AGM battery for XJ650 stock battery box..

Hey guys,

I searched on this first but didn't find my answer.

Looks like my battery has finally bitten the dust. I'm trying to find an AGM that will fit in the battery box and also provide enough cranking amps.

Can anyone recommend? Does anyone know the min required cranking amps for the xj650 maxim 1981?

 

I don't have the spec's at hand so cannot help there but if you take the dead soldier to your local NAPA store they can get you the right one at a decent (fair) price. They likely will have to order it but I have had great luck with them getting ordered bits the next day. Just be sure they get you the AGM as they have lead/acid also. Good Luck.

 

Your battery case size is 12A, with the terminal code A2 so you can make your choices based on that. Any battery with 12A-A2 in the middle of the code will physically fit and have the terminals in the correct orientation.

 

Thanks k-moe !

 

Can anyone explain amps per hour... I get CCA but Ah is confusing to me.

 

Sustained power over a one hour period.

 

ah so 9Ah would mean it can provide 9amps constantly over 1 hour?

What should I be looking for as a minimum for the XJ650?

 

Amps per hour is the amount of current that can be drawn from the battery over one hour's time before the battery will go flat.

Typically motorcycle batteries are rated at a 10 hour discharge rate, so with the code I gave you earlier we can figure how many amps can be drawn from the battery over 10 hours before it goes flat. The 12 in the above code is the total number of amps that can be drawn over 10 hours of discharge. 12/10 = 1.2 which means you can draw 1.2 amps continuiously for 10 hours, at which point it wll be fully discharged (the voltage wil also decrease over the period of the drawdown).

If you really wnat ot understand batteries, go here: http://www.batteryuniversity.com

There really isn't any reason for having a battery that is rated for more than the required amp/hour rating (12 for XJs) unless you intend to use it as a power source while the engine isn't running. The limiting factor for accessories is the current capacity of the motorcycle's charging system, not the battery's amp/ hour rating.

 

thanks - just trying to source an AGM and it's proving very difficult to find one that fits... that code you gave me doesn't appear to apply to AGM's from what I can find.

Anyway - looks like I'm just going to do a like for like and replace it with a wet as much as I don't want to it's proving extremely hard to find an AGM that will fit, provide the right CCA, Ah and also have the right polarity.

 

what about this one?

http://www.scorpionbattery.com/powerspo ... yt12c.html

 

That one works.

"Replaces

Yuasa YB12A-A, "

 

You continue to impress me k-moe

 

Not at all. Unless a battery is rated for a one hour discharge (which is rare to find) you won't get an hour's use.

A math intensive, but complete explanation as to why.
http://all-about-lead-acid-batteries.capnfatz.com/all-about-lead-acid-batteries/lead-acid-battery-fundamentals/peukerts-law-and-exponent-explained/

 

I just have too little money to let other people fix things for me, and I love learning about how things really work.

 

So on an AMG there is no exhaust on the battery so the last digit shouldn't matter right?

PAGE 2..here..
http://www.batteriesdirect.com.au/files ... 9950_2.pdf

 

There actually is a vent, but it's tiny and doesn't need a hose hooked up to it. So, yes, that number dosen't matter.

 

So after much feckin around I found that a lot of the AGM batteries that "say" they are a replacement for the stock don't actually fit.

They probably fit in the housing but you can't get them through the V in the frame cos they are too deep.. that extra 1/2 inch make a big difference. I have to say tried several angles and ways but no dice...

So - anyway - after a lot of research and google-fu I found one --

http://www.motobatt.com/MB12U?search=MB12U

Had to drive 120 miles round-trip for it but it's a damn near perfect fit and seems to be a very good make with great reviews. Pretty sold 160 CCA and 15Ah.. not bad for $80.

 

I had to rotate mine to fit it in. Even the flooded Yuasa replacement has to be inserted perpendicular to the frame rail and rotated in an arc to fit into place.

Glad to hear that you got a battery.

 

Thanks moe,

...and thanks for answering my dumb questions... some day I'll come up against something with this bike that's not a PITA..