Installed new ignition coils, now my cb450 won't run :(

I'll have to check when I get home but I'm sure it's at the right level. I might have ruined the battery a bit before due to poor knowledge. I got it towards the beginning of this year. Fully charged, the battery is 12.5V, but PJ said it should be around 13.5V fully charged.
 
I just checked the battery again and after a full charge it's at 13.2v. When I turn the ignition switch on then off, it goes to 12.6V. When I turn the ignition back to on, the voltage is 12.3V, then back to 12.6V when it's off.

Is this the sign of a bad battery?
 
You should see a drop in voltage when you turn it on.. Any lights or electrics that get powered up with the ignition will take voltage from the system (just the introduction of additional wiring will show a small drop as the resistance of the wires will reduce voltage). I'm new to motorcycles and working on them as well, so I could be off base with this, but I fried a good coil trying to get my bike working right this summer because I had it wired wrong. I seem to remember you saying one of the coils was getting really hot in an earlier post, from what I know I think this could fry it. Do a Google search on how to test a coil. It's pretty easy to do, just need an ohm meter (multi-meter).
 
Drain the tank? Is that a metaphor?
;)

When I was working on my coils (relay mod) I just slide the tank back so the front mount things came off the rubber knobs. Then I used a piece of wood to prop the front of the tank up off the frame enough to get easy access to the coils. I didn't disconnect the fuel lines or crossover tubes.
 
Flugtechnik said:
Drain the tank? Is that a metaphor?
;)

When I was working on my coils (relay mod) I just slide the tank back so the front mount things came off the rubber knobs. Then I used a piece of wood to prop the front of the tank up off the frame enough to get easy access to the coils. I didn't disconnect the fuel lines or crossover tubes.
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Why didn't I think about that? Thanks man! But does anyone know about the battery issue if that's normal?
 
goodfornothing said:
But does anyone know about the battery issue if that's normal?
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A good battery, fully charged, not connected to anything should read about 12.8v. If the battery is charging when the bike is running (IE you're getting 13.5+ v at the terminals), the bike should run OK.

Does the bike start up again after it has stopped? Could it be something simple like the fuel tank not venting? I'd check the fuel flow / float bowls when it stops again just to eliminate this.
 
Don't the chain auto parts stores test batteries? Can they test moto batteries?
 
hillsy said:
A good battery, fully charged, not connected to anything should read about 12.8v. If the battery is charging when the bike is running (IE you're getting 13.5+ v at the terminals), the bike should run OK.

Does the bike start up again after it has stopped? Could it be something simple like the fuel tank not venting? I'd check the fuel flow / float bowls when it stops again just to eliminate this.
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How would I check the venting in my fuel tank? When I turn the petcock on, I see fuel flowing into the carbs, but I'll double check that.
 
goodfornothing said:
I have another question, when checking the coils, does the ignition have to be on?
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No, it shouldn't be on at all. The coil test involves testing the resistance of the wires inside, not voltage. I followed a lot of the advice on this site when I was working on mine. Really helped me to understand how and why the electric systems work on these guys.

http://www.dansmc.com/electricaltesting.htm
 
goodfornothing said:
How would I check the venting in my fuel tank? When I turn the petcock on, I see fuel flowing into the carbs, but I'll double check that.
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If the fuel tank cap is not allowing air into the tank, the flow of fuel will create a vacuum inside the tank and the flow will eventually stop.

When the bike starts to struggle, open the fuel cap (not while you're riding it) and see if the condition improves. If the bike goes back to normal, then you have a blocked cap vent.
 
Okay so I finally had time to check out the bike again tonight.

Same thing happened: I started it up, got it to idle, rode for like 2 minutes, drove up the driveway then it stalled. Started it up again and died shortly after.

Here's a video of the bike starting up after it had died a few times prior. (The needle is wobbly because a prong broke on the tach spindle thing)
[youtube=425,350]<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/lGg2uF_Yljc&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/lGg2uF_Yljc&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/youtube]

So I opened up the gas cap and I didn't really notice a different after I started it again. I'll have to re-do it. Next I checked the float bowls for fuel, and yup, it has the right amount of fuel in each carb. I know the idle jets aren't clogged because I got the bike to idle before it died.

Next I checked for spark. Both sides had spark. Here's a video.
[youtube=425,350]http:<object width="425" height="344"><param name="movie" value="http://www.youtube.com/v/qfZrwKB97Ag&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/qfZrwKB97Ag&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="425" height="344"></embed></object>[/youtube]

One side may seem to have more spark than the other. I switched the plugs and the strength of the spark switched as well. Could this be a reason why my bike is stalling? Also, the angle of my iphone camera makes it seem like the right side spark doesn't start right away, but it does.

So I have fuel and spark. Does having spark while the coils are warm and after the bike has died mean the coils are good? I don't really want to bring this into a shop :(.
 
If you're getting spark immediately after the bike dies, then probably not the coils. A bad coil might work when cold, then fail when warmed up. If it sparks when its warm, after the engine dies (immediately, not giving time to cool down) then I'd say the coils are not the issue. I'm by no means an expert though, hopefully someone here can help with the problem..
 
Thanks man, the coils seem to be fine since I'm getting spark when they're warm. I'm going to try hotter plugs because my current 8bes are still fouled.
 
If its fouling plugs that badly its could be as simple as too much fuel. Does it seem as if the motor is flooding? Do the plugs smell really strongly of gas when you remove them? Or are they fouling because there isnt enough fuel? It can look as if the tank/petcock is supplying a correct amout but not be.
http://www.ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp
A screwy air/fuel ratio can do odd things to a motor and how it runs.
 
Also, are you sure the timing is correct, as well as the points gaps, and spark plug gaps? If you have ruled out a bad battery, bad coils, poor fuel flow, and improper grounds, than it would seem that it could be that the ignition system on the bike isnt working properly. How many miles are on the motor? I know that for the 350 twins, a valve adjustment and elec. tune up are called for at 14000 -15000 miles, not sure about the 450s though im willing to bet its within a similar range. Your maunual will tell you the proper gaps and the tolerances needed to run.
 
All timing and pints gaps were set perfectly prior to the new coil installation. The bike runs foe a while before it dies and it ran pretty well too before the coil change.

You might be right about the fuel issue. I might be getting too much fuel in there or not. I mean the flloat levels are correct as well and the bowls don't overflow with gas either. I'm going to run to the auto store right now to pick up some B6ES plugs (which were on the bike when I got it). The manual recommends B8ES but I want to try a hotter plug.
 
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