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1990 K75 RT needs a new Battery

nickrides

Nick Kennedy
Could I please get some advice on a new Battery
Looking for good Value, don't really want to spend a ton here
I'm leaning towards a old school lead acid as they seem to last the longest.
Also my charging system is at 14.0 volts, is this enough volts? Can it be tweeked a bit higher?
Thanks
 
Check the Oilhead thread for batteries, there are spreadsheets...............

Lead Acid is great in my opinion and four years is a nice average. 14.0V is about max in my opinion. Most systems stick to about 13.8V. If you start messing with voltage, like in the Oilhead post, you get the results they are getting and just not worth the hassle.
 
hey dieselyoda could you get away with the lawnmower battery in the K. There should be room

I HAD an electric start lawn mower with a VRLA but guess where you put any lawnmower during the winter? That didn't win one of my better moves to brag about.

I'm just saying a lead acid, a good old flooded one needs a lost less care and fussing than some of the others. Read the Oilhead posts, I don't have the inclination to worry about a few milli-volt draw or tenths of a voltage charge to keep an extra $40.00 in battery cost alive. I like simple.

FYI, all the topics about GEL, VRLA and AGM have never been at consistent -40C temps. They freeze, break, open up and leak when warmed up in a shop. That's another topic, how to clean up the mess and save the machine and your clothes. I've tried them, all. A good lead acid is reliable, easy to maintain but, performance is a little weak compared to the others and if you get more than 4 years from one, that's some bragging rights.
 
My son got an Advance Auto parts battery for his K-bike, '87, and he loves it. Turns it over faster than ever.
 
I had been buying BMW batteries because they lasted 5 to 6 years, but they got really expensive ($165). Find a shop that sells Yuasa batteries and have them order one for your bike. I think it was about $90. Should be just as good as the BWM.

DO NOT BUY A CYCLE GEAR BRAND battery. I did once, it lasted 7 months. A waste of $70.:mad
 
Just a heads up on using a wet-cell tractor battery in a bike - most tractor batteries don't have a vent tube. That means the acidic vapors generated when the battery is charging exit up around where the caps (or sealing strip) are (is.) I have seen some rather severe corrosion in that area caused by those fumes. IMHO, not such a good thing when the engine ECU is sitting right above the battery. You do want a battery with a vent fitting on it you can attach a hose to.
 
Just a heads up on using a wet-cell tractor battery in a bike - most tractor batteries don't have a vent tube. That means the acidic vapors generated when the battery is charging exit up around where the caps (or sealing strip) are (is.) I have seen some rather severe corrosion in that area caused by those fumes. IMHO, not such a good thing when the engine ECU is sitting right above the battery. You do want a battery with a vent fitting on it you can attach a hose to.

It's a law in Manitoba, maybe all of Canada, unless you are using an AGM or GEL, you must have a vent tube that if the bike goes over, say in a crash, the battery can drain away from the bike onto the pavement.

I think this developed because the assumption was if the acid was out of the battery, the battery was effectively dead and posed no additional electrical hazard to rescue workers. If they assume otherwise, the battery is still live, they will split the bike in half to cut the battery cables.
 
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