[Gary856]

I thought a bit more and realized I missed something earlier, and this gadget just might work in principle.

As you already saw, you measured 0-19V as the light intensity changed. This is “open circuit” voltage that you measured with a dc meter, with no current flow. The analogy for “open circuit voltage” (i.e., no electrical current flow) is static pressure in a pipe, with no water flow.

Let’s say your battery is at 12.5V, and charging would occur when your charger’s output voltage rises above 12.5V. So:

– When the charger’s output voltage is at or below 12.5V, no current will flow, i.e., no charge. The charger just needs to have a diode (like a one-way valve for current) to prevent draining the battery, since the battery, being at a higher voltage than the charger, would attempt to force current back into the charger without the diode (one-way valve).

– When the charger’s output voltage start to rise above 12.5V, current starts to flow from the charger to the battery, i.e., charging. The more intense the light is, more current would flow from the charger to the battery, but the voltage would only go up gradually as the battery charges. Why? A charger is like an electrical pump. Think about an air pump analogy here. A small bicycle pump can pump up a skinny bike tire to over 100psi quickly. But, if you try to use it to pump up an air mattress, no matter how fast/hard you pump, the pressure will build up extremely slowly, since the there’s a lot of air volume to fill. On a solar charger, with very limited current producing capability, charging the battery is like using a bicycle pump to fill a mattress. It’ll slow charge/fill, and the voltage/pressure would only build up slowly.

I hope this makes some sense, since I struggled to put this into words. Please, no more electrical questions; let’s go back to talking bikes.

[Gary856]

I can’t make specific conclusions les I make a fool of myself. I did just look at their website and the limited product description, and I must say that I have doubts about this product. Not saying that I know it wouldn’t work; just saying I’m not convinced that it would.

You saw 0-19 V fluctuatin with a steady light source (i.e., sunlight)? Beats me why – doesn’t seem normal unless the sunlight intensity was changing accordingly during your measurement. You’re right, if its output is unregulated like that, how’s it supposed to charge a battery?

[Gary856]

Good article – myth busted!

The surface “grime” (acid, dirt, moisture, etc., on a battery case), being ever so slightly more conductive than a clean surface, could allow a tiny bit of current to flow between the + and the – terminals, thereby speeding up the self-discharge of the battery.

A storage battery on a trickle charger is a completed circuit – of course; the battery couldn’t be charged unless there is a compelted circuit. The charger takes energy from the ac wall outlet, converting ac to the suitable dc voltage and current, and “pushes” the charges into the battery. The dc side of the charger circuit (two leads, + and -) forms a complete loop with the battery.

[Gary856]

My DRZ recently died due to a weak battery DURING a night ride.

I hadn’t ridden it for almsot a month (due to travel and stuff). The bike started a bit hesitantly but then it ran fine. About three miles down the road, I got stuck at a traffic light for a couple of minutes, because the police had blocked off the road due to an accident. When I finally got clear, I made it to the next light, and as I slow down and signaled to turn, the bike died. It woudn’t restart, and the cranking got weaker quickly. My wife came by and gave me a jump from the car battery, and the bike started right up. I rode it home in heavy rain just fine. The bike sat for another 2 weeks, and yesterday I rode it to work and back home (39 miles total) ok.

I think what happened was I started with a weak battery (from sitting for nearly a month), didn’t go far, and then idling at the light, with the brake light on, drained the battery below the level to keep the bike running.

[Gary856]

Interesting trick on the lever’s lateral position, TrialsRider. I normally use two fingers to clutch/brake and I was thinking it was too bad that I couldn’t take full advantage of the leverage offered by the long levers since my index/middle fingers are closer to the lever pivot points. I could move my hands outward more (toward the bar-end weights) and achieve the same effect you’re showing (pulling on the levers farther out from the pivot), but that would result in longer reach for the levers, which makes lever control a bit harder, so it seems a wash. An adjustable-reach clutch lever would be nice.

Back to the angle thing. The clutch lever on one of my bikes is noticeably stiffer than my other bikes. When I first got the bike, I had to bend my left wrist up slightly, and I needed to use 4 fingers to control the clutch lever comfortably at low speed. After I angled down the clutch lever, now I can easily use 2 fingers again.

[Gary856]

I’m an EE, and circuit 101 says current, like water, cannot flow unless there is a closed loop/path. In a battery, there must be a path between the + and the – terminals for the current to flow, i.e., the battery to drain. One can connect the battery + terminal to earth/concrete floor, but if there is no path back to the – terminal, no current will flow, and no drain will occur.

However, current drain is not the only way the battery gets weak. Since batteries generate electricity from chemical reaction internally, temperature has a big affect on the chemistry, i.e., low temperature slows down chemical reaction significiantly. I’m guessing that the concrete floor, being colder and a better heat conductor than a bench top, could have the effect of chilling the battery more. I don’t know if that would cause permanent damage or not, but maybe it depends on how cold it gets where you are, ’cause I guess you wouldn’t want a wet-cell battery to freeze.

Now, the funny thing is, for dry-cell disposable batteries (AA, C, D, etc.), they say to keep them in refrigerators to keep them fresh longer, i.e., slows down the internal chemical reaction. You just need to let them warm up enough before use.

[Gary856]

Kirk, wouldn’t it be possible for you to run an extension cord to the backyard and hook up a battery tender that way? You don’t need to do that 24/7, but I’d try doing it maybe 1 full day per week when it’s not raining, and see how that works out in keeping the battery charged up. For safety you’d want to use an out-door rated cord plugged into a GFCI circuit.

[Gary856]

If you only let it idle for 10 minutes, with the headlight and taillight on, I don’t think you’d charge the battery much. You may even be draining the battery with a low engine speed and the lights on. I don’t know what rpm you need to be at for max charging current – that depends on each bike’s charging system – but I’d guess it needs to be 3k rpm or above. Even then, not sure if 10 min per week is enough, especially when it’s cold, besides the fact that running the engine but not going anywhere is a pretty inefficient way to charge the battery.

[Gary856]

You’ve identified the problems pretty well – cold, stored in the open, no battery tender, ran infrequently. When you do start the bike, do you run it long enough, at high enough rpm, for the battery to charge? It’s generally true that a fully drained battery would suffer some degree of permanent damage, but it seems yours was just low.

The only thing I can think of is to remove the battery from the bike and store the battery indoors. Even better if you could have the battery hooked up to a battery tender indoors.

[Gary856]

Read between the lines – the guy started by saying he gets to ride a lot of exotic/expensive bikes, so his liking the KLR650 is a bit like a food critic who eats fancy stuff at top-tier restaurants all the time saying at the end of the day he enjoys a good old hamburger the best. It’s impossible to pick one best bike so whatever one picks is simply the one that fits the mood at the time.

I used to think the KLR650 was too “soft” for my taste, that it doesn’t excel at anything. But the more I read about it, the more I think it’s one of those bikes that makes the owner happy by exceeding the expectations with it’s simple, low-cost, honest-to-god do-it-all capability. For the freeway I’d still prefer a sportbike, but for everywhere else I don’t see why I wouldn’t be very happy with a KLR650.

[Gary856]

I’ve worn a pair of Rev’it overpants since June ’09 about 6 days a week with no problem, but the only zipper that gets used daily is the fly. I almost never use the leg zippers since I put on/take off my boots (change to regular shoes) before the overpants. I only put in/take out the liner once a year as the seasons change. I can see lower quality zippers being the weak link if they’re used all the time.

[Gary856]

See if these tires are available for your sizes. These new generation sport-touring tires are high-performance all-season tires, and can last close to 10k miles for many people/bikes.

Perilli Angel ST
Michelin Pilot Road 2
Dunlop RoadSmart
Bridgestone BT023

[Gary856]

If all the controls function normally then it’s usually no big deal to ride it. After a low-side deep in the hills with a bent handlebar, levers, mirrors and busted gauges, I rode my bike maybe 30 miles home at a chilled pace, then to a shop. I’d get things promptly fixed, but there are people who ride with a slightly bent handlebar indefinitely.

[Gary856]

Of course, I’m way too old for this stuff, but the bike looks so freaking cool !!!

http://www.youtube.com/watch?v=BCGC_qh6dC8

[Gary856]

Ah, I didn’t watch the Tony Bou video until just now – that’s the kind of riding I thought trials was. Mind boggling! I’d declare it impossible to do if I hadn’t seen it. One problem I see with this kind of video, like watching MotoGP, is the top pros do it so smoothly they make it seems effortless. Then you have us mortals go out and play copycat, and that can result in very painful lessons. Don’t want to know what it feels like to fall 6 ft and land on the edge of an open concrete pipe!!!

Eon’s link was the one I saw earlier and thought looked more like a “regular” dirtbike competition.

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