BMW R1200RT/R1250RT Forum

DaygloDavid wrote:The Part No. for the Battery on a 2012 Twin Cam is 61 21 2 346 800 & costs £136 from BMW (11/04/2014).

Euro Parts currently have a 20% discount offer, this battery is an equivalent to the BMW one at half the price.

http://www.eurocarparts.com/basket

Having spoken to Exide UK, it has been confirmed that they make the same battery for BMW.

"BMW stick their own label on it & charged twice the price."

The BMW battery may have a 2 year warranty, I'd be surprised if the Exide one failed after 1 year, if it did, you could just buy another one at that price.

Been speaking to MDS Battery Ltd, they offer an alternative to the Exide GEL battery.

The battery is made by Yuasa & is of the AGM type, at £50, it's certainly worth looking at as an option.

http://www.mdsbattery.co.uk/shop/produc ... oupid=9079

How to Prep Your Motorcycle Battery, https://www.youtube.com/watch?v=Xpg10yp4duo

DaygloDavid wrote: This looks like the Battery for the LC, Part No. 61 21 8 531 121, made by Exide.


Re: Replacement Batteries

I see it states a charging rate of 1.6 amps 5/10 hours but also says it's a 16AH ie it should be charged at 1 amp for 16 hours why is this. Personally I would never charge any battery at more than 1 amp per hour.

I just plug in the recommended charger and let it get on with it. 

futterweasel wrote:I see it states a charging rate of 1.6 amps 5/10 hours but also says it's a 16AH ie it should be charged at 1 amp for 16 hours why is this. Personally I would never charge any battery at more than 1 amp per hour.

I've always been led to believe that the charging rate should be 10% of the Ah. In this case, 10% of 16Ah is 1.6A x 10h.

An old Haynes manual for my 1980 XJ650 backs this up, 14Ah = 10h @ 1.4A & 12Ah = 10h @ 1.2A.

The Haynes manuals for both pre-LC RT's recommends a max. of 1.5A, the GS battery is 14Ah, whilst the RT is 19Ah.

The max. output of the BMW Motorcycle Charger is 2.5A, http://www.bmw-motorrad-store.de/lanota ... ions_1.pdf

DaygloDavid wrote: I've always been led to believe that the charging rate should be 10% of the Ah. In this case, 10% of 16Ah is 1.6A x 10h.

An old Haynes manual for my 1980 XJ650 backs this up, 14Ah = 10h @ 1.4A & 12Ah = 10h @ 1.2A.

The Haynes manuals for both pre-LC RT's recommends a max. of 1.5A, the GS battery is 14Ah, whilst the RT is 19Ah.

I would not believe any thing written in a Haynes manual. I have found instructions in them that if followed will lead to seizure at best and major engine failure. If you charged that bmw battery at 1.5 amps for ten hours it would be sizzling like a frying pan.

This is building into a Christmas version of "how much pressure should I put in my tyres" 

RTman10 wrote: This is building into a Christmas version of "how much pressure should I put in my tyres"

Does that depend on how much Oil you use?
:enjoying: :alas:

I considered mentioning oil as well but thought better of it. The can of worms is now open again.


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futterweasel wrote:If you charged that bmw battery at 1.5 amps for ten hours it would be sizzling like a frying pan.

Unless a fixed output charger is used, the battery wouldn't be being charged at 1.6A continually for 10h.

On the battery, BMW recommend a quick charge of 8A for 1h.

Perhaps it's a ploy by BMW to sell more batteries.

On most intelligent chargers, the current is automatically reduced as the battery voltage (charge) increases.

Which battery charger do you use?

Am I missing something here? What's wrong with BMW approved Battery Charger and BMW approved Battery? ???

Mike wrote:What's wrong with BMW approved Battery Charger and BMW approved Battery?

There's nothing wrong with the BMW stuff, except IMO the price, when perfectly good alternatives for both are available.

It would seem that having spent up to £16K+ to buy it owners go into eco mode to maintain them.