Charging System QUICK TEST

[NOXUZ]

I appreciate your input. I was sure I had 12 volts on grounds, but double checked everything. Battery was hooked up correctly and 12.16volts on the grounds when the key is on. Since I discovered this issue, nothing happens when I hit start button. So I can’t test stator. My r/r has a white plug with I think 4 wires and a red wire with a bullet connection. When I disconnect the white plug or the red wire of the r/r, it kills the voltage to the grounds.

[posplayr]

I appreciate your input. I was sure I had 12 volts on grounds, but double checked everything. Battery was hooked up correctly and 12.16volts on the grounds when the key is on. Since I discovered this issue, nothing happens when I hit start button. So I can’t test stator. My r/r has a white plug with I think 4 wires and a red wire with a bullet connection. When I disconnect the white plug or the red wire of the r/r, it kills the voltage to the grounds.

I would strongly suspect your R/R. Remove or disconnect it completely. Try and start the bike. See why it will not crank over when you hit the starter.

[NOXUZ]

I’ll have to investigate more tomorrow. I tried disconnecting it but it also killed the dash lights and nothing happened when I hit the starter

[posplayr]

I’ll have to investigate more tomorrow. I tried disconnecting it but it also killed the dash lights and nothing happened when I hit the starter

Sounds like someone rewired the bike. Removing the R/R should not remove the battery from the circuit. The battery and R/R are in parallel to supply power to the electical system through the ignition switch.

[Mysuzyq]

Quick question, somewhat related. Is it normal for those r/r connectors to get hot whilst running? I attempted to do the quick test. Noticed the bolt on the battery negative terminal was a bit loose, which has happened before, probably due to vibration. I snugged it up and proceeded to take a few readings. Didn't get very far, as the battery is likely toast. After overnight charging on the tender, it showed 13.2v with key off, when I checked the terminals and noticed the loose negative bolt. Left it with the key on for about 40 secs (headlight on), then fired up the bike, fiddling with the idle speed for a few seconds to get it to idle. Whilst getting the meter probes into position on the battery, the r/r wire connectors happened to be in contact with my wrist, and I noticed them steadily getting hotter. I immediately shut off the bike....left it with the key and headlight on for about 20 more seconds while inspecting the wires. Bike won't crank now, shows 12.2 volt. Going to buy a new battery and then test. How warm do those bullet connectors normally get whilst running?

Edit: It is a later model r/r, fitted about 10 years ago. From a cbr, IIRC.

[posplayr]

Quick question, somewhat related. Is it normal for those r/r connectors to get hot whilst running? I attempted to do the quick test. Noticed the bolt on the battery negative terminal was a bit loose, which has happened before, probably due to vibration. I snugged it up and proceeded to take a few readings. Didn't get very far, as the battery is likely toast. After overnight charging on the tender, it showed 13.2v with key off, when I checked the terminals and noticed the loose negative bolt. Left it with the key on for about 40 secs (headlight on), then fired up the bike, fiddling with the idle speed for a few seconds to get it to idle. Whilst getting the meter probes into position on the battery, the r/r wire connectors happened to be in contact with my wrist, and I noticed them steadily getting hotter. I immediately shut off the bike....left it with the key and headlight on for about 20 more seconds while inspecting the wires. Bike won't crank now, shows 12.2 volt. Going to buy a new battery and then test. How warm do those bullet connectors normally get whilst running?

Hot means poor connection. There is no exception, regardless if it is something loose, dirty, corroded, or otherwise compromised.

The simple reason is that a larger resistance will dissipate more heat. So unless you are talking about much larger wires or connections (that can dissipate much more heat without getting as hot).

[Mysuzyq]

Thanks for the quick reply. Are you saying they should ideally run cool to the touch, when properly connected? Would testing with a shot battery cause them to heat up more than usual? Sorry if these questions are stupid; I'm quite a duffer when it comes to electrical problems.

[posplayr]

When you put a current path (e.g. a wire connecting a load) to the battery, current flows through that current path (cp). The current though the CP is the same no matter where you measure the current (think of water running through a hose where hose is cp and water is current). I'm describing a single current path with no splits or parallel paths.

Because the current actually goes in a full circuit (through battery, through cp and back through battery ...etc round and round), the amount of current flowing is determined by the total resistance in the battery plus cp. If that resistance is distributed evenly (ignoring battery connections) then the (cp) wire heats uniformly. However, if the resistance is concentrated at "connections", then those dissipate the heat in proportion to their total resistance.

If the bike's motor makes the wires warm, then the wires wont be cool. You just do not want a situation where the contacts are much (more than 10-20 degF) warmer than the rest of the wire.

If the battery is dead (low State of Charge), then there will be less current and correspondingly less heat all around independent of how the resistance is distributed, but still distributed in proportion to those resistances.

[Mysuzyq]

Thanks very much Posplayr, appreciate the simple explanation! I've never really had any electrical or even mechanical issues with this bike. Upgraded the stock r/r proactively, and have only replaced the battery every few years. It's very possible the connections now need attention. Thanks again!

[posplayr]

Thanks very much Posplayr, appreciate the simple explanation! I've never really had any electrical or even mechanical issues with this bike. Upgraded the stock r/r proactively, and have only replaced the battery every few years. It's very possible the connections now need attention. Thanks again!

Ohms law is V=IR

Relating that to the pictured analogy, the voltage push (or pressure) required to overcome a given ohm resistance is in proportion to the amount of current in amp (flow) you want.

For a given R ohms, Current increases with voltage.

All of these forms are the same law; if you know the value any two, you can solve for the third.

V=I*R
I=V/R
R=V/I



In the case of your low battery

I=V/R (assume R is constant)
A lower V gives a lower I.

What does that have to do with heat? heat is the accumulation of energy converted to heat. Like if you burn a wooden stick, the energy in the stick turns to heat, current pushed through R gives off heat in a similar way. In fact this is considered an ideal conversion of energy to heat.

Electrical power is given by P = I*V (in words the voltage times the current is electrical power). Substitution for i or V we get two different forms

P = IV=I^2*R = V^2/R

In P=I^2*R we see power is proportional to resistance R for any given I^2.

[Mysuzyq]

Ohms law is V=IR

Relating that to the pictured analogy, the voltage push (or pressure) required to overcome a given ohm resistance is in proportion to the amount of current in amp (flow) you want.

For a given R ohms, Current increases with voltage.

All of these forms are the same law; if you know the value any two, you can solve for the third.

V=I*R
I=V/R
R=V/I



In the case of your low battery

I=V/R (assume R is constant)
A lower V gives a lower I.

What does that have to do with heat? heat is the accumulation of energy converted to heat. Like if you burn a wooden stick, the energy in the stick turns to heat, current pushed through R gives off heat in a similar way. In fact this is considered an ideal conversion of energy to heat.

Electrical power is given by P = I*V (in words the voltage times the current is electrical power). Substitution for i or V we get two different forms

P = IV=I^2*R = V^2/R

In P=I^2*R we see power is proportional to resistance R for any given I^2.

Thanks for taking the time! I went outside and found the battery fully charged by the tender, so proceeded to do the quick test. The loose negative battery connection was probably causing the no-start situation I experienced after a 50 mile ride yesterday. The battery is about 3 years old (Yuasa), so I'll replace it regardless. Here are some numbers..
Key Off = 13.15
Key On = 12.33
Idle =12.66
2500 rpm (approx) = 12.80
5000 rpm (approx) = 12.89
Key Off =12.89.

Paid attention to the r/r bullet connectors... the wires do get hotter on the side after the connectors (away from r/r), but not super hot where they cannot be handled etc. The connectors certainly need to be refreshed.

Edit: Took another reading about 15 mins after shut down (no battery tender applied) and battery reads 12.66.

[posplayr]

Your stator is outputting pitifully but none of it is getting to the battery.
check your stator. Leg to leg and leg to ground test in phase b of stator pages.
if you fail that it is probably s burned stator because of s shunt r/r; join the stator pages aware club.

[Mysuzyq]

Okay, will do, thanks. Think I have a new stator in storage somewhere, bought about 15 years ago!
A friend was supposed to buy this bike last month, to export to Europe. Didn't go through due to the Covid travel situation. I'm glad he did not buy it, only to immediately have problems.

[Forden]

Here are my numbers. Looks like pretty weak charging, though at least it does increase a bit with rpm's--if anyone still watches this thread, thoughts appreciated. I've perused the stator papers (still in process of *understanding* them, haha) and want to be proactive about this now that I've finished some other work on the bike. I plan to install a new series R/R at some point in the not too distant future, wanting to assess the condition of the stator before then too.

Key Off = 12.51
Key On = 12.05
Idle =12.48
2500 rpm (approx) = 12.80
5000 rpm (approx) = 13.12
Key Off =12.68

Cheers.
Mike

[Baatfam]

Yah, those numbers aren't very good. Almost the same as mine when I replaced the regulator last winter...
Make sure you check your stator before you proceed too far. Mine was OK, just replaced the R/R with the SH-775 set up.
Afterwards I was getting 14.2 at 2500, and 14.5 at 5000.