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Never heard of it on an RC but I’ve replaced a pickup coil on a Kawi cruiser and a Yamaha cruiser in the last couple of years and talking to a dealer tech they do fail more often than you think. It’s sitting right there where it gets plenty hot and probably at 400 ohms if similar to the ones I replaced. You might want to get your motor up to operating temp & do your pulser coil test again.
 

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I'm getting an irritating misfire when I'm working the bike hard in the canyons and mountain roads.
Bike temp is averaging 180F, and it starts happening at about 3000 feet elevation.
I live at sea level, but I've been riding my bike in these same areas for years, this problem is new. Same PC3r and same fuel map-Kyle's Sato lowmount map.

Symptom:
Starts cutting out slightly at about 7000-7500. Continues cutting out till about 8000+.
Stops cutting out from 8000 and up, and seems fine below 7000, altho I feel slight occasional surging at a steady speed.

What I've done:
Replaced spark plugs, and air filters.
Honestly, I can't really 'feel' a difference, but they were due.
First pic is the old plugs, with about 7500 miles on them. Second pic is the new plugs with 250 miles on them. Do they look ok?
The fpr is new, but I checked it anyway, even put a little vacuum on the nipple - it held rock steady at 9Hg.

This is where I need help.
My line of reasoning is to check the following:
Bypass PC and ride the bike to see if that changes it.
While I have the tank raised, I'll check all the fuel injector connectors and pulse gen connector. I'll check coils, ECU, and CDI connectors.

Somehow I feel like it's not connectors.

Other facts about my bike:
2000 SP1 that's been well maintained for the last 10 years and 35,000 miles. It's at 51,000 now. Regular fluid changes, valve inspections, etc. My PC3r is at least 12 years old, but is secured snuggly in tail. Not bouncing around.

Suggestions and input appreciated. :smile2:
Do you feel a power fade or flattening off before the misfiring begins?
If so, you may be having a region of lean AFR.

The surging may also indicate a lean region where the AFR is over 14.7 at steady throttle, which can happen.

Hard to tell, but the new plugs appear a bit on the lean side, with a very, very light tan color.
Usually the normal plug color is a light tan to honey color on one end of the spectrum, to a light gray on the other end of the spectrum.

Does this happen at lower altitudes as well?
If not, you may hypothetically be having an issue with one of the two baro sensors (snorkel or throttle body) not compensating for higher altitude.
The baro sensors are identical, and can be swapped for testing.

Usually, the uncompensated AFR goes to the rich side at altitude, but maybe something is causing the system to over-lean out the fuel (strictly hypothetical).
The FPR check was a good move (though a bad FPR tends to add more fuel).
The throttle body vacuum via the hose to the FPR diaphragm causes fuel pressure changes to compensate for altitude changes as well.
A check if the vacuum hose is clogged may be prudent.

If you experience the same issues at sea level, you might need to have a dyno run to check the AFR settings again to make sure something hasn't gone awry with the fuel map.
 

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Discussion Starter #23 (Edited)
Just to catch up here, aside from the new plugs, air filters, oil, and coolant, (and a recent valve clearance check) - I have done the following:

1. Tested peak voltage to the coils, about 170V each.
2. Tested pulse gen connector voltage and also at the yellow wire in the gray ECU plug. Both the same, about 15V. Seems pretty high for the 18 gauge wires?
3. Inspected and cleaned all related ignition system connectors with electric cleaner. Except the connectors at each injector. Without removing the throttlebody, they're really hard to get to.
4. I tightened the boots under throttlebody, (the manual calls them insulator band screws).
5. Mighty Vac tested all the vacuum lines.
6. I tried to test the resistance between primary and secondary windings in coil, but I couldn't get it to work, nor do I have any spec numbers. I think I got about .7 Ohms on one try.
7. Disassembled spark plug wires, tested the leads, and inspected the cap's inside contacts. All good.
8. I tested the stator resistance, got about .4 - .5 Ohms across the three pairs of spades.
9. Reg/rec output 14.6V to 14.85V, idle to 5000 rpm.
10. After checking the PC3r fuel map, calibrating the PC3r Throttle position, and checking it's connectors - I hooked it back up before my last two test rides. It's still hooked up.

So far, everything is checking out fine.

The problem at 7500 rpm has gone away for now.
In fact the bike has full power and behaves as it should in every instance except one - occasional stalling at idle, and definitely tries to stall every time I let the clutch out to start the bike moving from a stop. I have no power and if it doesn't die, it may run on one cylinder until it catches up with itself. And I'm feathering the clutch the whole time. Once I'm moving and shift to 2nd, everything straightens out and she runs strong.
I was going about 45mph, shifted into 6th gear to drop the rpms to about 2500, then gave it the gas to see if it will stumble. It doesn't.

Summing up, now the problem seems only to be in the 1300 - 2300 rpm range when under load, and randomly at idle in neutral.
I'm not sure what to do next.
Should I pull the throttlebody so I can get to the connectors?
This still feels like an electrical issue to me, but I just don't know.

Per Wibbly's advice in another thread, and the service manual - I'll check into my kill switch, sidestand switch, neutral switch.

@Enxss, I haven't run the bike in the dark yet. That's on the 'to do' list as well.
 

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Discussion Starter #24 (Edited)
OK, the Vdc values look good, but did you also test the altenator resistance and Vac output (over the yellow wires)?

The altenator gets "cooled" by engine oil and as things get hotter and hotter this may affect the unit. Espcially if it in a deteriorated state.
I bypassed the AC output test, based on the results of the resistance test and the reg/rec output test. The engine was good and warm.

Do you feel a power fade or flattening off before the misfiring begins?
If so, you may be having a region of lean AFR.

The surging may also indicate a lean region where the AFR is over 14.7 at steady throttle, which can happen.

Hard to tell, but the new plugs appear a bit on the lean side, with a very, very light tan color.
Usually the normal plug color is a light tan to honey color on one end of the spectrum, to a light gray on the other end of the spectrum.

Does this happen at lower altitudes as well?
If not, you may hypothetically be having an issue with one of the two baro sensors (snorkel or throttle body) not compensating for higher altitude.
The baro sensors are identical, and can be swapped for testing.

Usually, the uncompensated AFR goes to the rich side at altitude, but maybe something is causing the system to over-lean out the fuel (strictly hypothetical).
The FPR check was a good move (though a bad FPR tends to add more fuel).
The throttle body vacuum via the hose to the FPR diaphragm causes fuel pressure changes to compensate for altitude changes as well.
A check if the vacuum hose is clogged may be prudent.

If you experience the same issues at sea level, you might need to have a dyno run to check the AFR settings again to make sure something hasn't gone awry with the fuel map.
Thanks SubSailor. I should have thought to blow thru the lines when I vac tested them. Thanks.
I tested with and without the PC3r, same results. I too was interested in what values my map was running. I've always used Kyle's lowmount sato map.
Here's a picture of it, and the same application map from DynoJet.
 

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Discussion Starter #25
I did a little more on the bike tonight.
Vac lines are clear and sound.
Sidestand switch is good.
Neutral switch checks out ok.
Kill switch and Start switch are good.
Clutch switch is good too.
All 4 injector connectors and wiring are clean.

I had fun with the start/kill switch. You have to get the wires just right to get it back together. :smile2:
 

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Just to catch up ...

2. Tested pulse gen connector voltage and also at the yellow wire in the gray ECU plug. Both the same, about 15V. Seems pretty high for the 18 gauge wires?
To help confirm your test results I performed a Peak Voltage Test (PVT) on my own bike, a 2001. Both the 2000 and 2001 model years use the same Ignition Pulse Generator (IPG). I performed the test using equipment similar to your own, namely a Digital Multi-Meter (DMM) with a 10 meg-ohm impedance equipped with an Electronic Specialties model 640 Direct Voltage Adapter (DVA). The readings were taken at the Yellow wire leading from the IPG and terminating on the Gray Connector at the Engine Control Module (ECM). The Gray Connector was disconnected from the ECM at the time of the test so as to unload the IPG. See attached images.

The test results are similar to your own. The readings ranged from approximately 13 volts to 14 volts, with an average, of say, 13.5 volts. As discussed previously, as long as the PVT shows a value above the minimum requirement of 0.7 volts all should be in order. The reason for this is two fold. Firstly, the service manual states a minimum value of 0.7 volts because this is the minimum threshold required to trigger a solid state device, such as a transistor. The same value is given for other components such as the Cam Pulse Generator (CPG), see page 5-43. It is true that a reading of ~ 13-15 volts may saturate such a device, but this is of no concern.

Secondly, it is the Timing and the Duration of the pulses produced by the IPG that the ECM uses to synchronize the ignition pulses to the engine's speed (RPM). As long as the output of the IPG is above the minimum threshold voltage of 0.7 volts the ECM will sense the pulse along with its timing and duration and process it accordingly.

Regarding the voltage being excessive for the gauge of wire being used, remember that it is not the voltage alone that determines the required wire gauge. Rather it is the amount of energy, or power, that will be transmitted along the wire. Power is a function of both Voltage and Current. A 15 volt reading may appear high for a 12 volt electrical system but the low level of current produced by the IPG, combined with a very short duration pulse, means that very little energy is actually being transmitted along the wire. So despite the voltage level, the wire gauge is more than sufficient to handle the amount of power actually being transmitted.

6. I tried to test the resistance between primary and secondary windings in coil, but I couldn't get it to work, nor do I have any spec numbers. I think I got about .7 Ohms on one try.
I am not sure what you are trying to measure here. My understanding of the ignition coil is that there is no direct electrical connection between the primary and secondary winding. Energy is transmitted from the primary winding to the secondary winding via Induction. When a current flows through the primary winding a magnetic field develops around the winding. This magnetic field, or flux, induces a voltage in the secondary winding as it expands and contracts in response to ignition pulses received from the Converter Unit (CDI). Because there is no direct electrical connection between the two windings the resistance measurement should always be, theoretically, infinite.

As a test of the ignition coils you could measure the resistance of the primary winding for each of the ignition coils you have and compare each with the others. The same can be done for the secondary winding. But I believe this is the extent of such testing.

The problem at 7500 rpm has gone away for now.
In fact the bike has full power and behaves as it should in every instance except one - occasional stalling at idle, and definitely tries to stall every time I let the clutch out to start the bike moving from a stop. I have no power and if it doesn't die, it may run on one cylinder until it catches up with itself. And I'm feathering the clutch the whole time. Once I'm moving and shift to 2nd, everything straightens out and she runs strong.

I was going about 45mph, shifted into 6th gear to drop the rpms to about 2500, then gave it the gas to see if it will stumble. It doesn't.
This almost sounds like a timing issue. As discussed previously, the timing for the ignition system is controlled by the Ignition Control Unit (ICU) which is an integral part of the ECM. The ICU takes the signal received from the IPG and processes it into two signals, one for the front cylinder and one for the rear cylinder. In the process it also adjusts the timing of the output, Advancing it or Retarding it as necessary, based on engine speed (RPM). It is possible that the ICU portion of the ECM is failing resulting in improper timing. You can test this by verifying the engine's timing with a timing light. See Page 17-9. Keep in mind, however, that your PC3R also has the capacity to adjust ignition timing. Should you get a faulty result with the timing light while the PC3R is connected you may want to perform the same test a second time with the PC3R disconnected to verify the result.

... I haven't run the bike in the dark yet.
When you do eventually run the bike in the dark to check for possible High Voltage Leakage from the Secondary Winding of the Ignition Coils and the Spark Plug Wires, if you do not initially see any leakage you can try lightly misting the components with water from a spray bottle. The water mist can sometimes help to reveal the leakage.
 

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Discussion Starter #27
Well...
This got put on hold for a while, I'm picking up where I left off with the thread.
@Enxss I haven't done a timing light yet. thanks for that idea.
 

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Discussion Starter #28
Another update: I ordered some clean used 600rr coils and harness to do the COP conversion. I'm suspect of the rear coil. The old high tension wire had a spot that felt welded solid right where it routes over the subframe towards the cylinder head. Fingers crossed..
I didn't do a timing light, but compression tested good at 172.
Coils should arrive next friday.
 

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We need to go on another ride Jondog, when you get your issues worked out! Went on a short ride last week through Sutter, Plymouth, and out through Volcanoville. Some nice roads out there! It was much needed during all of this BS. Hung out in front of the general store in Volcanoville for a break, nice Lady inside was making sandwiches. Had a back to normalcy feel there for awhile anyway. We hooked up with a guy from Chicago, who now lives in Folsom, at a gas station. He was riding a VFR800. He's loving the roads out here in Ca., and will probably ride with us again in the future. His exact words were "I love it out here, even the roads that LEAD to good roads, are good roads!" Nothing but flat out in the windy city apparently! Lets get the Pig Crew back together, for another one!
 

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Discussion Starter #30
I have another issue I just discovered yesterday. The front starter valve adjuster was disengaged from the linkage. No idea how it got that way, the last time I touched it was to clean the dust and grime off the pivot points many years ago. I discovered the fork that pulls the valve in and out is very soft metal and it spread apart and let go. So I did a little surgery and got the linkage hooked back up. According to the manual, the front valve should be adjusted to 0.8 in Hg more than the rear.
Has anyone adjusted their starter valves?
Will my standard vacuum gauge be detailed enough to set the front valve?
As soon as my COP's arrive, I should be able to install them and get the bike warmed up again to set the starter valves. Looks like Friday...
 

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Discussion Starter #31
The problems that I had when I started this thread, I feel have been solved now.
The high rpm misfire was probably a bad connection at the throttle position sensor that I discovered.
The stalling and misfire from standing start seemed to be my coils. I scored a set of four 600rr COP's and harness for $50 from a bike breaker on ebay. Absolutely zero stumbles now when I start the bike rolling in first gear. Ya!

Thank you to all who contributed in this thread. I used a lot of the advice, and learned a ton about my bike!
I have another issue currently, but I think a new thread may be appropriate since I feel like the problem may not be related to this one.
 
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