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When is a Battery at Full Charge?????

I'm not understanding how a bike with a fully charged (and load tested) battery won't start using the starter motor, but will fire up by bump starting.
Some Information on this Subject.

A fully charged, Flooded Lead Acid Battery, is considered fully charged at 12.6 VDC.

An fully charged, AGM (Absorbed Glass Mat) Lead Acid Battery, is considered fully charged at 12.6 to 12.9 VDC, depending on the manufacture.

When starting the engine. The battery voltage is at, lets say 12.6 VDC. After the starter starts to rotate the engine. The battery voltage will drop to between 11 and 12 VDC. This is a normal voltage drop, considering the high amperage draw of the starter.

For the Ignition Coil to operate properly. The Battery Voltage at the Ignition Coil has to be 10.6 VDC or Higher.

If the Battery is Weak, below full charge status. The starter will still rotate the engine, to what the operator thinks is a fully charged battery. But the battery voltage at the Ignition Coil is below 10.6 VDC.

The engine doesn't start. So the operator, tries starting the engine again, so forth & so on.

So the operator tries a Push Start. The Push Start is a success, so the cbr and the rider is off on another Adventure.

So What is the Difference ?

The Difference is the Voltage at the Ignition Coil.

Even thou the battery was Weak. By Push Starting the cbr, instead of using the starter, the battery voltage didn't drop below 10.6 VDC, at the Ignition Coil.

Maybe it's Time to Think about getting a DVM (Digital Volt Meter) ?????
.
 

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Some Information on this Subject.

A fully charged, Flooded Lead Acid Battery, is considered fully charged at 12.6 VDC.

An fully charged, AGM (Absorbed Glass Mat) Lead Acid Battery, is considered fully charged at 12.6 to 12.9 VDC, depending on the manufacture.

When starting the engine. The battery voltage is at, lets say 12.6 VDC. After the starter starts to rotate the engine. The battery voltage will drop to between 11 and 12 VDC. This is a normal voltage drop, considering the high amperage draw of the starter.

For the Ignition Coil to operate properly. The Battery Voltage at the Ignition Coil has to be 10.6 VDC or Higher.

If the Battery is Weak, below full charge status. The starter will still rotate the engine, to what the operator thinks is a fully charged battery. But the battery voltage at the Ignition Coil is below 10.6 VDC.

The engine doesn't start. So the operator, tries starting the engine again, so forth & so on.

So the operator tries a Push Start. The Push Start is a success, so the cbr and the rider is off on another Adventure.

So What is the Difference ?

The Difference is the Voltage at the Ignition Coil.

Even thou the battery was Weak. By Push Starting the cbr, instead of using the starter, the battery voltage didn't drop below 10.6 VDC, at the Ignition Coil.

Maybe it's Time to Think about getting a DVM (Digital Volt Meter) ?????
.
Yes, I understand all that, but we weren't talking about a weak or partially charged battery, but rather a battery that is claimed to be fully charged and yet unable to start the bike via the starter motor. To me, this failure to start on a supposedly fully charged battery would indicate some other issue with the bike.
 

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State of Charge.

Yes, I understand all that, but we weren't talking about a weak or partially charged battery, but rather a battery that is claimed to be fully charged and yet unable to start the bike via the starter motor. To me, this failure to start on a supposedly fully charged battery would indicate some other issue with the bike.
From Giko's video's. From the sound of the engine, as Giko is trying to start it. To me, the battery is weak. In the first video. The engine would start a few times, but would not achieve an idle condition. What is keeping the engine from achieving an idle. Loss of minimum voltage to the ignition coil.

In the second video. Engine would not even try to start. I could hear the engine slow down as Giko was trying to start it. From a Battery that was getting weaker.

This is supposed to be a fully charged Battery. Check, Charged and Load Tested by a Honda Dealership. I Think I would get a Second Opinion of the state of Charge in the Battery.
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Discussion Starter #25 (Edited)
Before I did the video I did try to start the bike few times...so this may explain why the 2nd try was a little week...
Just to prove if my charger was working fine, ran the battery until it discharged. I am sure of that because the front display dimmed out as I was holding the start button. I had the battery connected to the charger for 6 hours and now it fully cranks the engine.

Remember that I am getting a good spark and I even tried using the quick start fluid, which we know works. Because the engine is rotating well, I don't believe the battery is the issue. Anyways I did as Wynne suggested just so you all can see.
Here is the video of the bike connected to my truck:

CBR250R 2 - YouTube

It does sound better but still it did not start.
More info: I tried quick start fluid as well with the battery connected to the truck, no start

@shisoshin - I did as suggested and no luck
 

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@ Giko,

Do you have a Multi-Meter ?
 

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@ Giko,

Being this is a computer controlled engine. The ground circuit is most critical. .2 volts can cause havoc with normal operations.

We start by checking the ground circuit. Meter on the 2VDC scale. Positive lead on one of the ground wire terminals at the voltage regulator. Negative lead to battery negative terminal.

Try to start the engine and see what is indicated on the meter.

What Model of Fluke do you use? I've used a Fluke 87 since mid 80's.
 

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Discussion Starter #29
@Soul Searcher
I'm sorry for the delay. I just came back from work and did the test.
I used a Fluke115 and I set it to MIN/MAX setting. Wires as you requested.
Min - 0.000V
Avg - 0.032V
Max - 0.345V
So for the split second there is a voltage drop of 0.3V, but on average it's only 0.032V. This voltages are while cranking the engine.
Is this what you were looking for?
 

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@ Giko,

I was hoping for a cleaner ground. But I have a quick cure for that.

We are going to bypass the frame ground, and go the direct route.

Using 14 ga wire. From the ground bolt on the voltage regulator to battery negative terminal. Use ring terminals on each end of the wire.

Remove the bolt at the voltage regulator that contains the ground wires. Add one end of the external ground wire to the bolt and reinstall.

Attach the other end of the external ground wire to battery negative cable retaining screw.

Try and see if the engine will start.
 

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Discussion Starter #31
update...
I did a compression test today and i got 75PSI.
I believe that this test confirms an engine rebuild... however IMO I should shill be able to start it with the ether. I have a good spark outside of the chamber, I have 75PSI compression so the ether should be enough to start it AND run the engine...,...and it's not starting,
WHAT AM i MISSING????

@soul searcher - I ran the 14ga copper wire, no difference...
 

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That's very low compression, particularly for an engine with only 10,000 km. The Service Manual lists compression as 188 PSI @ 490 RPM.

Did it previously have a Valve Clearance Inspection after the first 1000 km?... what were the results of that VCI?

I'd be curious to know what the valve clearances are now.
 

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Discussion Starter #33 (Edited)
I bought the bike at @1000km and I did the valve inspeciton myself at about 2000km.
Here is my post of the inspection:
Post #10
http://www.cbr250.net/forum/cbr250-service-maintenance/6078-cbr250r-valve-adjustment-diy.html
The clearance was:
Intake; 0.15mm
Exhaust: 0.25mm
all with in specs at the time. I'm renovating my house now so I don't have allot of time, but I will dedicate one evening for the valve check as I am interested myself.
Keep in mind few days after the inspection my water pump failed and I lost all the coolant, causing an thermal shutdown of the engine. All this happened within one hour of riding...After that I was able to run the bike for few thousand KM and the only problem I had was that the engine would die on idle. It would start up no problem...with a bit of throttle...
Here is the thread I started about that experience;
http://www.cbr250.net/forum/cbr250-problems-issues/12682-engine-overheated-now-stalls-randomly.html

What are you thoughts Mike? Should I be able to run it with ether, spark and 75PSI or pressure?
 

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Dont think 75 is enough. Had the same with a bike I restored. 70 pressure and would not start even though gas and spark were perfect. Pressure fixed and I started. And that bike was a 61 that only needed 120psi.
So when mike and the manual are saying 180, you wont go anywhere with 75
 

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... What are you thoughts Mike? Should I be able to run it with ether, spark and 75PSI or pressure?
Well, I'm thinking that if (a big if) it was able to start, with only 75 PSI compression it would run like crap, with a very noticeable lack of power. I don't think the ether makes any difference... with low compression being the apparent issue, the chances of it starting at all are pretty slim.

You stated in the opening post that it was recently running pretty well, and that the overheating shutdown happened roughly 7000 km ago. That's a little puzzling, but I'm not coming up with any other ideas off the top of my head, other than rechecking the valve clearances at this point.
 

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Discussion Starter #36
@saftie
How difficult was the restoration? Is it something you did for the first time?
 

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Discussion Starter #37
@motomike
As soon as I have an evening free, I will do the valve check and let you know...
 

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Valves or rings. Either way the head will have to come off mate :(

Keep us posted on your progress & best of luck.
 

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@motomike
As soon as I have an evening free, I will do the valve check and let you know...

When you were able to get it to run, was there blue smoke at all? If so then it probably has some serious piston ring problem. If not and the end of the exhaust pipe is not oily then my money is on a damaged or misadjusted exhaust valve.

I remember that an engine with about 7 or 8 to 1 compression ratio was coming up with 150psi compression. 130psi was OK and 110 was something wrong. You squirted engine oil into the cylinder and then redid the test. If the pressure went up substantially, you had a ring problem. If it stayed the same, you had a valve problem. Might be worth the effort to try.

Let us know what you find.
 

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Low Compression.

I did a compression test today and i got 75PSI.
When you did the compression check. Did you have the throttle at the Wide Open Position and crank the engine for 5 cycles (the gauge needle moves 5 times?

If possible, repeat the compression test after adding 2 to 3 teaspoons of engine oil to the combustion chamber thru the spark plug hole,

If the rings aren't seating properly, the compression should raise to 100 to 130 psi.

If the compression is greater than 100 psi. Reinstall the spark plug and see if the engine will start.

If the engine does start. Something to think about. For temporary operation of the engine. Mix some Two Stroke oil at 40 : 1 Ratio. 3.2 oz (95mL) oil to 1 gal (3.8L) of gasoline. This will aid in the Low Compression in the Cylinder.
 
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