Only one cylinder firing

[farmall]

Bring your old battery when buying a replacement to confirm fit. That avoids relying on how different battery makers confusingly list their products.

More CCA is always better.

[thrash89]

My bike came stock with a 200 CCA battery. He said any higher CCA than that and the battery won’t fit because of the size. Any input here?

[farmall]

It that''s the max for that battery box then go with it. More CCA may be available from specialty batteries but I avoid specialty anything that's disposable.

[JBinNC]

My bike came stock with a 200 CCA battery. He said any higher CCA than that and the battery won’t fit because of the size. Any input here?

That's one reason you are having problems.

Jim

[thrash89]

I don’t think they would put that battery in there if it was going to cause problems. A bigger battery won’t fit. I mean when the battery was good it would crank over and start with ease

[Tattooo]

He said any higher CCA than that and the battery won’t fit because of the size. Any input here?

Get the same size battery in the biggest CCA.......... That's all you can do............

[thrash89]

Yeah I had the same thought

[thrash89]

Just put in the new battery. And the front cylinder still doesn’t fire.

Do you think the old battery could have shorted out the new crank sensor?

[thrash89]

Also, when I crank the motor with the spark plugs out, the rear cylinder spits out a shit ton of gas

[Tattooo]

Do you think the old battery could have shorted out the new crank sensor?

Could be.............

[Tattooo]

Also, when I crank the motor with the spark plugs out, the rear cylinder spits out a shit ton of gas

Put in new plugs and try again.............

[farmall]

Electrically there's no reason for a battery failure to take out a crank sensor. It could affect the charging system by drawing too much current if shorted internally but usually doesn't.

Describe that "shit ton of gas" in detail. Puffs of mist or lots of droplets?

To remove all doubt about your Thunderheart if you get stuck you can contact their tech support and probably mail it to them to bench test.

[thrash89]

I figured out the issue, I took my carb and intake off and replaced seals with extra ones I had. Started right up and ran great. Then it started getting a bad air leak. So I replaced them again with an extra set. Again fired up both cylinder but still getting a bad air leak. My seals are not sealing for some reason (I have replaced intake seal on this bike before with no issues in the past, so it’s not an error on me) they just won’t seal right and I can’t figure out why. I’m thinking the Harley dealer gave me the wrong seals????

[thrash89]

Puffs of mist but like, a lot of mist

[Tattooo]

I’m thinking the Harley dealer gave me the wrong seals????

Post pics of your seals and a pic of your intake between your heads without any seals............. How much of a gap do you have between them?????????? The intake and heads that is.............