Motobatt, Yuasa or ?

[alan s4]

Getting a bit chilly up here and the S4 is not firing up as quickly as before. Need a new battery - question is which one? I don't have power in my garage so it wont be topped up on a charger.

[Dukedesmo]

After having 3 Yuasas which would struggle to turn over my 916 (with raised compression ratio) unless 100% charged (kept on trickle charge), I bought a Motobat which has no problems at all even after a few months off the Optimate.

I also have (the same model) Motobatt on the Monster which has big-bore and high-comp pistons and it spins that with no bother.

The Motobat is (a little) heavier than the Yuasa but has more reserve, and a lightweight battery that doesn't start your bike is no use to anyone.

[alan s4]

Motobatt it is then. Does it fit the battery tray OK, seem to remember a thread saying it was larger that OE

[Flip]

I agree with DD, my original Yuasa lasted years and although always started the bike it never sounded like it was going to. When that one died after 10years I thought I'd replace it with the same- big mistake it lasted 18months under the same conditions!

So I bought a MotoBatt from Mad4Bikes (£55 inc delivery) and it's been great- I then bought a
9Ah one for my little race bike which is just as good and with my total loss ignition easily lasts a weekend race meeting without being charged.

For the Monster you need to order a MB16AU as that one fits in the tray okay with only a little re-positioning of the terminal leads as I remember- I think the other 16Ah battery they list is the one that is taller.

[Dukedesmo]

Does it fit the battery tray OK, seem to remember a thread saying it was larger that OE

Very slightly bigger, I had to make a new retaining bracket and remove the rubber tray from the 916 battery box but it fits fine in the Monster under-tank box.

Another bonus is that it shouldn't puke battery acid over the frame if the reg/rec fails and overcharges or if your bike falls over...

[fireman sam]

Have all bikes on them they are great

[alan s4]

Thanks for the replies - have ordered a Motobatt for £46.00 (inc delivery) - will report on findings

[He11cat]

Motobatt are fab!! Love mine !

[Flip]

A good price there but I forgot the S4's have a tiddly battery compared to that of the air cooled Monsters.

[jamiedan2009]

+1 for motobatt

[alan s4]

That's the new battery now fitted - exactly the same size as OE so fitted perfectly. Terminals are well designed and the leads fit far more securely. I'll be using the bike over winter and it won't be connected to a charger, time will tell, so far so good though.

[Darren69]

Yep I'm looking at a Motobatt for my 748. The S4 uses a smaller one and that on Amazon at least is £46 compared to £66 for the larger 916/early Monster CB16 type.

[damien666]

I Agree that motobatt give good cranking power, and mine served me well......
BUT..... when the reg/rectifier overcharged a few months ago, i ended up with the contents of the battery in the plastic tray.
I've taken the plunge (and expense) of going for a SHORAI lithium battery. It weighs about a quarter the weight of a regular battery. Should also last a lot longer ( time will tell)
For anyone interested , i bought it from www.carrotcycles.co.uk

[Darren69]

I appreciate that lithium seems to be the way to go, but don't you need a special charger for the lithium?

[damien666]

For the shorai there is a dedicated charger available, but a conventional battery charger is fine on trickle charge. ( charges up very quick)
I was told NOT to use an optimate type charger.

[Flip]

Lithium batteries are not good at all when used with the conventional charging systems found on motorcycles and cars etc. They are not suited to the charge cycle of a normal vehicle meaning they don't like the sudden discharge of a starter circuit and then the gentle charge from riding around for 'X' amount of time after.

They also don't do well left for long periods with a parasitic drain i.e: an alarm, clock, mileage memory etc. and you will definitely need a Lithium battery specific charger as they need to be 'exercised' about once a month- fully discharge and then fully charge right after (I even have to do this with the Scitsu Tacho on my little race bike). The reason you shouldn't use an Optimate type charger is because of the way they bulk charge, float and monitor a drain to check the condition of a battery during their charge cycle- Lithium batteries only need to do one thing at a time, be dis-charged or charged.

One other point of note for the Shorei batteries is the reason they seem such good value compared to other Lithium batteries is that they use cheaper components such as Steel terminals instead of Brass or Copper and therefore not such good electrical contact.

They are really best used for total loss type electrical systems found on race bikes etc. where there is no starter and their only function is to provide power for an ignition system and energise the coils.

As for the Reg/Rectifier failure that cooks a Lead Acid battery- do that to a Lithium one and be prepared for a BOoooM!

Lithium on a road bike?? Don't do it kids!!

[Darren69]

When I was told that you need a special charger for lithium, I did wonder how well one would cope with the bikes own charging system. So I won't be going with the lithium then, especially as I don't fancy anything exploding under the fuel tank! The AGM type do have better cold cranking power and last a lot longer than conventional lead acid too I think, so Motobatt it will be.

[Dirty]

The Shorai is lithium iron phosphate as opposed to lithium ion. Lithium iron phosphate batteries are far more stable and can be charged using standard chargers. Lithium ion batteries are the ones that can explode if abused. The charging system of a bike could, possibly, if the circumstances were right, make the ion type explode, perhaps.

[damien666]

when i changed the reg/rectifier, i upgraded to the mosfet type ( apparently far more reliable).
I also fitted an LED which constantly shows how the system is charging ( either under, correct or over charging, by changing different colours) for piece of mind.
My dads used a Shorai for several years, with no issues.

[Darren69]

I was just thinking, you'd probably need one of those mosfet type as they switch off, so you probably couldn't overcharge it