Weak spark

[Guest]

How big is the spark supposed to be, and what color? I've seen videos of motorcycles with bright blue, vibrant sparks.

 

[Guest]

There are a lot of factors, voltage to the coils, the coils themselves, the light you are looking at the spark in. If you can hear it and see it well it is probably ok. Why don't you spray a bit of starting fluid into the air box and see if it fires. If it does fire up for a few seconds it will run. Then you will have to find out why it isn't getting fuel. Do not use starting fluid for anything but a test. It will wash oil off of the cylinders used excessively and cause damage. Ether in the starting fluid should be able to get enough vapor into your carburetors from the air box to fire the motor.

 

[Rob S.]

...bright blue, vibrant sparks.

Sounds proper.

 

[Guest]

Ok, I tried the starting fluid. Sputtered once, but wouldn't start.

 

[Guest]

It's firing then. Check the compression (in the manual) and valve adjustment (also in the manual). If that doesn't do it, the next thing is to make sure you are getting fuel and possibly rebuild the carburetors. Tutorials are on the bikecliff site. http://members.dslextreme.com/users/bikecliff/

 

[Guest]

I've taken apart and cleaned the carburetors 4 times, and even soaked each one in Chem-Dip. Took all the jets out, looked at the float needles (metal-tipped). Adjusted the float tangs down (towards the float needle, I had the carburetor upside down when I did this) so it pushes on the needle sooner. It no longer spills over the bowls, but still seems to flood. I unhooked the vacuum line after letting it sit for 2 days (with everything put back on). Sprayed some starting fluid in, and it started for a bit. Hooked up the vacuum line, sputtered a couple times, and now it won't start. So I'm letting it sit while I charge the battery.

 

[Big T]

It seems that it's time for you to read the carb tutorial and the service manual

 

[Guest]

A lot of the tests I need to do for balance and stuff require the engine to be running, which it isn't. My local major motorcycle shop charges $100 per carb, making mine $400.

 

[BigD_83]

I don't have anything to add except some encouragement. You're getting lots of great advice from OldVet66 and others.

I know it is hard to focus when you get frustrated, and vice versa, but you have to take a step back sometimes and make sure you are following a structured approach to troubleshooting.

Keep at it. You'll get there.

 

[Guest]

Oh, their advice is great, and I'm thankful for it. It's my lack of knowledge and experience. This is my first motorcycle, and thusly my first motorcycle engine I've ever worked on. I feel like I did everything correctly, and then nothing happens. I just took the carburetor off. I'm going to send pictures of the float needles and jets. My original issue that I made this thread for seems to be kinda solved...?

For example, one of the carburetor jets was stuck in its hole. I think it was a needle jet? One of the tiny ones under the rubber plug.

 

[cowboyup3371]

That was the pilot jet. If it was stuck, did you get it out? If not they are not cleaned and you will still need to go back through them again

 

[Wingsconsin]

Oh, their advice is great, and I'm thankful for it. It's my lack of knowledge and experience. This is my first motorcycle, and thusly my first motorcycle engine I've ever worked on. I feel like I did everything correctly, and then nothing happens. I just took the carburetor off. I'm going to send pictures of the float needles and jets. My original issue that I made this thread for seems to be kinda solved...?

For example, one of the carburetor jets was stuck in its hole. I think it was a needle jet? One of the tiny ones under the rubber plug.

Your "lack of knowledge" is changing rapidly -
Stay patient - the hive mind will get you through this.
This bike will RUN again and RUN WELL

 

[Guest]

I got the left coil to spark for a short while, which got my bike running. However, it stopped. When I went to check the wires, the spade connectors came off. I had none to replace them, so I switched to bullet connectors.
Still no spark. Still getting 11.37 volts at the orange and white wires where they go to the connectors to hook up to the ignition coil. However, with the new connectors, there's no spark. When I pulled the white wire out of its connector and touched the copper strands to the metal in the connector, it causes the spark plug tester I had connected to flash. When I wrap the copper strands around the bullet connector (after removing the terminal it was plugged into), no spark. Noob question, but shouldn't simply touching the exposed wires from the harness to the exposed wires from the coil conduct electricity and make the spark plug spark?

 

[Guest]

The kind of connectors you are using are about the worst you can get. The real deal has a set of wings that wrap around the stranded wire and dig into the center of the strands and a set of wings that wrap around the insulation to provide strain relief at the same time. There are covers for the connection terminals. It requires a special crimp tool that is designed for the connectors and the good ones are double action so the crimps are correct for your wire size. The crimps are just like factory crimps. Do it once and forget about it. I think you need to use a terminal where you can see the results of your connection. This site has a decent crimp tool for $32.00: http://www.cycleterminal.com/motorcycle-connectors.html

 

[Steve]

Noob question, but shouldn't simply touching the exposed wires from the harness to the exposed wires from the coil conduct electricity and make the spark plug spark?

No. The spark happens when you DIS-connect the wires.

When the wires are connected and current is flowing, a magnetic field is also created. When the connection is opened (removing the wire, points opening, ignitor opening the connection), the current stops, the magnetic field collapses and the spark is generated.

.

 

[Guest]

New connectors, but still no reliable spark. I got it to spark for a bit, but then I had to charge the battery.

 

[Guest]

This is the reading on my multimeter on connectors with the ignition set to On:

 

[Guest]

While cranking, it shows 7.66.

Also, when I touch the left coil (the one that isn't sparking), it feels warm. I see just the faintest of flashes in my spark plug tester while cranking.

 

[Wingsconsin]

Are those readings Volts ? (VDC)
I believe the bike needs to see at least 10 V while cranking to have a chance to start -
Take your battery in to be tested at a Batteries Plus, or some other auto outlet
(I can't read the setting on the VM - Old eyes )

 

[Guest]

Yes, it's in volts. And it's a new battery.
This is enough voltage to get the right coil to spark, and the left coil will spark intermittently. The problem is getting the left coil to spark reliably.