymart.com/p-12v-mazda-miata-battery.html
(https://i.ibb.co/JTMc4Cp/MAR-8-AM-U1-R-fullsize-400x400.jpg) (https://ibb.co/JTMc4Cp)
Thanks!
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Farm & Fleet has lawn tractor batteries with round posts. These are not "Farm Tractor batteries" they are lawn mower batteries. And as mentioned a U1 or U1R type.
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Farm & Fleet has lawn tractor batteries with round posts. These are not "Farm Tractor batteries" they are lawn mower batteries. And as mentioned a U1 or U1R type.
Thanks!