Hello guys,

I started this topic after my bike runs reasonably well. SO I'd better close he topic " SUdden 'Death' ".

This morning I tried to start the bike again, but after 2 pushes on the stater button, the battery ran flat. Again I jumped started the bike..it ran pretty smooth. I checked the Volt at the flat battery terminals...12.8V. I turned ON the head light, the voltage was 12.2V. I believe the alternator is working well.

After about 10 minutes run, the fan was ON automatically....this is great. I wonder why the previous owner had the wire bypassed directly to the battery and manual switch????

Now I suspect my battery is faulty (?), because it does not keep the power even overnight. Any comment or advice please.

In the manual or standard, the bike uses 30Amps battery. If I use a 45 Amps battery, is this ok for the alternator / bike? Will this bigger Amps affect other electrical system or components?

Your comment, input and or advice are much appreciated.

Thanks & regards.

Additional information.

The present battery is Yuasa lead acid 24 Amps.

I am thinking of replacing it with 45 Amps sealed Calcium battery.

Thanks.

Adiwan Djohanli wrote:Additional information.

The present battery is Yuasa lead acid 24 Amps.

I am thinking of replacing it with 45 Amps sealed Calcium battery.

Thanks.

Be caredull to research the charging requirements for the cadmium battery you plan to replace. The charging circuit of the K-bike was not designed with a mind to the requirements of modern battery technologies. So, it is possible that the charging voltage/current profile supplied by the K-bike will not complement the battery you choose. It could prove to be an expensive replacement if the charging circuit on the bike destroys the battery. In the case of the K-bike, I would recommend sticking with lead-acid battery technology unless you have evidence that other technologies are compatible.

I'd measure first what's going on. It might be that the alternator is gone and hasn't got sufficient voltage/amps to charge the battery.

Put a volt meter on the bike and see what happens whilst you drive. I would expect to see about 14V as soon as you drive around 1500 rpm or higher. It could be that one of the diodes of the alternator is gone, which would result in limited charging and lower voltage.

Even a not so good battery should at least try to kick the engine over.

Unless something is sucking on the battery.....
Unplug the positive of the battery and put an ammeter in series . When the ignition switch is off, the only thing that should drain the battery is the clock.

Before you go to the huge expense of an enormous battery have a look at the batteries the current K-series and Japanese bikes are running.

As mentioned in another post the only requirement of the battery is to start the bike so a larger capacity seems overkill.
I realised there was no need to run a 30 or even 24 AH and am down to a 19AH AGM from eBay although I think it might be mislabeled and is probably only 14 and is more than adequate and is smaller and lighter as well.

Being AGM it can also be mounted in any direction except upside down.

Alternatively a bit of research on the new LiPo technology reveals that 5AH is more than sufficient and they are now commercially available starting at around $170 US

Hello Guys,

I checked the voltage at the battery terminals while the engine is running.

It reads 12.8V and when I turned ON the head light and cooling fan was ON, the reading was 12.2V. You mentioned 14V @ 1500 rpm or higher.

Is the lower voltage due to charging the flat battery?

I shall check the possibility of power drain with Amp meter and report back.

BY the way, the replacement battery in mind is SEALED CALCIUM maintenance free...NOT Cadmium.

Thanking you for all the input and advice.

Have a nice day and regards

Hi Adiwan,
As you will read elsewhere on this site there is little output from the alternator until you are running above 1500 and really above 2000 rpm for good output. Measuring at idle will not tell you much and in fact with the headlight on the battery is going flat at idle as the alternator output is not sufficient for the total load.

The battery our bikes was designed for is a normal flooded 30Ah lead acid battery not a lead calcium battery. Lead calcium batteries are not good when subject to deep cycling as a point of interest.

The K100 is effectively a car engine in size and no way would I consider a 14 or 19 Ah battery for a car even an under 1 litre car, 30 Ah is the recommended size. There are excellent Yuasa 30Ah flooded cell lead acid batteries available ex stock at lots of dealers.
Regards,
K-BIKE

The standard battery for the early models was 20AH, 30AH was for the "special" version which I believe related to the police models.

One would hope that battery technology has changed a tad since 1983 and while 30 A may have been ok then the fact that modern K1300 engines with much higher compression ratios or high compression 900+ twins start quite happily with 19 or 14 AH batteries.

In theory a 14AH battery will provide enough power to run the K100 starter continuously for 15 minutes and if it has not started by then I would suggest you have issues.

Why you would need to run it for twice that period is up to you. Perhaps if you were in the courier business maybe but then one would assume a more appropriate bike.

I took off the + battery terminal and checked the Amps, ignition key was OFF. It read 4.9 mA. I believe it is the clock. No power drain. Re-connected back the + terminal, checked the voltage 12V.

I tried to start the engine, but only turned slowly. Obviously not enough Amps for the starter motor. So I jumped started using a running car battery. The bike started reasonably well.

Then I took the bike for a ride around the area. I only turned ON small light, hoping the alternator should charge the weak battery. After around 20 minutes riding, cooling fan was automatically ON. Then the temperature meter slowly drop from above 2nd white line after the blue zone to near blue zone. It happened approx. 10 minutes of fan ON. But at the same time the overheat warning light (on the dash board) was ON.

The engine stopped accidentally (after approx 25 minutes riding). I restarted the bike, it was good and the engine ran..no problem. Meaning the weak battery was charged. However I will take the bike to a battery show to check the alternator charging capacity.

This is NOT right, temperature meter indicated near the blue zone. Cooling fan was still ON. I shall check the temperature sensor tomorrow.

I will update you the progress accordingly.

Best regards.

Adiwan Djohanli wrote:... Then I took the bike for a ride around the area. I only turned ON small light, hoping the alternator should charge the weak battery. After around 20 minutes riding, cooling fan was automatically ON. Then the temperature meter slowly drop from above 2nd white line after the blue zone to near blue zone. It happened approx. 10 minutes of fan ON. But at the same time the overheat warning light (on the dash board) was ON.
...
This is NOT right, temperature meter indicated near the blue zone. Cooling fan was still ON. I shall check the temperature sensor tomorrow.

I will update you the progress accordingly.

Best regards.

In the previous thread, "Sudden Death", you posted:

The cooling fan was ON after about 10 minutes of ride. Of course I had
re-wired back to its original electrical scheme and I installed a Toyota
thermostat - 76.5 C.

There are two thermo couplers that read water temperature. One is located on the drain port of the water pump and the other is located near the left side of the engine block. The first coupler is used to indicate water temperature for the water temperature gauge. The second coupler has two sensors built into it -- one for the ignition control and the other for the over temperature light on the instrument panel. Read these articles on Ktech:
Cold Running Problems
Fan System Diagnostics for 2V Kbikes

They may point to your problems. The over temp light coming on may indicate a bad connection to the sensor or the thermo couple on the water pump may be defective and you may possibly have cooling problems. I believe the 76.5 degree thermostat is too cold for the Kbike engine. It really should be 89 degree (for cooler climates) and 82 degrees (for warmer climates). Read this tutorial:
Installing a water temperature gauge
for information about the thermocouple properties and the correct temperature indications on the gauge.

Taking a guess here -- the thermo couple on the water pump may be
correct and the thermo couple on the engine block is problematic.

At the end of the day, and unless you are into fabrication of custom bits, the best battery to have is one that's of the appropriate spec and which fits into the intended tray. The factory mounting bracket incorporates the coolant reservoir and to leave this dangling can lead to misery down the track. I'm using Yuasa's excellent YMF sealed lead-acid 20 amp battery and with its accompanying plastic tray it fits the smaller of the two battery receptacles and uses the factory top mount which holds the coolant overflow bottle in place, no worries. The bike spins and starts first go every time with this one.

For the record most of the newer BMWs, including the new K13 series, use a 14 amp hour battery, albeit, with an often larger alternator output than our bikes due to the added electrical requirements of ABS and ancillary gizmos. Along with a myriad of cool things like heated seats and GPS, traction control, tyre pressure monitor and dash-mounted trip computer that you can toggle through like a Gameboy to pass the time, if you find yourself terribly bored and somewhat isolated from reality due to the extreme levels of rider comfort offered on long treks, have you heard about the optional radar-operated field mouse counter fitted to the upcoming K1600GTL?

Two Wheels Better wrote:have you heard about the optional radar-operated field mouse counter fitted to the upcoming K1600GTL?

What... The K1600GTL is equiped with a cat scan???




I am better to run....

That might be needed for the class of person who would buy such a large touring beast; well-off, post middle age crossover Goldwing riders and such...just saying! Or perhaps it's a heart monitor that's needed.

Gents,

Thanking you for the input. I understand there are lots of thing I must learn quickly in this regard.

I will read the topics of fan / cooling as advised.

Personally, I prefer a good music on the bike for long distance riding...

Have a nice day and regards.

Adiwan, can you check the coolingwater temperature separately? The gauge gets its signal from the pump, where a sensor is fitted in the drain hole. The fan/overheat light and the ECU get their signal from the sensor in the stubpiece on the left forward side of the engine, just behind the radiator. It is quite possible that the gauge indicated 'cool', but the fan and warning light come on. I have had the same issue and had to replace the temperature sensor for the fan/ECU. I found out that it was that sensor by measuring the temperature of the coolingwater pump cover with a temperature gun, but you could temporarily fit a normal thermometer as well. At the time the measured temperature corresponded with the gauge, so the bike was not overheating and the other sensor had to be faulty. All was well after replacement.

Hello Rene,

Thanks for the input.

Firstly I must do a total check on the battery and alternator to make sure they are in good working order. If not, I need to replace them. I have not done these yet due to my work load.

Then next, I shall check the cooling system, pump, fan, sensors.

Cheers.

Adiwan, don't despair, we'll get to the end of this! Good memories of your beautiful country BTW!!
Cheers, Rene

This advice recently comes from another K-bike forum and may apply to your case. I'll quote verbatim:

If a battery has been left in a totally flat or faulty state and somehow
you got the bike running say with a jump lead start, then 2 things can
happen.

The alternator electronic regulator can get fried (1) if the jump
starting isn't done right and (2) when the bike starts there is no
battery (if faulty) and the alternator can put out lots of volts.
Sometimes but not always, the alternator controller is designed to stop
this. I've had a perfectly good alternator which has fried its regulator
after a jump start, so I never do this on vehicles now.

Do what FlyingDuck says.

Check your wiring diagram. On most alternators there is usually a single
wire connector on the side of the alternator that drives the charge
light. You should measure the voltage there first, running and not
running before taking it apart.

The regulator you'd be looking for will be equivalent to this unit: Bosch Internal Voltage Regulator

Hello Guys,

Finally I decided to replace the Yuasa 24 AH (faulty) with a 45 AH Calcium battery, brand "Kobe" made in Korea.

It has been 3 days now. So far it works well, the bike starts on the first push of starter button...

As mentioned before, I had put back the bypass wiring of fan to its original scheme. The fan works well so far, red over heating light is ON from time to time, I assume this is due to the temperature ups and downs. Bearing in mind here the air temperature is around 35 C.

I am pleased with the outcome so far. For the 3 days I rode the bike for about one hour each night. It ran well.

My next "projects" on the bike is to continue monitoring the performance of the cooling system, speedometer and turning indicator's lights.

I shall make a new topic regarding the progress.

I am very grateful and thankful for all your comments, inputs and advices.

Have a nice week end.

Best regards.

See if you can borrow an IR remote reading temperature measuring tool and when the overheat light comes on next stop switch off and measure the temperature of the rad and that will give you an idea if it is actually overheating or if the warning system is malfunctioning. Check the rad is free of dust, dirt and squashed bugs which block airflow. Don't water blast from the front to the back though that will fill the fan motor with water and cause it to fail.
Regards,
K-BIKE

Hello K-BIKE,

It is a very good advice. Thanks a lot. I shall do it.

I shall make a new topic about the temperature / cooling system.

Cheers.