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Discussion Starter #1
Let me preface.

I'm completely new when it comes to bikes and I decided to go with a project bike because of the cost and because I wanted to learn all I could.

The engine is a 2010 750 shadow and the frame is a 2000 frame. The owner told me the wiring harness is from a 2010 aswell.

The problem is no spark on any of cylinders
The spark plugs are brand new and the plug caps are in great condition.

This leads me to believe it's the ignition coils causing the problem. However, I am unsure as I don't know how to properly test the coils as there were no videos on youtube testing this type of coil. So I'm unsure of what's a red flag. Both coils tested the same

When I connected both the primaries to a multimeter both read about 3.5k
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When I connected both the secondaries it read about 21.3k
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When I connected the primaries to the secondaries I got no reading
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If the coils are fine another issue could be the ignition switch. Right now there is no ignition and only a switch connected to the two wires
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This turns on the whole bike and I can turn over the engine with it so I don't know if it's the problem. The actual ignition I bought is aftermarket and it says its for a 2010 shadow however it confuses me because it has extra wires
Sensitive content, not recommended for those under 18 Show Content
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This is the battery
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There are also these extra wires I assume go to the tail light/blinkers
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Anyway thanks in advance for all the help. It all is very much appreciated as I'm beyond excited to ride this as my first bike!
 

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Look thru this thread for the manual for your bike:

Probably find the answers to all your questions there,
:)
 

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1983 Honda vt750 Shadow
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Your coil readings are pretty much OK. I have some of those Harbor Freight meters too and they do not go down to 00.00 ohms when on the lowest scale.
So put it on that 200 ohm scale and touch your meter leads together. If it shows around 1.2 or1.5 ohms or so, you have to subtract that from your primary reading. Then it will probably be in the ballpark of around 2 ohms.
The others are OK.
When the key is on you should have battery power to the black/white wires on the primary connectors.

And those wires look like turn signal colors.The greens are grounds.

What concerns me is that it is a 2010 engine so it is fuel injected and I see the pump hanging down the side of the frame. And a return hose should be connected on one of those nipples.
Did you ever hear it run ???
 

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Discussion Starter #4
Your coil readings are pretty much OK. I have some of those Harbor Freight meters too and they do not go down to 00.00 ohms when on the lowest scale.
So put it on that 200 ohm scale and touch your meter leads together. If it shows around 1.2 or1.5 ohms or so, you have to subtract that from your primary reading. Then it will probably be in the ballpark of around 2 ohms.
The others are OK.
When the key is on you should have battery power to the black/white wires on the primary connectors.

And those wires look like turn signal colors.The greens are grounds.

What concerns me is

Your coil readings are pretty much OK. I have some of those Harbor Freight meters too and they do not go down to 00.00 ohms when on the lowest scale.
So put it on that 200 ohm scale and touch your meter leads together. If it shows around 1.2 or1.5 ohms or so, you have to subtract that from your primary reading. Then it will probably be in the ballpark of around 2 ohms.
The others are OK.
When the key is on you should have battery power to the black/white wires on the primary connectors.

And those wires look like turn signal colors.The greens are grounds.

What concerns me is that it is a 2010 engine so it is fuel injected and I see the pump hanging down the side of the frame. And a return hose should be connected on one of those nipples.
Did you ever hear it run ???
I have never heard it run and the return hose connects to where? Also the ignition switch turns on whole bike it does not have a key. Also are the coils good? Do the primary and secondary coils not connect? Also I connected the two primary connectors with the multimeter and I got no reading. I'm wondering if the coils are even getting power.
 

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The return hose comes off the fuel pressure regulator at the fuel rail as a fuel return circuit after the regulator adjusts the pressure to the injectors.
The coils look good from here. The primary and seconday DO NOT connect. These coils are like a transformer with separate windings.
The two primary connectors should be around 2 ohms +/- when you put you meter on the 200 ohm scale and subtract the false ZERO that those meters have. The secondary is 20-30,000 ohms so you have to change to a higher scale as you did in the picture.
 

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I think you better get a manual and study it.
And I hope you got the bike free or super cheap.Fixing other peoples hack job will be tough.
Here is a good Honda manual that will give you info on the EFI system.

 

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Discussion Starter #7
The return hose comes off the fuel pressure regulator at the fuel rail as a fuel return circuit after the regulator adjusts the pressure to the injectors.
The coils look good from here. The primary and seconday DO NOT connect. These coils are like a transformer with separate windings.
The two primary connectors should be around 2 ohms +/- when you put you meter on the 200 ohm scale and subtract the false ZERO that those meters have. The secondary is 20-30,000 ohms so you have to change to a higher scale as you did in the picture.
Ok thanks, so will the fuel pump even turn on without one of the hoses connected to the regulator because that's another problem is I don't think any fuel is reaching the engine. I might've gone on a wild goose chase with the spark as my mechanic friend we sprayed some brake cleaner in the air intake to see if it would atleast start but it did not so that's how I came to the conclusion of no spark. We then tested it by grounding one spark plug by touching it to the engine with the other spark plug out and it did not spark. However, after seeing the diagram you sent of the ignition coil it probably didnt spark because the other plug wasn't in. Now I'm starting to wonder if I actually do have a spark. Is there an easy way to test it? Thanks again!
 

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Easiest spark test is just like you did.
If the coils have battery power on one primary terminal, and the other terminal gets the signal from the ignition control unit it should have spark.
I thought about the hoses to the pump. One has to be the feed line from the tank, and the other is the return line.
The hose with the special snap connector is the pressure line to the injectors. Up to 50 pounds pressure out to the injectors. So 3 hose connections and the plug for power.
 

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Discussion Starter #9
Easiest spark test is just like you did.
If the coils have battery power on one primary terminal, and the other terminal gets the signal from the ignition control unit it should have spark.
I thought about the hoses to the pump. One has to be the feed line from the tank, and the other is the return line.
The hose with the special snap connector is the pressure line to the injectors. Up to 50 pounds pressure out to the injectors. So 3 hose connections and the plug for power.
Ignition control unit? Like the ignition itself or is the a computer of some sort. Also what would cause the coil not to get power and or the fuel pump because when I attempted to start the bike last time I did not hear the fuel pump whirrrr on. Also here is the fuse box as I bridged some fuses and idk if that might be the issue
290070
 

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On that F.I. bike the computer would handle fuel and ignition too.
Better study the manual, you have your work cut out on that one.
 

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Hmmmm...If that’s a 2000 ACE frame with a 2000 gas tank it’s not going to have the same feed and return connections for a 2010 Fuel injection setup, so that could be an interesting issue as well. All 2000 model 750 frames would have been for a chain drive, and I see a chain in the pictures so I’m assuming that’s a 2010 750RS engine with chain drive. There should be a PGM-FI computer plugged in on that harness somewhere.

Here is a link to the entire 750RS service manual. http://www.vt750dc.com/VT750RS.pdf

This is the ignition system diagram for the 2010 750RS
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1999 Shadow 750 ACE VT750CD3 Modified
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This is an interesting project and doable with all wires hooked up right with the complete set of electronics and some fuel line trickery.
I believe on those the PGM/ICM is one combination (Keihin) box with two large connectors, @Froth's wiiring diagram covers half the story the ICM connector, you can't get by using the ACE ICM as it only has half the information even if you hacked it into the system.
The easiest way is probably to look at the parts diagrams, wiring and hose routing diagrams and check off what you have already, what you need and what can be faked.
A fuel injected Aero gas tank is probably worth looking at in detail, otherwise I think one would have to add a couple of lines to the ACE gas tank or fabricate a small sub tank/manifold for the return and supply lines.

I've actually considered stuffing an ACE/Spirit twin carb engine in a VT750RS rolling chassis in the past, the RS is rare around here locally and due to the durability nobody seems to blow them up, so it has remained merely a thought game for me.
 

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I wonder how complete that whole thing is. It needs the sensors and wiring all correct for the ECM to see engine speed, temp,intake air flow, intake temp, throttle position.
All that stuff has to be fed into the ECM for it to run the ignition and spark, timing, idle speed, fuel pump operation,etc.
That what is so involved with F.I.
In the older systems the carb handled fuel, so you diagnose the carb.
The ignition unit handled spark, so you diagnose that part.
Now the ECM has control of all the operations in one box.
 

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Discussion Starter #14
This is an interesting project and doable with all wires hooked up right with the complete set of electronics and some fuel line trickery.
I believe on those the PGM/ICM is one combination (Keihin) box with two large connectors, @Froth's wiiring diagram covers half the story the ICM connector, you can't get by using the ACE ICM as it only has half the information even if you hacked it into the system.
The easiest way is probably to look at the parts diagrams, wiring and hose routing diagrams and check off what you have already, what you need and what can be faked.
A fuel injected Aero gas tank is probably worth looking at in detail, otherwise I think one would have to add a couple of lines to the ACE gas tank or fabricate a small sub tank/manifold for the return and supply lines.

I've actually considered stuffing an ACE/Spirit twin carb engine in a VT750RS rolling chassis in the past, the RS is rare around here locally and due to the durability nobody seems to blow them up, so it has remained merely a thought game for me.
The gas tank has been modified by the previous owner and has a return line as well. What do you mean by faked?
 

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I wonder how complete that whole thing is. It needs the sensors and wiring all correct for the ECM to see engine speed, temp,intake air flow, intake temp, throttle position.
All that stuff has to be fed into the ECM for it to run the ignition and spark, timing, idle speed, fuel pump operation,etc.
That what is so involved with F.I.
In the older systems the carb handled fuel, so you diagnose the carb.
The ignition unit handled spark, so you diagnose that part.
Now the ECM has control of all the operations in one box.
Is there anyway to bypass the ECM and just make the bike super simple.
 

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NOOOOOO !
Unless you go back to carbs and basic sparks, probably the original type engine, with all the correct components.
 
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Is there anyway to bypass the ECM and just make the bike super simple.
No, you absolutely need the PGM-FI ECU/ECM as it has a bunch of checks for sensors that it must do before starting can ever happen, you would need an entire standalone engine control unit like a megasquirt to even attempt to run the engine with some sensors turned off. Electrics are a requirement with fuel injection and there is no cheap workaround.
 

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You need one of these and the wiring that goes to it if you don't already have one hiding somewhere.
Let's hope you really have the full wiring harness.

If you want to start from scratch you could go the megasquirt route as suggested by @Froth or maybe drop an email to the folks at Ignitech Electronic for motorbikes - IgniTech Přelouč, but I think returning to the original setup is going to be easier and probably cheaper, if not as much fun. (-;

Faking things is a matter of supplying signals or value readings to the ECU to keep it happy even though you may be missing something or running it out of spec.
It may be as simple as feeding it a voltage or showing it ground, but it can get far more involved and a project unto itself.
 

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You need one of these and the wiring that goes to it if you don't already have one hiding somewhere.
Let's hope you really have the full wiring harness.

If you want to start from scratch you could go the megasquirt route as suggested by @Froth or maybe drop an email to the folks at Ignitech Electronic for motorbikes - IgniTech Přelouč, but I think returning to the original setup is going to be easier and probably cheaper, if not as much fun. (-;

Faking things is a matter of supplying signals or value readings to the ECU to keep it happy even though you may be missing something or running it out of spec.
It may be as simple as feeding it a voltage or showing it ground, but it can get far more involved and a project unto itself.
Ok thanks, and yes I do have that exact ecu
 

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Then if that ECU works you need to check every circuit shown in the diagram I posted, check all wire colors and make sure connections are strong. You need most of those sensors either working or fooled into sending a “working” signal to the ECU or it won’t fire.
 
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