has anyone tried using a 4AH battery in their Passport?

bob66542

Member
I recently went to a 4ah battery in my CT-70 using advice thru the forum here, it seems to work fine, and is $10 at Walmart- so I began to wonder if one of these would also work in my 81 passport, as long as I didn't try to use the electric starter- it kickstarts easy. I don't want to blow my headlight, as they are pricey. has anyone tried this?
 

red69

Well-Known Member
AH is the capacity of the battery and what it can deliver over a period of time. The voltage will determine whether or not your bulbs will go south. Use a 12 volt battery in a 6 volt system and you'll be replacing bulbs and maybe other components. On the other hand, use a battery with an Amp Hour rating higher than what is recommended and your system may not be able to charge it to its rated capacity.
 

bob66542

Member
yes, you are absolutely right, I didn't specify that its a 6 v. the6v 4 ah batt, which works great in a ct-70 that is kick only, is way below the spec'd AH for a c70, because of the electric start. I'm just wondering if anyone has run one in a c70.
 

69ST

Well-Known Member
From what I've been told, these batteries aren't the greatest with electric starters. There are questions regarding the charge rate and peak cranking amps they can deliver.

There's nothing wrong with going for more charge capacity; that could even get you "over the hump", IOW compensate for the slow-motion nature of these batteries. The alternative is going with a newer LiFePo (lithium-iron) battery; those are pretty impressive. The downsides are cost (and they are pricey) and potential for an electrical fire (though that's still an unknown) due to overcharging or/and physical damage. These bikes are hostile environments for electrical components.

IMHO...the bottom line remains the same "what works, works". At the price, what've you got to lose? As long as you're satisfied with the results, I'd call it a successful result. If that only works out because you rarely, or never, use the e-start...it doesn't matter. FYI, though I've never had an e-start engine in one of my CTs, I did run a partial-loss 12v system, supported with a 12v/5.0ah SLA battery. Never ran out of headlight power, as I never rode more than 2 hours, at a stretch, after dark. The only downside is that DTRLs were not possible. I ran that setup for 15 years and better than 20,000 miles, before going to full-wave 70W/12v electrical system and all LEDs. The point of these ramblings is the first sentence of this paragraph...and the fact that there can be many "correct" setups.
 

bob66542

Member
From what I've been told, these batteries aren't the greatest with electric starters. There are questions regarding the charge rate and peak cranking amps they can deliver.

There's nothing wrong with going for more charge capacity; that could even get you "over the hump", IOW compensate for the slow-motion nature of these batteries. The alternative is going with a newer LiFePo (lithium-iron) battery; those are pretty impressive. The downsides are cost (and they are pricey) and potential for an electrical fire (though that's still an unknown) due to overcharging or/and physical damage. These bikes are hostile environments for electrical components.

IMHO...the bottom line remains the same "what works, works". At the price, what've you got to lose? As long as you're satisfied with the results, I'd call it a successful result. If that only works out because you rarely, or never, use the e-start...it doesn't matter. FYI, though I've never had an e-start engine in one of my CTs, I did run a partial-loss 12v system, supported with a 12v/5.0ah SLA battery. Never ran out of headlight power, as I never rode more than 2 hours, at a stretch, after dark. The only downside is that DTRLs were not possible. I ran that setup for 15 years and better than 20,000 miles, before going to full-wave 70W/12v electrical system and all LEDs. The point of these ramblings is the first sentence of this paragraph...and the fact that there can be many "correct" setups.
 

bob66542

Member
i'm going to give it a try. As I said, it kickstarts easy. I know that it wouldn't operate the electric start. I just was worried about possibility of blowing out the headlite
 

69ST

Well-Known Member
As far as I am aware, your HL is AC powered and only while the engine is running, same as every model other than the CL70. The sealed AGM battery should be fine for everything except electric starting...better than OE, in fact. If you're okay with kickstarting, I think you'll be happy with the results, especially the added durability & absence of electrolyte leaking.:):yellow70:
 

bob66542

Member
took about an hour to install, had to rig a way to secure the smaller battery. used a piece of 3/8 threaded rod into an existing hole on the left side behind the side cover, nutted on both sides, and a nylon, fender washer and locknut/washer to secure the battery, and sticky backed foam to cushion the batt. put about 40 mi. on it, works great!
 

bob66542

Member
4ah. w:stud.jpg 4ah batt. connections..jpg 4ah. installed.jpg thought id post pic's of the installation
 
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