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Tech Corner

Technical Q and A for classic motorcycle maintenance and repair.


Motorcycle Battery Worries

Motorcycle Classics tech expert Keith Fellenstein

Editor’s note: If you’re having trouble with that old Suzuki, BSA or BMW, Keith Fellenstein is your guy. From motorcycle tuning tips to detailed motorcycle engine repair, he can draw from a wealth of experience to help guide you to success. Send questions to: Keith’s Garage, Motorcycle Classics, 1503 SW 42nd St., Topeka, KS 66609, or send an e-mail with “Keith’s Garage” as the subject.

Battery worries

Q: I just went out to start my bike, turned the key and got no lights at all. I attached a battery charger and my USB port LED lights up, but I’ve still got nothing else lit. What should I check for? — Bob Gent/via email

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A: The first thing I’d check would be the charge level of the battery. Anything less than 12 volts and you definitely need to charge it. Next, I’d check the electrolyte level of the cells. If the electrolyte level is low or has been boiled off due to overcharging, the battery may show 12 volts, but have very little ability to push current, and current is what you need to make the incandescent bulbs in your bike light up. Your LED lights up because it requires milliamps of current where your incandescent bulbs require more. If you do find the electrolyte levels are low, go ahead and charge the battery. After it’s charged, add distilled water to each cell to bring them back to acceptable levels. If you do all this and still get no lights, have a look at the fuse box. MC