Hi folks,

I am struggling to find the original RS battery dimensions, having bought an RS in pieces the battery is missing so I cant measure it to find a replacement that will fit exactly.

Thanks FrustratedRS

Hallo!

The only size you need is the length up to 181mm for ALL Ks, (175mm is standard) the rest will fit anyway.
A modern non acid batterie is always slimmer.

If you are more interested just search in eBay for K75 100 batterie.
My has 18amp and the price was 36€! is from the solar industry.
Lead flowing Battery 181x76x167mm, no more dripping :-)
With acid batteries you only have problems, dripping, maintenance etc.

Cheers


For more info check YouTube! this Danish guy made some nice videos
BMW K75 How to check the battery and generator, and connectors
https://m.youtube.com/watch?v=-RuvmFR60Gc

Thank you chocolate,

Seems Confused is the correct username for me after all

The issue on length and width. You give the width as 181mm (175 Being standard )

The 181x76x167mm, am I correct in assuming that length is longer than width? which means 181 is the length and 167 is the width or the height?

Thanks

You are correct, I did a mistake!

My Batterie
Lenght 181x width 76x hight 167mm


I guess the width can be more than double, there is a lot of free space left.


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This is a other Batterie from eBay, check the size
http://www.ebay.com/itm/Yuasa-YuMicron-Battery-53030-BMW-K-100-RS-1984-1992-/321985984500?hash=item4af7dc37f4:g:~BQAAOSwFqJWo5Yk&vxp=mtr

Cheers

Thank you ....

I use a Motobatt MBTX30U which is L 166mm x W 126mm x H175mm.  It's a sealed AGM type so wont leak.  The height is about 5mm higher than standard for the K1100, K100 & K75 they also use a smaller battery which is the one Choco said.  5mm higher is very marginal on the screw length and is very difficult so I use some 6mm threaded rod and lock nuts at the base and nylocs at the top.

If the shops you're searching have cross reference charts, the OEM battery numbers are: full sized lead/acid 61 21 1 459 650. Slimmer sized Gel 61 21 2 346 800. Both will fit K battery trays. The la flaca (slim) version is 19Amp while the L/A el gordo (fatty) is 30Amp.

Other numbers to search for are the 'industry standard numbers' which are 51814 or 51913. In my Aussie RS I use Motobatt's excellent, yellow AGM version of either of these two reference numbers. Its dimensions are: L 183mm (7.2"), W 80mm (3.15"), H 170mm (6.69")

Just found a picture of The Batterie tray.
The Kung Long Batterie is a inexpensive non acid batterie.

WP 18-12, 12 Volt, 18 Ah, 167X180X75mm

34.99 US Dollar (eBay South Africa) that's even cheaper then in Germany
http://www.ebay.com/itm/Kung-Long-WP18-12-12V-18Ah-UPS-Battery-/281342287045?hash=item41814e9cc5:g:jGsAAOSw-jhULdM5

You will find better for the Ks, but nothing as cheap and good as the Kung long batterie! :-)

Here you can see the batterie tray in black on the gearbox
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Cheers

I don't have any dimensions at the moment but caution you on the height of the battery. At one end of the top bracket that holds the battery in place is a small concave indent that also helps secure the radiator expansion bottle. If the battery is even a little bit higher than the original equipment then two things may happen:
1. The long screws inserted in the top metal battery bracket and that thread into the battery tray may be too short.
2. The top of the radiator expansion bottle will not fit snugly into the indent of the bottom of the top bracket that holds the battery in place.
There are workarounds for both of these issues, one being longer threaded rod to replace the existing long threaded battery bolts (already mentioned) . You can also slightly bend the top battery bracket down to catch and secure the top of the radiator expansion bottle.

Shep

OEM battery is a Yuasa 53030 (formerly Y60N24-AL-B, now discontinued). OEM battery dimensions are 186mm L X 130mm W X 171mm H.

Thanks to everyone I have narrowed it down to a few suppliers in Cape Town

I only have one more dilemma, since I don't have the original battery I have no idea which side the positive terminal has to be or does this not matter?

Much appreciated....

Terminal type and orientation matter.  Positive on the left side of the bike facing forward; negative on the right.



The black bump is the position of the drainage hole on a wet cell battery, but if you buy an enclosed battery, this will be missing.



Isometric, front, side and top views of OEM battery terminal post.

Thank you Robmack

further to Shep's suggestions on how to secure your coolant expansion tack , I fitted an Odyssey PC680 AGM battery , to help secure the tank the suggestion was to simply flip the battery bracket over ( and refit the rubber do dad from the reverse side ) this moved everything about 5mm down ( suggestion was from BMW owners of America site )

hope this helps

John Re

Thanks John

You want the MBTX30UHD. It's slightly taller than OEM which may give a few problems with the tiedown bar where it holds the overflow tank in place. It's not a huge problem to solve; many of us are using that particular battery. I turned the tiedown over which took up sufficient of the gap not to worry about it.

There are many threads on the forum where people write specifically about the model MB51814. I don't want a taller battery.

This is the one I recently bought (from motorworks). 
The dimensions are good for fitting with the existing securing ironmongery. The price made me choke on my beer, but other than that, a good fit.



I have the UHD version on Gretel but it is a bit of a faff securing as it is slightly taller.

LifeGuard wrote:There are many threads on the forum where people write specifically about the model MB51814.

All the posts I've read indicated the MB51814 fits the cradle. Instead being concerned about the Motobatt's fit, consider shopping for a tape measure that reads 183 across that span.

Personally, I'll be dipped if I ever spend that much on a Brick battery. The one I used for nine years when riding daily until winter never even needed to be attached to a charger—including during winter storage. It was simply put to bed in the Brick with a full charge from riding and then its ground cable was detached from the transmission. The Brick started right up in spring year after year so I bought another two years ago when I didn't want to push my luck any longer.

Ok, following up on that post: https://www.k100-forum.com/t4453-battery-recommendation#46987, Motobatt MB51814 battery fits.

Ok, I finally bought the MOTOBATT MBTX20UHD battery and 3d printed special spacers so it wouldn't "fly around" in the original tray and would have the correct dimensions. I hope that the 320 cold cranking amps is not too much. 

Laitch wrote:

LifeGuard wrote:There are many threads on the forum where people write specifically about the model MB51814.

All the posts I've read indicated the MB51814 fits the cradle. Instead being concerned about the Motobatt's fit, consider shopping for a tape measure that reads 183 across that span.

Personally, I'll be dipped if I ever spend that much on a Brick battery. The one I used for nine years when riding daily until winter never even needed to be attached to a charger—including during winter storage. It was simply put to bed in the Brick with a full charge from riding and then its ground cable was detached from the transmission. The Brick started right up in spring year after year so I bought another two years ago when I didn't want to push my luck any longer.

I was fiddling around with my well-used 24V electric mower the other day, the kind you push into the shed in October or November and forget about 'til springtime, charging only throughout summer with use. Well, looking at your 'cheap' battery link I see this old mower has two of this very (Asian) brand inside strapped in parallel with a hand-scribbled install date of May, 2008. Bloody hell! They're only now not holding a charge well.

Sixteen years. 16. Six-teen.

I can get them locally for US$72 the pair plus 9.8% tax.

The last (again, cheap) battery I bought for one of my K1200RS was just under $50 delivered. Fit last October it sat all winter untethered to a charger of any sort. It cranked with gusto and the bike fired first crank the other day.

I've reliably been a BMW (5 - 7 years), old school Odyssey (14 years) or Motobatt (irregular due to storage in OZ) user, with the occasional lithium, for yonks. Now I'm on a pensioner's budget, no longer tempted by the dealership stock I had my hands on, I reckon I might’ve been spending too much. 

LifeGuard wrote:Ok, I finally bought the MOTOBATT MBTX20UHD battery and 3d printed special spacers so it wouldn't "fly around" in the original tray and would have the correct dimensions. I hope that the 320 cold cranking amps is not too much. 

Hi Lifeguard, where did you get the 3d printed special spaces from?

Blue_Ian wrote:Hi Lifeguard, where did you get the 3d printed special spaces from?

I made by myself

A former colleague of mine, more adept at computery things than me, was an early adopter of 3D printing. Each time I visit him he's fabbed up some truly intricate pieces for his hobby classic cars, appliances that need a new bit you can no longer buy, toys for his young son, or additions to his collection of older motorbikes. Amazing stuff.