Question NC700X won't turn over...?

[spark82]

Long shot question: did you check the clearance of the exhaust valves? I know that it is not very probable, but one of the reasons for the resistance of the cylinder stroke would be that the exhaust valves would not open, e.g. due to a timing error (the chain could skip).
It is easy for me to come up with crazy theories when I am not seeing the patient.

It's not out of the question, I looked at an animation of the NC engine (I tried to visualize it in my head and failed ), when the right cylinder compresses, the left cylinder is in the exhaust stroke. If the exhaust valves are not open yet, it's probable that the starter cannot overcome the increased load. Which is not a factor if the spark plugs are out.
I'm still at work, I'll check when I get home.

 

[showkey]

Ocham's razor, also known as the principle of parsimony or the law of parsimony, is the problem-solving principle that "entities should not be multiplied beyond necessity", sometimes inaccurately paraphrased as "the simplest explanation is usually the best one."


The law of parsimony is a principle that says that the best explanation is the one that requires you to make the fewest possible assumptions about what’s involved. Another way to say this is that the correct explanation or solution is usually the simplest.


When applied to troubleshooting………something simple was missed, not tested or overlooked in the early stages.

 

[spark82]

Ocham's razor, also known as the principle of parsimony or the law of parsimony, is the problem-solving principle that "entities should not be multiplied beyond necessity", sometimes inaccurately paraphrased as "the simplest explanation is usually the best one."


The law of parsimony is a principle that says that the best explanation is the one that requires you to make the fewest possible assumptions about what’s involved. Another way to say this is that the correct explanation or solution is usually the simplest.


When applied to troubleshooting………something simple was missed, not tested or overlooked in the early stages.

I agree with you on this, but Occam is mostly against "impossible" theories, which are not easily tested. Timing chain issues are not that uncommon with the NC, and it's easy to check.
I checked it, camshaft seems to be where it should be, the marks align.
So still no solution, I'll keep thinking and trying.

 

[itsmenc700]

Sorry bigbird you must not live in a cold part of the country and need to jump a dead battery car.
Every time I do this the "good, donor" battery should be running so as to have the needed power to get the dead battery car started - no questions.
I havent read a manual to see if they do say something like that, but if they do they are not helping!

Secondly the hissing sound when the plugs are installed must be the compressed cylinder loosing its pressure when the exhaust opens.
I see nothing wrong hearing that sound.

 

[itsmenc700]

If it was a valve timing problem and the battery current could not over come the resistance from the compressed cylinder the battery voltage should show how hard it is working and the starter motor should also heat up with such stress. So reading the battery voltage while pressing the start button should show results of this.
This would then also show using a car battery, which I mentioned previously, that it has mush more current and current reserves and should be able to either over come the resistance and/or greatly heat up the starter motor!

 

[spark82]

We can say that you are right. There is also a starter clutch between the engine starter motor and the engine, but it can be concluded from the design of the clutch that this is not a problem.
So he must go back to retest the battery and connections to the engine starter motor.
This is somewhat frustrating as it should be resolved relatively easily.

(I checked the valve timing, see above. It's OK.)
Considering the bike ran fine the last time I used it, one would think the problem can be narrowed down to the battery, the leads connecting it to the starter motor and the wheels and the clutch between the starter and the main shaft. Not that many variables.
The main shaft moves "freely" (not considering compression etc.), the small wheels and their axles seem to be in order, the clutch works as supposed. Now I have two starter motors, not plausible that both have the same problem (and to the same degree, so both move, but not enough force), so there is the leads and the battery. I tried 3 batteries so far, and two different cable sets directly connected to the starter motor.

I think I'm gonna try again tomorrow from the start. Good thing I have more than one month until the season starts around here.

 

[spark82]

Sorry bigbird you must not live in a cold part of the country and need to jump a dead battery car.
Every time I do this the "good, donor" battery should be running so as to have the needed power to get the dead battery car started - no questions.
I havent read a manual to see if they do say something like that, but if they do they are not helping!

Secondly the hissing sound when the plugs are installed must be the compressed cylinder loosing its pressure when the exhaust opens.
I see nothing wrong hearing that sound.

With cars it's no problem as their regulators actually regulate the excitating current of their alternators. So if you connect another car to yours, your regulator will only set your alternator excitation current to zero if the voltage is above the set limit. If you try to jump a bike from a car, it's another thing. Bike regulators convert all the energy that is not needed to heat (as their alternator uses permanent magnets, not electromagnets). So if you connect a running car to a bike to jump it, the bike regulator tries to "regulate" the car voltage, as in converting all the excess energy to heat. And a car alternator is much stronger than that of a bike.
Smoke may come out of the bike regulator during that time...

Edit: if somehow the bike regulator voltage limit is above the car regulator limit, that may save the bike regulator, as the car regulator acts before the bike regulator gets the chance and fries itself. But I wouldn't rely on that.

 

[TheIronWarrior]

With cars it's no problem as their regulators actually regulate the excitating current of their alternators. So if you connect another car to yours, your regulator will only set your alternator excitation current to zero if the voltage is above the set limit. If you try to jump a bike from a car, it's another thing. Bike regulators convert all the energy that is not needed to heat (as their alternator uses permanent magnets, not electromagnets). So if you connect a running car to a bike to jump it, the bike regulator tries to "regulate" the car voltage, as in converting all the excess energy to heat. And a car alternator is much stronger than that of a bike.
Smoke may come out of the bike regulator during that time...

Edit: if somehow the bike regulator voltage limit is above the car regulator limit, that may save the bike regulator, as the car regulator acts before the bike regulator gets the chance and fries itself. But I wouldn't rely on that.

Looking at the service manual, a bit of Google, and some personal experience, it might be that the bike's regulated voltage is above that of the car battery.
The SM gives the max charging voltage as "<15.5V" at 5000 RPM.
Google tells me that bikes (broad generalization) are typically regulated to 14.6V
Google also says that cars (broad generalization) are regulated between 13.5V and 14.5V.
I've monitored the voltage in my car and I think I've only even seen values below 14.5V.

HOWEVER:
Knowing that a car electrical system is significantly larger that that of a motorcycle, and
Knowing that I do not have a comprehensive list of all car regulator voltages, and
Knowing that a faulty regulator can cause high voltages as well as low voltages, and
Knowing a car battery is generally significantly larger than a motorcycle battery,

I would NEVER use a running car to jump a bike. Unless the car battery is already on the way out or pretty deeply discharged, it should have more than enough juice to get the bike going and there's no risk of frying anything.
Using a running car introduces much more risk that I'd fry something on the bike and it would be almost always unnecessary for the car to be running to provide enough power to start a bike.

 

[lootzyan]

...So if you connect a running car to a bike to jump it, the bike regulator tries to "regulate" the car voltage, as in converting all the excess energy to heat. ...

In a motorcycle, the battery and alternator are permanently connected to each other. There is no disconnection in this circuit, just a fuse.
If, as you describe it, "the bike regulator tries to" regulate "the car voltage", the same way the regulator could try to regulate the bike battery voltage, right?
So why is the battery not discharged when the engine is not running and the alternator is not generating energy?
Because the current from the alternator can only flow in one direction, to the charging circuit.
It is no problem to use a car to jump start a motorcycle as long as the voltage does not exceed, say, 14.5 volts.

 

[itsmenc700]

You didnt state dont run the car IF your jumping a smaller engine/motorycycle!!!

Again can you / have you measured the voltage WHILE pressing the starer button?

 

[spark82]

In a motorcycle, the battery and alternator are permanently connected to each other. There is no disconnection in this circuit, just a fuse.
If, as you describe it, "the bike regulator tries to" regulate "the car voltage", the same way the regulator could try to regulate the bike battery voltage, right?
So why is the battery not discharged when the engine is not running and the alternator is not generating energy?
Because the current from the alternator can only flow in one direction, to the charging circuit.
It is no problem to use a car to jump start a motorcycle as long as the voltage does not exceed, say, 14.5 volts.

The battery voltage, when the car/bike doesn't run, is lower than the set voltage of the regulator... And the bike regulator (or the regulator circuitry) also includes the rectifier, of course. In a car, the rectifier diodes are usually inside/on the alternator.
Your last sentence would be correct if you said "as long as the voltage supplied by the car does not exceed the set voltage of the regulator in the bike you are jumping at the moment". And most of the time you cannot be sure that it doesn't.

 

[TheIronWarrior]

In a motorcycle, the battery and alternator are permanently connected to each other. There is no disconnection in this circuit, just a fuse.
If, as you describe it, "the bike regulator tries to" regulate "the car voltage", the same way the regulator could try to regulate the bike battery voltage, right?
So why is the battery not discharged when the engine is not running and the alternator is not generating energy?
Because the current from the alternator can only flow in one direction, to the charging circuit.
It is no problem to use a car to jump start a motorcycle as long as the voltage does not exceed, say, 14.5 volts.

The bigger risk is that if the car's regulated voltage is greater than the bike's regulated voltage, you are going to run more current through the bike's system (note, not the Alt/R/R, but the rest of the system, presumably the diodes in the rectifier can hold back the voltage).
Unless I was absolutely sure the car's regulated voltage was equal to or less than the bike's regulated voltage AND the car battery was depleted enough that it wouldn't start the bike, I'd leave the car off. Might only be a small risk of letting the smoke out, but why add any risk for no gain?
Also note that if the car battery was depleted enough to not start the bike, you're not likely to get the car started either...

 

[lootzyan]

The battery voltage, when the car/bike doesn't run, is lower than the set voltage of the regulator... And the bike regulator (or the regulator circuitry) also includes the rectifier, of course. In a car, the rectifier diodes are usually inside/on the alternator.
Your last sentence would be correct if you said "as long as the voltage supplied by the car does not exceed the set voltage of the regulator in the bike you are jumping at the moment". And most of the time you cannot be sure that it doesn't.

First, the regulator also acts as one-way current gate. You know that. This is also to prevent the battery from discharging.
I don't know what the voltage rating of the average regulator is, but I can bet it can withstand less than 15 volts applied without any problem. So if the flow of current to the regulator is effectively blocked, there is no possibility of damaging the regulator. It doesn't matter how "strong" the car alternator is. Its voltage is also regulated. We are not talking about cases where the car's alternator is faulty.

 

[spark82]

You didnt state dont run the car IF your jumping a smaller engine/motorycycle!!!

Again can you / have you measured the voltage WHILE pressing the starer button?

I stated that if you run the car while jumping a smaller engine/motorcycle, the regulator may be fried. I think it's clear enough.

I measured the voltage while starting and posted it a few days ago. If I remember correctly it was about 10.2 or 10.3V while pressing the button, and the same if the battery was directly connected to the starter. That means a 2.5V drop. CCA for my battery is 210 A. I couldn't find the wattage rating of the NC starter, but it's somewhere in the 500W range (mostly under). The current for that is about 40A. The voltage drop (while understanding that it's not linear) of the battery suggests that the amps flowing through the starter is in that range (I can only measure up to 20A at home, so no exact figures).
So the amps go to the starter and still it is not enough to turn the engine a full revolution, gets stuck on compression and then the compression pushes it back after I release the button/disconnect the cables. So it starts to turn the engine, it stops before being able to push it through the compression cycle but keeps it there and it stops. Then the engine turns back when I release the starter. The starter clutch works fine, as the engine won't turn the starter motor backwards.

Seriously considering giving up on electric started bikes and return to kickstarters.

 

[lootzyan]

The bigger risk is that if the car's regulated voltage is greater than the bike's regulated voltage, you are going to run more current through the bike's system (note, not the Alt/R/R, but the rest of the system, presumably the diodes in the rectifier can hold back the voltage).
Unless I was absolutely sure the car's regulated voltage was equal to or less than the bike's regulated voltage AND the car battery was depleted enough that it wouldn't start the bike, I'd leave the car off. Might only be a small risk of letting the smoke out, but why add any risk for no gain?
Also note that if the car battery was depleted enough to not start the bike, you're not likely to get the car started either...

If the door between us is closed no matter how terrible you are. If I can't see you, I'm not afraid of you.

 

[spark82]

First, the regulator also acts as one-way current gate. You know that. This is also to prevent the battery from discharging.
I don't know what the voltage rating of the average regulator is, but I can bet it can withstand less than 15 volts applied without any problem. So if the flow of current to the regulator is effectively blocked, there is no possibility of damaging the regulator. It doesn't matter how "strong" the car alternator is. Its voltage is also regulated. We are not talking about cases where the car's alternator is faulty.

Look, I'm an electrical engineer. I gave you my opinion to my best knowledge.
The bike has a 400W alternator, so let's say the bike's regulator is rated at 500W. Worst case is your regulator needs to dissipate the whole output of the alternator. That's 400W. Is it able to handle it? I suppose so.
You connect a car alternator to the system. Let's say about 1500W (Honda Accord to stay with Honda) Your bike starts up. You rev it up. Your bike regulator now has to regulate the output of its own alternator and a car alternator which has triple wattage. Your only line of defense is that bike regulators are generally tuned 0,1-0,2V higher than car alternators, but the values may overlap. And most likely you don't need to run your car to jump the bike, because the car battery will handle it anyway.
I'd choose not running the car while jumping the bike.

And one more thing. "The flow of the current to the regulator is blocked" is not correct. The flow of the current is blocked towards the alternator, it can (and does) flow to the regulator. And it can withstand 15V, but it expects that voltage to drop instantly, as it starts to regulate. If it doesn't the regulator becomes a smoke generator. Or a small brick. (Depending on the model.)

 

[spark82]

If the door between us is closed no matter how terrible you are. If I can't see you, I'm not afraid of you.

That's the problem. The door (aka the rectifier) is between the alternator and the regulator. Not between the battery and the regulator.

 

[lootzyan]

Look, I'm an electrical engineer. I gave you my opinion to my best knowledge.
The bike has a 400W alternator, so let's say the bike's regulator is rated at 500W. Worst case is your regulator needs to dissipate the whole output of the alternator. That's 400W. Is it able to handle it? I suppose so.
You connect a car alternator to the system. Let's say about 1500W (Honda Accord to stay with Honda) Your bike starts up. You rev it up. Your bike regulator now has to regulate the output of its own alternator and a car alternator which has triple wattage. Your only line of defense is that bike regulators are generally tuned 0,1-0,2V higher than car alternators, but the values may overlap. And most likely you don't need to run your car to jump the bike, because the car battery will handle it anyway.
I'd choose not running the car while jumping the bike.

And one more thing. "The flow of the current to the regulator is blocked" is not correct. The flow of the current is blocked towards the alternator, it can (and does) flow to the regulator. And it can withstand 15V, but it expects that voltage to drop instantly, as it starts to regulate. If it doesn't the regulator becomes a smoke generator. Or a small brick. (Depending on the model.)

I am not going to compete with you for the knowledge of the principles of electrical devices (even if I am an industrial electronics and mechanical engineer).
But you can try a simple test. With the ignition off, connect a simple ammeter in the charging circuit and see the value of the electric current. Somewhere in the Service Manual, Honda states what is permissible. Usually the value should be very small. Why is that if you say "" The flow of the current to the regulator is blocked "is not correct"? If the regulator is to regulate some voltage, the flow of the current must be ensured. But here we see "The Way Is Shut".
On the other hand, what would be the reason to connect a running car and a running motorcycle? Here we are discussing a jump start of a motorcycle with a weak battery.

 

[spark82]

I am not going to compete with you for the knowledge of the principles of electrical devices (even if I am an industrial electronics and mechanical engineer).
But you can try a simple test. With the ignition off, connect a simple ammeter in the charging circuit and see the value of the electric current. Somewhere in the Service Manual, Honda states what is permissible. Usually the value should be very small. Why is that if you say "" The flow of the current to the regulator is blocked "is not correct"? If the regulator is to regulate some voltage, the flow of the current must be ensured. But here we see "The Way Is Shut".
On the other hand, what would be the reason to connect a running car and a running motorcycle? Here we are discussing a jump start of a motorcycle with a weak battery.

View attachment 48149

I must apologize to you for one thing I overlooked, you were right: the regulator will not fry, the fuse will go first anyway.
I'm not even sure I fully understand your line of thinking in this last comment (it's already midnight here and I'm tired now).
The reason to connect a running car and a running bike? When you jump start, the moment the bike starts, both the car and the bike is running and they are electrically connected.

I'm not competing for anything by the way. I respect your opinion (for that matter, anyone's opinion), but we are going way off topic. And my bike still doesn't start. :/

 

[brb]

It appears all want to help but are just adding information that can apply. The Honda service manual has a troubleshooting guide in section 6. I myself have gone too far looking into a problem by overlooking the basics. Have you gone thru the factory steps? Other than that I always go over the ground circuits really good before getting too deep. They have been the problem too many times that I would like to forget.