Voltage Problems, Plug Contacts, and General Charging Theory

[V7Goose]

This information will seem like old hat to those of us who have been around these bikes a while, but what I will explain below is that knowing and understanding something it is NOT the same as grokking it! This may be a little long, but I'll do my best to keep it concise. If you have noticed voltage fluctuations on your bike, this thread's for you.

 

The problem: For at least the last 20,000 miles I have had intermittent periods of low voltage on my 05, but only when running extra load like passing lamps. Occasionally the voltage while riding would drop down below 12, and at idle even below 11. But if I turned off the driving lamps it would jump all the way back to 13.8 - 14. I also noticed that when the voltage was low, often just a sudden increase in load such as a quick touch of the air horn or just flashing the high beams would cause the voltage readings to go back to normal. I have NOT had any problem with dead battery.

 

Although my bike is close to 100,000 miles and has the original six year old battery in it, I also noticed this identical problem on the 07 I had for a few months. This was a clue that I ignored.

 

Analysis: These are absolute classic symptoms for bad wire connections or pin contacts in plugs. Since the voltage was only low when the load was high, it indicated that excess current was being sucked from the battery instead of being supplied by the bike's charging system. The fact that it was not always low under those conditions proved that the charging system did have the full capacity, but it was not always being delivered to the battery. On the Royal Stars, the plug connecting the regulator/rectifier is a know problem with the pins for the main 12V and ground wires often overheating and melting the plug. The excess heat that melts the plug is caused by poor pin contact that works like a resistor.

 

Long ago I pulled this plug and it looked perfect. I also pulled the plug for the three stator wires, and all looked good there too. Over the past year or two I have periodically checked just about all plugs and wires, including grounds and battery cables without finding any problems. This problem can also be caused by an old or defective battery that just sucks up too much charging current, so this knowledge coupled with the fact that I still have the original six year old battery in the bike made me assume that had to be the cause. I never did see an excess charge current flowing into the battery on the ammeter, but just assumed that was because the only ammeters that are available these days have a + - 60A swing, and that is just too much to accurately see current flow on a 30A max motorcycle. I was just waiting for the bike to show some slow cranking to buy a new battery and prove the point.

 

The problem has been getting noticeably worse in the past few months. Still not having charging problems, but probably because I have been mostly leaving the driving and passing lights off. If I did not have full gauges and monitor them regularly, I probably would never even have a hint that there was a problem at all. If the battery had died two years ago, I would have just assumed it was normal old age for a motorcycle battery.

Surprise easy fix: Well today I decided to pull the regulator/rectifier one more time to check that plug. It still looked perfect. Although this circuit seems to be designed on the absolute minimum of what is needed for the 30A current, the plug does have a very good rubber seal in it that keeps out the crud if the plug is properly seated, and even after close to 100,000 miles, mine still looked like new. But still, I took the time to plug/un-plug the thing about 10 times to scrape the pins good, then I took a pair of needle nose pliers to slightly tweak the pins for the big red and black wires - the idea here was to make them press harder on the fittings in the plug and guarantee good contact.

 

Well guess what? When I took it out for several hours, even with fairly low battery voltage to begin with from sitting for several weeks, the system voltage NEVER DROPPED EVEN ONE TIME! This was an obvious fix that I should have done a couple of years ago, but the fact that my plug never showed any signs of heat problems fooled me into believing there must not be any problem with the pin contact there. WRONG.

 

The moral here is that even when things look right, they may not be. Never hurts to go the extra distance to clean/re-seat/tighten something that you suspected in the first place. It sure won't make things worse, and it just might fix it!

Goose

Edited October 2, 2010 by V7Goose

[Yeah, Just Dale]

Think a bit on that on the contacts would have helped things?

[V7Goose]

Think a bit on that on the contacts would have helped things?

No

 

I assume you are asking if using Dielectric grease on the plug would have helped. I do not think so. In fact, I am a bit surprised that just checking the plug in the first place didn't solve the issue. Simply pulling a plug off and putting it back causes the pins to scrape the surface and improve the contact. Dielectric grease does nothing to help the contact, it only helps prevent future corrosion from creeping between the pin surfaces and causing problems then.

 

It is possible that the problem got better for a while after I checked that plug the first time, but I did not notice that. If it did, then there is a possiblility that using DE grease at that time would have prevented it from coming back.

Goose

[MikeWa]

Thanks Goose.

 

Mike

[Seaking]

Very good info! Thanks again for sharing..

[Guest PlaneCrazy]

There's just one thing that I thought I should mention since it's something most people think but it's wrong... The battery supplies ALL loads for the motorcycle. The charging system is just that... it recharges the battery. In normal conditions, the bike uses up less current then the charging system delivers, so the battery stays fully charged or recharges after a start, etc. But, irregardless, whenever there is a need for power, it comes from the battery first.. not the charging system. Not only is the battery able to deliver massive amounts of current when needed (starting) but it absorbs all the shocks to the electrical system as loads are turned on and off.

 

In fact, on some cars, disconnecting the battery while the car is running will make it die. Depends on the capacity of the charging system and the way it is designed. never done it on a newer motorcycle though. In any case though... take the battery out of the system and you risk blowing up a lot of electrical components without the battery there to absorb the shocks.

[dingy]

There's just one thing that I thought I should mention since it's something most people think but it's wrong... The battery supplies ALL loads for the motorcycle. The charging system is just that... it recharges the battery. In normal conditions, the bike uses up less current then the charging system delivers, so the battery stays fully charged or recharges after a start, etc. But, irregardless, whenever there is a need for power, it comes from the battery first.. not the charging system. Not only is the battery able to deliver massive amounts of current when needed (starting) but it absorbs all the shocks to the electrical system as loads are turned on and off.

 

In fact, on some cars, disconnecting the battery while the car is running will make it die. Depends on the capacity of the charging system and the way it is designed. never done it on a newer motorcycle though. In any case though... take the battery out of the system and you risk blowing up a lot of electrical components without the battery there to absorb the shocks.

 

 

Not that what you are saying is wrong, but it is like which came first, the chicken or the egg.

 

A battery charged to maximum potential will on its own supply the requirements of the electrical loads. But once the battery voltage drops to a level where the voltage regulator is no longer shunting the excess current to ground, the circuit does not care where the electron flow comes from to supply its load requirements. The battery does flatten out the wave form that is coming from the voltage regulator, but this theoretically would happen any where in the electrical system. The voltage/current does not go into the battery as a rectified waveform, then leave again to supply power to circuits as a pure DC waveform.

 

Also, disconnecting the battery while a vehicle is running allows the possibility of the charging system producing to much voltage and blowing out electrical components.

 

The battery acts as a buffer to keep the charging system voltage at roughly 13.5 V.

 

Gary

[V7Goose]

There's just one thing that I thought I should mention since it's something most people think but it's wrong... The battery supplies ALL loads for the motorcycle. The charging system is just that... it recharges the battery. In normal conditions, the bike uses up less current then the charging system delivers, so the battery stays fully charged or recharges after a start, etc. But, irregardless, whenever there is a need for power, it comes from the battery first.. not the charging system. Not only is the battery able to deliver massive amounts of current when needed (starting) but it absorbs all the shocks to the electrical system as loads are turned on and off.

I am sorry, but you are wrong. In fact, what you describe is not even electrically possible, since the charging input wire must connect to the same post on the battery to which the bike load connects. Here are the facts about electricity:

 

Voltage is the force that pushes the electrons through the wire; you can think of it like water pressure. Current is the actual flow of the electrons - how much flows is a factor of the pressure behind it and the resistance in front of it; this is similar to the water in a hose. The amount of water that comes out of a hose is controlled by BOTH the amount of pressure behind the water and the size of the opening at the end of the hose. If you connect a hose to two different pumps, the one with the highest pressure will push water through the hose and into the other pump, despite the fact that the lower-pressure pump is still trying to push water at the same time.

 

The electrical system on a vehicle is essentially the same, with the battery and the charging system both being pumps, and the vehicle load connected between them. The pump pressure of the battery can never be more than 13 volts, and if it is even slightly discharged, it will be something less. The only way you can charge a battery is to connect an electrical source to it that is a HIGHER voltage than the fully charged battery; that is why the charging system operates around 14 volts.

 

So when the engine is running, the charging system has more EMF (electromotive force, or "pressure") than the battery, so as long as the voltage from the charging system is greater than the actual voltage in the battery at any point in time, it is completely impossible for any current to flow OUT of the battery. If a sudden load is applied (like hitting an air horn), that will suck up all of the available current from the charging system, thus lowering the voltage from that "pump" and the battery will then be able to supply the rest of the needed current for this big load. But as soon as the load goes away and the voltage from the charging system goes back up, the current at the battery will reverse direction and flow back into the battery to bring it back up to full charge.

 

The regulator in the charging system is simply designed to sense when the battery has reached full charge and lower the charging system output to only provide the total current needed by the vehicle. In this state, absolutely no current is either flowing IN or OUT of the battery. This is why an ammeter will always show 0 amps if the battery is fully charged and the charging system is still working. If it did not do this by lowering the output voltage to the point where the resistance of the battery was equal to the force from the charging system or limiting the available current (which effectively lowers the voltage), the battery would be constantly over charged and be ruined in short order.

 

In a vehicle with a bad battery that can never reach full charge, an ammeter will ALWAYS show some positive reading because some current will constantly be flowing backward through the battery as if it was being charged. In the old days before sealed batteries, this resulted in rapid water loss from boiling, which further damaged the battery in quick order. With modern batteries, they can live in this status much longer before total failure, but they are still in the checkout lane.

Goose

 

BTW - just to add a little more info on charging systems - an alternator, such as most cars use, has electromagnets, so when the system needs less current, the regulator reduces the voltage to the electromagnets, thus reducing the output. Since this also reduces the magnetic resistance in the turning motor, the fuel mileage increases (by a small amount) when you use less electricity. On our system with permanent magnets and a stator, the stator windings always produce the maximum available current for any particular RPM, so the regulator must operate in a very different way to limit the voltage in the system. Instead of reducing the total generated power, our regulator just shunts all unneeded current to ground. In this type of system, total electrical usage can have zero impact on fuel mileage.

Edited October 2, 2010 by V7Goose
spelling

[Dano]

Gotta agree with the Goose on this one, being an electrician for over 30 years teaches you a couple of things. Just like two football players across the line from each other, the one with the stronger force will always carry the load.

[Seaking]

Awesome, what an educational thread!

 

And here I was all these years believing that electricity worked under the principle of "smoke" ... the more smoke you allow to escape from a circuit the more expensive it is to put back into that system..

 

Hmm might not be the same on a bike I guess.. but this does apply to electronics.. really, it does..

[GeorgeS]

There were two other guys that reported haveing charging problem's this year.

 

They pulled that plug out, and visual inspection looked OK. However, a Resistance check thru the plug proved otherwise. One guy found the wires burnt off at the Crimp Point, of the Pins to the wire ends.

 

As I recall, he had to completly rebuild the plug. Not an easy job.

[Guest PlaneCrazy]

I am sorry, but you are wrong. In fact, what you describe is not even electrically possible, since the charging input wire must connect to the same post on the battery to which the bike load connects. Here are the facts about electricity:

 

Voltage is the force that pushes the electrons through the wire; you can think of it like water pressure. Current is the actual flow of the electrons - how much flows is a factor of the pressure behind it and the resistance in front of it; this is similar to the water in a hose. The amount of water that comes out of a hose is controlled by BOTH the amount of pressure behind the water and the size of the opening at the end of the hose. If you connect a hose to two different pumps, the one with the highest pressure will push water through the hose and into the other pump, despite the fact that the lower-pressure pump is still trying to push water at the same time.

 

The electrical system on a vehicle is essentially the same, with the battery and the charging system both being pumps, and the vehicle load connected between them. The pump pressure of the battery can never be more than 13 volts, and if it is even slightly discharged, it will be something less. The only way you can charge a battery is to connect an electrical source to it that is a HIGHER voltage than the fully charged battery; that is why the charging system operates around 14 volts.

 

So when the engine is running, the charging system has more EMF (electromotive force, or "pressure") than the battery, so as long as the voltage from the charging system is greater than the actual voltage in the battery at any point in time, it is completely impossible for any current to flow OUT of the battery. If a sudden load is applied (like hitting an air horn), that will suck up all of the available current from the charging system, thus lowering the voltage from that "pump" and the battery will then be able to supply the rest of the needed current for this big load. But as soon as the load goes away and the voltage from the charging system goes back up, the current at the battery will reverse direction and flow back into the battery to bring it back up to full charge.

 

The regulator in the charging system is simply designed to sense when the battery has reached full charge and lower the charging system output to only provide the total current needed by the vehicle. In this state, absolutely no current is either flowing IN or OUT of the battery. This is why an ammeter will always show 0 amps if the battery is fully charged and the charging system is still working. If it did not do this by lowering the output voltage to the point where the resistance of the battery was equal to the force from the charging system or limiting the available current (which effectively lowers the voltage), the battery would be constantly over charged and be ruined in short order.

 

In a vehicle with a bad battery that can never reach full charge, an ammeter will ALWAYS show some positive reading because some current will constantly be flowing backward through the battery as if it was being charged. In the old days before sealed batteries, this resulted in rapid water loss from boiling, which further damaged the battery in quick order. With modern batteries, they can live in this status much longer before total failure, but they are still in the checkout lane.

Goose

 

BTW - just to add a little more info on charging systems - an alternator, such as most cars use, has electromagnets, so when the system needs less current, the regulator reduces the voltage to the electromagnets, thus reducing the output. Since this also reduces the magnetic resistance in the turning motor, the fuel mileage increases (by a small amount) when you use less electricity. On our system with permanent magnets and a stator, the stator windings always produce the maximum available current for any particular RPM, so the regulator must operate in a very different way to limit the voltage in the system. Instead of reducing the total generated power, our regulator just shunts all unneeded current to ground. In this type of system, total electrical usage can have zero impact on fuel mileage.

 

 

Oh well, I've just had a crappy day with getting my Venture home so I don't want to argue too much about it but i will say a few things... from the perspective of a licensed Aircraft Maintenance Engineer with 17 years experience as well as an amateur bike mechanic (with course, lol)

 

Voltage is NOT power... Voltage is the Potential (as you say) and current is the actual amount of electrons that flow... It's like they say, it's not the voltage that kills you, it's the current. The charging system in a bike just doesn't have the capacity to run all the loads when they spike. Just because the regulator might be up to 14.5 volts, doesn't mean it's going to take over the load from the battery. The battery has more capacity. So if there's a sudden demand on the system, a battery at 9 volts cranking out 150 amps is sure as hell going to be providing more total POWER then a stator that can that do, say, 400 watts at 14.5 volts. That's only about 27 AMPS. The battery is providing 1350 watts! Power = Voltage x Current.

 

To use your water pressure analogy... Think of the Battery as a reservoir sitting on a hill with a 6" water main feeding the City below (bikes systems). The charging system is more like a 45 gallon drum sitting above the reservoir and feeding it with a 1" hose. What happens when someone opens a fire hydrant down in the city? You think that the regulator is going to provide all the water just because it has higher pressure? Well, I have a pressure washer the size of a suitcase and it kicks out water at 1600 psi... Turn it on full blast and hold it in one drum... then turn on a simple water hose at 30'ish PSI in the another drum... Guess what? The water hose will fill the drum up first. That pressure washer is pumping water out at a huge pressure, but very little over all flow.

 

This is the reason that in almost all charging systems, the output from the regulator goes directly to the battery. The battery isolates the regulator and prevents the loads from hurting it. All loads on the bike originate from the battery and travel through the systems and then out through the frame ground back to the NEG terminal on the battery. (unless you're British, which, in that case, just reverse everything) It's also the reason that if you neglect to address battery problems, you may soon find yourself with regulator and charging system problems as well.

 

I deal with $5000 batteries at work every day. We replace them on our aircraft every 500 hours and send them out for deep cycle. One of the checks I have to perform is a load analysis on the battery. We do an turbine start on a fresh battery and see what sort of voltage drop we get. The systems on most large aircraft are 24 VDC, but the battery usually sits around 27.5 volts. During an engine start, there's about 1500 amps being drawn from the battery and the voltage will normally drop to 22 volts. Any lower and i reject the battery. In fact, that's the only true, accurate way to test a battery.... under a controlled load for a set time. Voltage means nothing as a measure of battery health unless it's under load.

 

Anyhow, I should never have opened my mouth... Explaining basic electrical theory to the average layman is a futile gesture at best.

[Guest PlaneCrazy]

I just wanted to add... Sorry if I offended anyone. I'm a little abrupt this afternoon after a hellish day getting my bike back from a friend's place. And electrical problems are a difficult thing to explain, even among the "experts" ... Just look at the difference between conventional and modern electrical theory... even the big brains couldn't get it right the first time

[V7Goose]

Have it your way; there is obviously nothing I can tell you. I just hope that people who really need to understand these systems don't waste their time believing your ideas . . .

 

You do not understand what you are talking about, neither are you very good at guessing who a layman.

Goose

[Guest PlaneCrazy]

Have it your way; there is obviously nothing I can tell you. I just hope that people who really need to understand these systems don't waste their time believing your ideas . . .

 

You do not understand what you are talking about, neither are you very good at guessing who a layman.

Goose

 

Oh well, it sucks for my company who depend on me to maintain their multi-million dollar aircraft. I guess I have just been lucky for the past 17 years

[dingy]

I will agree with Goose on his description of the charging system. Much more eloquent than my first post.

 

One reason that I disagree with PlaneCrazy suggestion that the charge current goes directly to the battery is the fact that there is no separate, direct path from the regulator/rectifier to the battery. The wiring harness is arranged such that the reg/rect just ties into the Brown feed wire from the ignition switch some where in the center of the electrical system (grid).

 

If the battery's voltage (charge level) is low, it will draw from the "grid" excess current that the reg/rect is supplying. The reg/rect will supply current, depending on system current needs up to its threshold level, say 30 amps. If the system load requirements are less than this max output of the reg/rect and the system voltage is below the threshold optimum (approx. 13.5V) setting in the reg/rect unit the battery will absorb the excess current to return itself to optimum voltage level. Once the system voltage reaches the optimum level the reg/rect unit starts throttling back on current supplied to the grid by shunting the excess output from the stator to ground.

 

If there is a demand from the grid that the reg/rect unit cannot handle, in excess of its 30 amp output, the needed current is then pulled from the battery to supply demand. This in turn reduces the battery/system voltage, then when the spike on the grid that caused the battery drain is removed, the reg/rect continues to supply full current until battery/system voltage increases to the optimum level.

 

There is no logical way given a motorcycles wiring that all the current could go to the battery, then be dispersed to the grid. An aircraft may be different due to load isolators and relay switching. But there are some stringent safety concerns on an aircraft that are not economically justified to incorporate into a motorcycle.

 

Gary

[Dano]

Oh well, it sucks for my company who depend on me to maintain their multi-million dollar aircraft. I guess I have just been lucky for the past 17 years

 

So then explain to me on the MKI's regulator/rectifier why the brown lead from there goes directly to the fuse block to feed the lights, ignition system and accesories without going thru the battery first. If you need to look at the diagram, it's available as a PDF file under the first gen tech section.

 

Also, if what you are saying is true, then why do they offer different amperage alternators for cars? Why do they not just upsize the capacity of the battery? The batterys job is to start the vehicle, act as a "shock absorber" to the system. You described this yourself when you told us about your load tests. If the battery carries everything, why do they have APUs on the aircraft then?

 

Also stated in your recourse is that you "deep cycle" your batteries. Your systems on the aircraft in no way pertain to the systems on these bikes.

[Guest PlaneCrazy]

So then explain to me on the MKI's regulator/rectifier why the brown lead from there goes directly to the fuse block to feed the lights, ignition system and accesories without going thru the battery first. If you need to look at the diagram, it's available as a PDF file under the first gen tech section.

 

Also, if what you are saying is true, then why do they offer different amperage alternators for cars? Why do they not just upsize the capacity of the battery? The batterys job is to start the vehicle, act as a "shock absorber" to the system. You described this yourself when you told us about your load tests. If the battery carries everything, why do they have APUs on the aircraft then?

 

Also stated in your recourse is that you "deep cycle" your batteries. Your systems on the aircraft in no way pertain to the systems on these bikes.

 

On my wiring diagram, I show the output from the reg/rec going to a splice with 3 paths.. one to the battery, one to the main ignition switch and one to a back up fuse. I don't know how its wired on the 1st gen. Nor did I say it was the same on all systems. I also never said that the Alternator wasn't able to handle the loads under normal conditions. Of course it is... it's designed to handle those loads and a few accessories. But the battery is still essential as the "shock absorber" (or more accurately... an accumulator) to the system. Take the battery out and some vehicles will continue to run... others will die immediately and some will run until there is a heavy load demand and then the charging system will burn out. It's incorrect to look at the battery as just big box that only starts the bike and then the charging system takes over everything... the battery is the heart of the electrical system and it's used constantly.

 

As for deep cycling... Aircraft use Nicad batteries (most large size ones anyhow) and they need to be deep cycled to prevent a memory from developing. We use NiCads for two reasons... one, they have the really nice feature of keeping their voltage level even wehn almost completely dead. A Nicad that is 75% discharged will still put out 27.5 volts. That makes it much nicer for the complex avionics of aircraft. Second, a NiCad can discharge it's energy at a VERY high rate... thousands of amps worth. The downside to NiCad's is they require more regular maintenance then Lead acid types and they are much more expensive then Lead Acid types.

 

DC Systems are DC systems... and you'd be surprised to know how similar some systems are on big aircraft as compared to automobiles (or even bikes) As well, my experience is almost 100% hands on experience... not theory, not classroom and not from some other unrelated trade. I deal with AC and DC systems on a fleet of 24 aircraft on the Line and at the risk of sounding vain, I am one of the best system troubleshooters in my company.

 

Anyhow, I am done talking about this. I apologize again if i offended anyone and I will back out now and continue to Lurk. I'm pretty new here and I will not challenge the old guard anymore.

[dingy]

Anyhow, I am done talking about this. I apologize again if i offended anyone and I will back out now and continue to Lurk. I'm pretty new here and I will not challenge the old guard anymore.

 

I for one do not feel offended.

 

You will find that electrical discussions on here, along with oil and tire discussions generate some varied opinions.

 

Myself, I have an electrical degree, have been trained in circuit level theory and trouble shooting of military aircraft in the Marine Corps, and have 15 years experience in maintaining and designing railroad electrical signal systems including electric traction locomotives. I also have quite a bit of experience designing safety circuitry for industrial equipment. As well I have a hobbyist interested in the electrical systems on our bikes.

 

I have found that the theory side is always about the same, but the practical application of these varying fields often lends itself to interpretation by those involved.

 

This board needs people that are involved and willing to contribute.

 

Gary

[Guest PlaneCrazy]

I for one do not feel offended.

 

You will find that electrical discussions on here, along with oil and tire discussions generate some varied opinions.

 

Myself, I have an electrical degree, have been trained in circuit level theory and trouble shooting of military aircraft in the Marine Corps, and have 15 years experience in maintaining and designing railroad electrical signal systems including electric traction locomotives. I also have quite a bit of experience designing safety circuitry for industrial equipment. As well I have a hobbyist interested in the electrical systems on our bikes.

 

I have found that the theory side is always about the same, but the practical application of these varying fields often lends itself to interpretation by those involved.

 

This board needs people that are involved and willing to contribute.

 

Gary

 

 

That's very true and I am sure part of the problem here is my inability to get what's in my head across in the written language. I'm very hand's on and intuitive at work. And it's funny that I can trouble shoot a system on a Boeing 727, for example, with three 60KVA AC generators running on a triple buss system and yet I get lost trying to figure out how to wire a light switch in a new room in my basement

 

I just feel things went south here and I don't feel up to any more arguing. I won't rage quit and cancel my membership over it though.

[Seaking]

I just feel things went south here and I don't feel up to any more arguing. I won't rage quit and cancel my membership over it though.

 

Please don't do anything like that.. then whom else can I pick on later this winter when cabin fever hits?

 

You're lucky to have worked on new modern aircraft.. I retired from the CAF working on an aircraft older than myself!! egads!

[N3FOL]

There were two other guys that reported haveing charging problem's this year.

 

They pulled that plug out, and visual inspection looked OK. However, a Resistance check thru the plug proved otherwise. One guy found the wires burnt off at the Crimp Point, of the Pins to the wire ends.

 

As I recall, he had to completly rebuild the plug. Not an easy job.

 

Where exactly is this plug located?

[N3FOL]

That's very true and I am sure part of the problem here is my inability to get what's in my head across in the written language. I'm very hand's on and intuitive at work. And it's funny that I can trouble shoot a system on a Boeing 727, for example, with three 60KVA AC generators running on a triple buss system and yet I get lost trying to figure out how to wire a light switch in a new room in my basement

 

I just feel things went south here and I don't feel up to any more arguing. I won't rage quit and cancel my membership over it though.

 

Don't feel too bad. I've been drilled myself when I made my own comments regarding my favorite Bridgestone tires before. It was very interesting reading each others post. In my case when it comes to troubleshooting DC problems, I keep it simple especially when I try to explain it to myself.