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Motorcycle Battery FAQ


1.Do I have to charge a motorcycle battery? 
Motorcycle batteries are dry charged to about 80%. If you don't give the battery a top up charge (3-4 hours) the battery will only ever be 80% efficient (which will greatly shorten the

2.Can I use a car charger or a high rate charger? 
NOOOOOOOOOOO!!!!!!! A car or high rate charger will force a higher rate of charge into the battery, which can result in permanent damage to a motorcycle battery. Because of their size, motorcycle batteries cannot take the same high charges or abuse that car batteries can.

3. Why do I need to top up my lead acid battery? 
Lead acid type batteries use electrolyte (battery acid) which is a mixture of water & sulphuric acid. When the water evaporates this makes the acid concentration stronger. If the acid becomes too strong it will corrode the batteries internal components which will cause loose particles to collect in the bottom of the battery & short it out

4. What is the popping or fizzing noise I can hear when I charge my battery? 
As your battery charges, the electrolyte (battery acid) reacts with the lead plates inside the battery to produce lead sulphate & in the process the electrolyte releases some of it's hydrogen, which causes bubbles to be produced inside the battery which can produce a popping or fizzing noise (similar to the bubbles in a lemonade bottle!). This noise can also be produced for a short period after the motorcycle has been ridden as the chemical reaction which produces electricity is still occurring. BUT, the noise should be fairly quite, so if your 50 meters away from your bike & it sounds like someone has put a firecracker under your seat, our advice would be 'RUN LIKE F**K!!!'.

5. How can I check if a motorcycle battery is fully charged? 
The best way to check a battery is with a volt meter. A healthy 12 volt battery should be between 12.5 & 13.5 volts & a healthy 6 volt battery should be between 6.5 & 7.2 volts (although this is only a guideline, once a battery drops below 12.4 volts it will struggle to start most bikes).

6. My motorcycle battery has gone flat, can I recharge it? 
Although motorcycle batteries are being constantly recharged while the engine is running, they are only receiving a 'top up charge'. Motorcycle batteries are not rechargeable like mobile phone batteries, which run almost completely flat then can be recharged. Once a motorcycle battery drops below the level required to start a motorbike (usually around 12.4 volts), it means that the battery is starting to fail.

7. How long does a motorcycle battery last for & why don't they come with long warranties like car batteries?
Most motorcycle batteries are at their best for about 3 years. Because of their size, motorbike batteries don't last anyway near as long as car batteries so warranties tend to be alot shorter.

8. When I put the battery on the bike, which terminal do I connect first? 
Always connect the positive (+) or red terminal first. Make sure there are no flammable substances (i.e leaking petrol!) around the bike as connecting the battery can produce sparks which can ignite flammable materials.

9. What is the white stuff that collects in old batteries? 
The white stuff is lead sulphate which is the same compound the lead plates in the battery turn into when they discharge. Lead sulphate is a crystal & can destroy a battery if allowed to build up. This process is called sulphation.

10. What causes sulphation? 
In normal battery operation, lead sulphate never has much chance to build up on the plates because the charge cycle returns the sulphur back into the electrolyte & turns the plates back into lead. But a battery that discharges too deeply can develop sulphation. Another cause of sulphation is low fluid or electrolyte level in the battery. When the fluid level drops, the lead plates are exposed to air. Under these conditions, the lead plates will oxidize & sulphate & the battery will no longer hold a charge.

11. How do I keep my motorcycle battery from sulphating? 
Make sure your motorcycle's electrical & charging systems are functioning properly so that any charge lost during starting or by the running of lights or accessories is replaced. Keep the battery terminals clean & disconnect them if possible when the motorcycle is in storage. Most importantly, charge the battery with a motorcycle battery charger regularly if the motorbike isn't being used regularly to maintain a healthy charge in the battery. 18. If I disconnect the battery terminals, will the battery still go flat? A battery will still carry on discharging, even if it's not connected to a motorcycle although it will lose it's charge at a much slower rate.

12. Why are some batteries bigger than others?
The size & number of lead plates in a cell depends on the output of the battery. The more plates in a cell, the bigger the battery & the more current it produces & capacity (amp/hours) it has.

13. How tight should the battery terminal bolts be?
Use a screwdriver or spanner to make sure that the bolts are as tight as they can possibly be. A common problem that occurs with bikes (even brand new ones!) is that the battery terminal bolts are not tight enough (basically, when you think you've tightened the bolts up enough, tighten them a bit more to make sure!). Battery terminal bolts that are not attached securely will work loose & cause erratic & rough running problems as well as starting problems.

14. What is battery acid & is it corrosive? 
Battery acid (or electrolyte) is a mixture of sulphuric acid & distilled water & is highly corrosive, please handle with extreme care. Try to avoid contact with skin & eyes & don't put left over acid in empty lemonade bottles!

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