Right carb is sucking and producing no power

Castle551

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So I think I’ve found some electrical gremlins. I’m cleaning and adjusting my points as shown in the video by, A Motorcycle Nut. According to my multimeter, with the key on, I’m getting pretty continuous continuity even with the points touching. I’m using one of the fins as a ground. I tried also using his lightbulb trick. Is my process correct?

When I opened up the cover, I found that the cam was clean and in good shape and my ignition plate is clean. I gapped my points to .014 and the right might have been a little loose, but not by much.
 
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jpdevol

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Absent a strobe, unhook points wires @ coil connect multimeter there (one @ a time) and ground other probe. Points open = no continuity, points closed = 0 Ohms or buzz (the ones with buzzer on Ohm function make it easier). You're looking for points to just open as rotor passes F mark in normal rotation.
 

grizld1

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That is not the whole drill. If the advance governor (AKA Automatic Timing Unit) has worn bobweight tips, the advance curve will be stretched, and setting retard timing correctly will put you in piston holing country at full advance. After you dial in a points set to the F mark as described, hang a box end wrench on the points cam nut to pull the cam and rod to the full advance position and check again. Points should open at or slightly to the right of the leftmost mark. Stroboscopic timing lights aren't very expensive, provide much more information, and and leave much less room for error than static timing.
 

jpdevol

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Just trying to keep it simple, with known tools at hand, to diagnose a dead right cylinder. Didn't mean to underplay the benefits of a strobe (and they are cheap).
 

grizld1

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I've seen too many holed pistons due to owners/shop mechanics who set points at full retard and called it good. No offense meant to Castle, but it's pretty clear that some critical maintenance has been neglected. For one thing, the advance rod has probably not seen fresh grease since it was installed at the factory.
 

Castle551

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The standard max is 0.1V per switch and connector. If you're seeing a full 1V drop, make sure of power out from the key switch. You don't want to see a big drop going to the regulator; the regulator will "read" the drop as a low charge condition and overwork the alternator rotor, with the potential for serious damage. I don't like to see more than 0.25V drop from battery voltage anywhere.
Hello grizld1, so I just tested that red and white wire from the coil with the ignition on. Battery is showing 12.42 volts and the red and white wire is showing 11.46 volts. Is this adequate, or should I suspect to find a problem upstream of that wire?
 

arcticXS

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That is
Hello grizld1, so I just tested that red and white wire from the coil with the ignition on. Battery is showing 12.42 volts and the red and white wire is showing 11.46 volts. Is this adequate, or should I suspect to find a problem upstream of that wire?
That is 1 volt of voltage drop. I hope that is with the corresponding set of points closed. Even so, it is still bad. If it is with the points open, it is horrible.
 

Castle551

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That is
That is 1 volt of voltage drop. I hope that is with the corresponding set of points closed. Even so, it is still bad. If it is with the points open, it is horrible.

Just checked again. With the points open and the key on, it’s measuring at roughly 11.80 volts. This is with the battery hooked up to a tender throughout testing. Is the next step just to start unwrapping wire bundles and look for shorted wires? Or where would you suggest?

At this point, I’ve gapped my valves, replaced spark plugs, and cleaned carbs. I bought a ignition strobe that I’m still learning how to use, but it seems with the red and white wire testing low, that dynamically adjusting my points will come after solving my drop in voltage.

Thanks everyone for trying to help. I really appreciate your responses.
 

5twins

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Voltage drop is usually caused by one (or more) of the connections and/or switches in the power path from the battery to the coil. So, I would work backwards from the coil, testing voltage in and out at each one of those points. The path backwards would be from the coil to - kill switch, ignition switch, main fuse, battery.
 

arcticXS

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I'd clean the kill switch, ignition switch, and ALL bullet connectors involved in the power from battery to coil. If you lose 1 volt or more from battery to coil+ with the points OPEN, it is an extremely poor connection somewhere.
On a healthy system, with a battery voltage at 12.6V, the voltage at coil + should be well above 12V with the points CLOSED. In that state, the coil should draw a current of around 3A. With the points OPEN, and zero current draw, the coil + should read the same voltage as the battery.
A points and coil ignition system is actually a very simple setup to troubleshoot......
 

Castle551

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I’m trying to follow the other as suggested and I just discovered that the problem seems to lie somewhere inside the headlight. With the key on, and the headlight on, I was “fondling” the rats nest and the neutral light, high beam light, and the headlight keep going on and off. I guess I’ll start by cleaning all the connections. Thank you for that ignition switch thread! I’ll dive into that as well.
 

5twins

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That ignition switch thread won't help you much because it's for the Special switch with the fork lock built in. Your Standard switch is different, only a switch with no fork lock, and it's crimped together. Besides, that guy didn't do a 100% renovation, he didn't disassemble, clean, and lube the lock cylinder itself, the part the key sticks into. Most of them are in dire need of a cleaning as well. So, here's a better link for you. The 1st three posts cover renovating the lock cylinder and your Standard ignition switch is covered in post #8 .....

https://www.xs650.com/threads/locks-and-keys.60861/
 

Castle551

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Ok, so I have untangled and cleaned most of the connections in the rats nest behind the headlight. The red live wire coming from the battery going to the ignition is Testing 12.5-6ish volts. All wires leaving the ignition are testing 11.85-11.90V. Is this a big enough drop to warrant overhauling the ignition switch?

Ultimately, is this a large enough drop in voltage to explain my dead right cylinder?
 

5twins

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It seems most of your loss is from there (.6 to .7 volts). I would clean it. This is a cumulative effect thing. Loss of a few tenths of a volts from several connections or switches all adds up. I'd check the kill switch too. No, I don't think it's enough to explain or cause a dead cylinder.
 

teamWicked

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Cleaning the ignition switch contacts is pretty straight forward. Have a work surface nearby to set the pieces down on.
 

jpdevol

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Ok, so I have untangled and cleaned most of the connections in the rats nest behind the headlight. The red live wire coming from the battery going to the ignition is Testing 12.5-6ish volts. All wires leaving the ignition are testing 11.85-11.90V. Is this a big enough drop to warrant overhauling the ignition switch?

Ultimately, is this a large enough drop in voltage to explain my dead right cylinder?
Perhaps we skipped a step between now and mid-July (and started checking voltage); did we ever verify that points were opening and closing continuity to ground (esp. RH) and verify timing?
 

teamWicked

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Perhaps we skipped a step between now and mid-July (and started checking voltage); did we ever verify that points were opening and closing continuity to ground (esp. RH) and verify timing?
This ^ and VM or BS38. Here is a question. If VM, after playing with it have you set the idle screw in far enough or checked sync. If BS38, you had to mess with the linkage and sync would be off.
 
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