Best battery for 1275, rigid frame, 10.6:1

[Steve9]

Originally Posted by John Harper

I found this, looks like the 27AH Shorai on sale. I have the 24Ah one, but prices seem about the same as 3 years ago, even less. That's a surprise. That 27Ah puts out 405 CCA! Very close to a perfect world. Cheaper and more powerful!

https://www.batterystuff.com/batteri...xlh-sportster/

John

Seems the li/fe batteries have come down some in price

I love the strong cranking compared to the lead-acid batteries, especially with my dyna.

The lithium batteries are also going on 3 years old with no tender, I never got more than 1 1/2 years out of a lead battery in my dyna. I think the heat kills them.
Had similar stuff in my cars/trucks all my life probably due to heat but the lithium are way too much $ for that application

[gusm2]

Originally Posted by John Harper

There are plenty of lithium-iron batteries that will work. Just do some research.

I've been using Shorai FePO4 batteries for almost 8 years now. My 1991 conversion to 1250 turns over just fine.

John

I also use a lithium battery in my race bike ans while they have excellent starting power and light weight when there's a problem elsewhere it can quickly turn into a nightmare,
My regulator rectifier failed 2 weeks ago at the track, luckily near the startline where help and tools were on hand,
It was seriously overcharging and overheated the battery to the point the top blew off while still in the frame, I did manage to get it out before any major damage occurred but I did have to cut the cables

[Tomcatt]

Originally Posted by gusm2

I also use a lithium battery in my race bike ans while they have excellent starting power and light weight when there's a problem elsewhere it can quickly turn into a nightmare...

It was seriously overcharging and overheated the battery to the point the top blew off while still in the frame, I did manage to get it out before any major damage occurred but I did have to cut the cables...

EarthX LiFePO4 batteries (and some others) have internal Battery Management Systems (BMS) that prevent overcharging along with other protections.

Sounds like if you'd had a lead acid battery you could have had acid everywhere while trying to cut the cables...

[wrkdWS6]

I don’t think the battery is the issue. Many street 1275 setups have less cranking compression than stock. What’s your CCP?

I ran a Yuasa for years and now a Shorai lithium with my 1275. The Shorai is the only battery that I don’t get the occasionally hot start kickback with. Every other battery did with my 1200 and 1275 setups.

[Jfart]

Originally Posted by wrkdWS6

I don’t think the battery is the issue. Many street 1275 setups have less cranking compression than stock. What’s your CCP?

I ran a Yuasa for years and now a Shorai lithium with my 1275. The Shorai is the only battery that I don’t get the occasionally hot start kickback with. Every other battery did with my 1200 and 1275 setups.

I think my current battery is suppose to be 315 CCA. I’m sure it’s the battery. Same thing happened last year, was in a hurry, got the same battery “under warrenty”. Batteries plus were going to test the battery and then refund me but after the test they said the battery is fine. they weren’t testing the cranking amps. Only testing how much power it will hold. So then I ended up with two POS batteries for the same bike.

I had the equivalent battery in the GF’s 04 sporty (only mods are exhaust, intake, and jetting). Same thing happened over the winter with her bike battery. Both batteries were placed on a different charger battery tender that are two different brand tenders.

I ordered a Shorai and Shorai charger. Should be here within a few days.

[Steve9]

....and clean the ground just because

[Jfart]

Got the battery, charged it and installed it. Very impressive compared to previous battery. Turns over without any hesitation.

Now I’ve got to figure out different problem I was hoping I had fixed… i hadn’t fixed it.

Was in 2nd gear slowly rolling into the throttle. Right before the shifting point it’s feel like something slips and catches a second later. When it catches it comes with torque as if I’d popped the clutch. at this point I don’t know if the dog isn’t seated all the way, is it hopping out of a gear and into the lower gear?

Anyone know of any good write up or info on diagnosing what’s happening here?

Edit:Should I start a new thread for this? If so what section of the forum should it go?