T H E  O L D  G R E E N  B E E M E R
RIDING A 1974 BMW R90/6 FLAT TWIN



REVIVING A WEAK BATTERY


( Be warned: this is highly experimental and at your own risk )


Two and a half years ago the battery of my trusty R90/6 was becoming somewhat weak.
Coincidentally, on the web I read an article about someone who prolonged the life of
his golf cart battery's with the help of Epsom salt. Having nothing to loose I thought
let's
give it a try, and so I got myself a bag of Epsom salt crystals. I found the stuff
is
used in the agricultural business, so that's where you can find it cheap. What I
did was the following, in a pan I warmed up about 500 cc of distilled water and
disolved about 10 tablespoons of Epsom salt crystals into it. The water was
pretty much saturated at that point. Next, with the help of a battery Hydro-
meter I removed all the acid standing above the lead plates of each cell
and replaced that with the same volume of Epsom salt solution. A day
hooked to the charger was what followed and yep ... cranking power
was back online and still is. There are no guarantees in using this
recipe, but it seems to be worth a try ... it keeps me going till now.






A pinch of Epsom salt can makes all the difference between riding or walking.
When the above discribed method doesn't yield good results, try to wake
the battery up by charging / discharging / charging / discharging. How?



AND ... ACTION!

For the resourceful Die - Hard battery rescuer only.
And also highly experimental and at your own risk.



A Lead / acid battery doesn't like to be dormant for longer periods of time and
needs action to stay healthy.  With action I mean it wants to be charged and
discharged (partially) on a regular basis. It really makes a huge difference
in years of service the battery is going to give in return. Especially winter
time is a battery killer. I leave the bike hooked to the charger via an old
fashioned timer device, and devide a 24 hour cycle into 4 sections,
each charging the battery for 3 hours at a time. In the " Off " time
the battery can rest and discharge slightly. Watch fluid levels!





Rescue team: Diesel engine glowplugs.



Every now and then I come along and give the battery a good scare with the
help of the device you see in the photograph. The homemade superduper
discharger. It consists of six diesel engine glowplugs in parallel, and
when I hook these up for a short time ( they become red hot ) the
battery has to let go for a lot of amps and a significant voltage
drop is the result and that's " Action " . When the bike is not
in use I perform this every other day or so and the battery
seems to like it very much indeed. The glow - up timing
becomes shorter as a result. It's like flexing muscles.



THINKING OF IT, ACTUALLY ...





This device is commercially available and also works by putting a load
on the battery, there is a glow coil behind the grid and the readout
is an old fashioned Volt meter. Can also be used for
checking the alternator of a running engine.

Warning: If you are going to get one, make sure the claws are
insulated on the outside ... and not bare like these ...






Continue to Exhaust Tone






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