fooked battery?

Halal Tim

Club Member
advice needed please.

2014 street glide.
original battery. now 8 yrs old.

on the way to llandovery, the batwing volt gauge, which is normally reading 14V, was bouncing between 13.9 on tickover to 14.5 on the move.
no dash lights came on. bike ran fine, and started fine.

checked all the connections and earths, no difference.

just put an external voltmeter on battery.
12.7, without ignition switched on, dropping to 12.3 with ignition on, but engine not running.
bike running at about 2k rpm, and volt meter shows 14.
when i started the bike, volt meter showed a drop to 6v.

now, im not a sparky, and dont mess with electrics, as im colour blind.
but reading kiwi daves thread in tech tips, and trying to rember fuzz's advice,
can i safely assume the batterys fucked, and its not the regulator??

ta.
 
As far as I know, it should only drop to about 10 when you start the bike. 8 years is not bad. If it were me I'd probably get a new one. Especially, if I was going to the Super Rally.
 
Ian.
I am surprised the battery has lasted 8 years. Despite regular use of optimisers, 6 years has been the longest I have got out of an OEM battery.
Tony.
 
I've just had to replace a 2014 OEM battery on my Low Rider. At rest and off the Optimate it was reading 13v but was incapable of turning the engine over. I put in a battery from another bike and it started fine and the old battery wouldn't start the other bike. New battery now fitted and bike starting perfectly.
 
I've just had to replace a 2014 OEM battery on my Low Rider. At rest and off the Optimate it was reading 13v but was incapable of turning the engine over. I put in a battery from another bike and it started fine and the old battery wouldn't start the other bike. New battery now fitted and bike starting perfectly.
You might find that Optimate type trickle charges don't supply enough amps for these bigger batteries. The voltage is up there but not enough oomph after a long standing. (I'm quite prepared to be pointed out as wrong on this). They're OK for topping up whatever the alarm takes.
 
Do replace that battery with a brand new one. I prefer H-D batteries, even for my Shovelhead. But it's a free choice.

You can only test your charging system with a 100% known good battery. I always, as you may have read, trickle charge them for 24/48hrs before putting on the bike. They are never 'fully charged and ready to go, mate'' from the shop.

With an excellent battery, your multimeter will show you instantly if the regulator is working.
 
Cheers. Battery being delivered today. Will have it on optimate till sat am, then i will fit to bike, and see how we go.
 
I've just had to replace a 2014 OEM battery on my Low Rider. At rest and off the Optimate it was reading 13v but was incapable of turning the engine over. I put in a battery from another bike and it started fine and the old battery wouldn't start the other bike. New battery now fitted and bike starting perfectly.
Your Optimate, like mine, will show you all day long that the battery is ''fully charged''. Turning the ignition key to ON will be the absolute proof if it can hold a load, which is as vital as breathing is to you and me.

Thoresby is probably right, and I am certainly no electrician. I have no technical explanation as to why a battery damaged by a regulator or stator failure will show ''fully charged'' on the Optimate or similar charger, when it has been damaged to the extent it cannot take a load. You need a sharper mind than this dull mental block between my own ears to explain it.
 
I just factor it in the ownership. When they start getting dodgy I get a new one. But, always best to check there's no leak down.
 
Reading this thread has got me thinking about my battery.
I've got a Yuasa ytx20h-bs that is 9 years old now. It still starts the bike easily ('89 FXR) but you've got me wondering if I should be looking at replacing it soon.
Money is tight so,would the ytx20-bs version be up to the job,being 270cca as opposed to the 310cca of my present battery?
 
Is battery life determined by age or usage?
If you only started your bike twice a year and kept it on an Optimate, would it last longer than a bike that is regularly used? My Low Rider has done over 28k miles in the 8 years the OEM battery lasted.
Roach - Does your non-standard (Rev Tech ?) engine have a higher compression ratio than standard? If so I would be inclined to go for the most CCA's I could get, as I understand that it's the CCA's that actually get you going. (Disclaimer, I'm no auto electrician, I just read it in an article somewhere).
 
I agree with what you're saying Neil, I'm just wondering if I really need the extra amps.
 
Basically I will keep this as simple as possible, a battery is a device to store electricity and works by chemical reaction, the amount of electricity and it’s ability to release this stored electricity is determined by it’s construction, condition and what electricity has been inputted & stored.
So, all batteries are not the same, in construction, type and design, some function better for certain tasks than others.

The vast majority of batteries used on H-Ds are now AGM and designed to deliver a high ampage output for electric starter duty within a relativity small size, they are lead acid and sealed so you cannot replenish the electrolyte (The distilled water/acid mix) or have to top this up.

Most battery chargers and initial testing will be on the battery standing voltage, so if it reaches this, it will show as charged, however the capacity or rather ability to deliver a high ampage for starting may be impaired due to various reasons e.g. shorted cells, buckled plates, lack of electrolyte etc. so could only have 40 or 50% of it’s working capacity, in the old days the charge of a lead acid battery could be determined by taking the Specific Gravity of the electrolyte, but you could also still have the same capacity problems so no real test of condition.
A charger such as an optimate will do a test by switching off the charge and monitoring the voltage over a period of time, may even put a slight load on, so if the voltage does not drop within the limits, it will say it is good.

There are battery conductance testers that will test the internal resistance of a battery and give an indication of its condition and performance, these are however not infallible and can also sometimes show a battery good when it is not, however they rarely show one that is bad when it is not.

The real conclusive test is a practical load test, i.e. will it start and as detailed by KiwiDave many times and watch the volt drop.

A word of warning, it is not best practice to use one of those old Battey load testers, i.e. with and piece of corrugated metal to test a motorcycle AGM battery as these can easily draw what is an excessive current and damage the battery permanently!

What damages the battery, over charging, i.e. high constant current over charging or over voltage such as due to a faulty a voltage regulator/alternator, a full or near to full short circuit, (Back to the old battery load tester) or excessive load …and by far the most common, leaving the battery in a full or near full discharged state, most AGM batteries will lose most of or suffer a very significant reduction in capacity permanently if this happens and is left for some time i.e. Weeks!
These will mostly all initially boil off all the electrolyte, that you can’t replace and or buckle & sulphate the plates that will stop or hinder the chemical reaction.

AGM batteries are not like the old flooded lead acid batteries (the ones you could top up) that worked well on a charge/discharge cycles, this effectively works by using the charge cycle to cause gassing on the plates and dislodge any contamination on the plates, do this on an AGM and you can start to loose the electrolyte that can’t be topped up!

Best battery maintained for longevity, is regular use, if not, then left on a smart charger, to keep it monitored and fully charged.
Do not let it get deeply discharged. A battery is only as good as the plates in it, so you can have the same box but with not such good plates and materials thus cheaper, these will not last as long!

I would also say, most times you know when your battery is starting to fail as it will be slow or struggle to start, that is the time to check & test, never assume it's the battery, always check the charging system and connections first or you may well be buying a second battery quite soon!
 
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I agree with what you're saying Neil, I'm just wondering if I really need the extra amps.
If the cost difference is small go for the larger capacity as the battery will work less on the starter duty and even when slightly discharge have enough capacity to start without issue.
If it works leave it, Age is no indication of performance!
 
New battery came yesterday.
12.7 v out of the box.
Put it freestanding, on optimate overnight. 13.5 v this morning.

Ive left it on optimate, as im on duty again today. Will fit it tomorrow, and then see how it goes.

Thanks for everyones input.
 
Battery fitted.
13.5 with ignition off.
Drops to 10.5 when cranking over.
(It doesnt spin any faster than it did with the duff battery.)

Measures 14.1 at 2k revs.
Batwing gauge shows slight movement from 14 to 14.3 roughly.
But doesnt drop below 14, as it did with the duff battery.

Is this as it should be?
 
changed my 2013 103 streetglide battery this week for a H.D one from main dealers(Newmarket
£215.60
pricey but if it lasts as long as the last original one , nine years then worth it
 
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