I always like the idea of having a voltmeter on the dash, as it helps to understand what’s going on with the charging system on my bike… and it does, when it works fine! However, for whatever reason mine does not quite show the right voltage, always below by almost 1v.

Had to mention that, because it’s important, as batteries do like to be charged, but do not like to be discharged or overcharged! And that’s what happened to my battery.. obviously i did not pick that up straight away!

How it all started

One evening we were going back from the long ridout, and the bike started losing power. Voltage dropping to 9 volts and back up to 14 volts… I noticed that the bike still runs if the charging system gives 10v (or battery holds 10v I should say), but anything below that and it has no more power to run itself!

It started just by skipping a beat now and then, then intensified, stalling for a second… then for few.. and then completely losing it..

On the side of the road I checked the regulator rectifier, all wires seemed fine, so I thought it might be bad ground to the frame / engine or something, nothing I could do on the spot anyway! Somehow managed to get back home, as the day went and evening turned a bit colder, and for whatever reason problems disappeared too.. Now that’s where all the fun starts!

Back home checked the battery on the load tester for a few seconds, all seemed good. And since voltmeter (on the dash) never really showed above 14.4v i thought the rectifier should be fine too! Checked all the plugs again, cleaned the regulator rectifier plug as there was a sign of water getting in, and took it for a spin around the block… After 30 min riding my xt stalled again!

Stopped on the side of the road, took the seat and started checking everything while nothing was working and when I poked some wires it came back to life! So I thought – I must be wiring then!

**Picture:** *what a noodle party that was!*

Back home I took all the wiring loom apart, soldered all the connections, added a few extra ground points so I could attach them to the frame, one at the front, one half way, one at the back!

Went for a quick spin, and after another 30 minutes of riding it stalled and never came back to life.. sort of. The problem was that when I switched on the ignition, lights came on, fuel pump primed etc.. but when I pressed on the starter button – “click” and everything went dark. Over and over again!

After pushing the bike home for ~2 miles, and a quick debate with myself, I came to the conclusion that it must be a dodgy starter relay! Right? Wrong… swapping that didn’t help at all, same symptoms, same problems.

Back to square one!

Though I will start everything all over again, see what I have missed.. pulled the battery out again, plugged in the load tester again, and roughly after 20 seconds on it, voltage just dropped from 12 volts to 0! Checked again, with no load – over 12Volts, under load 0v. Now that was a surprise as the battery itself was less than 1 year old!

What caused the battery to behave like that?

Well when batteries get overcharged, all the excess heat tends to bow the metal plates inside of them, and because the distance between the plates is so tiny – they can touch, and then they do – lose all (or some) power as it basically shorts itself out. In some cases that movement inside can damage / crack connections to the terminals, and while the battery is still nice and warm it has no connection to its own terminals till it cools back down again, and I believe that’s what happened to my battery! Would explain a lot…

So back to the charging system, and this time with a normal multimeter, started the bike, and obviously the regulator rectifier pumps out over 15v! So it slowly cooked the battery for me, while my cheap voltmeter lied straight in my face all the time, nice!