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I've been working on my cb450 project for quite a while. And now I can get it to start and when I do... I can't make it idle more than a few second. I took my sparkplugs out (iridium) and they do spark but a little weak for my taste. Any idea or advice? I coil cable ignition system plus are all new...
That sounds more like a fuel problem. You could try charging the battery fully first and see if that makes any difference and then I'd turn attention to the carbs
That sounds more like a fuel problem. You could try charging the battery fully first and see if that makes any difference a then I'd turn attention to the carbs
Big enough to ignite the gas in the combustion chamber.
If you say the ignition is new, then it's most likely good. The motor starts, right? Then you are getting decent spark at idle. If it wont stay running, then either your battery is junk or the carbs aren't supplying enough gas/air to sustain the engines rpm at idle.
Big enough to ignite the gas in the combustion chamber.
If you say the ignition is new, then it's most likely good. The motor starts, right? Then you are getting decent spark at idle. If it wont stay running, then either your battery is junk or the carbs aren't supplying enough gas/air to sustain the engines rpm at idle.
Sometime its start... sometime now... i've been pumping it since 3 days now... not starting.
Batterie new... and full
Spark new
Electronic Ignition
Gaz in the tank.
Carb new VM32.
The thing is I can't ajust the carb because the ignition timing is not spot on... and I can't set the Ignition timing because I can't start the bike... :S... I'm screwed now
Don't set your timing with the engine running. You just set your gap on your points then adjust it by turning the Crank to the timing mark and seeing if your timing light is turned on. Turn your points plate untill the light comes on. try doing a google search for a online repair manual for these bikes. If you need more detailed information just ask.
Don't set your timing with the engine running. You just set your gap on your points then adjust it by turning the Crank to the timing mark and seeing if your timing light is turned on. Turn your points plate untill the light comes on. try doing a google search for a online repair manual for these bikes. If you need more detailed information just ask.
Get some standard plugs to set it up.
The iridium are resistor plugs, are you using resistor plug caps with them?
What resistance caps? (5 or 10 K/ohm?)
Your not using carbon 'performance' leads? (they also have specific resistance per foot)
What jetting is in the VM32?
It's probably too rich as NO ONE supplies them correctly 'out of the box'
see the thing is on these cb450's you can't see the timing mark while its running all you do is with the engine not running but the key turned on connect a 12volt light bulb to metal strip coming off of the point and to the engine for ground. then After setting your gap correctly turn the engine so the timing mark is lined up and turn your points plate untill the bulb comes on. The light will light up without the engine running as long as the key is on.
*Edit did not see the Dyna S ignition Comment*
Still try the timing light with it not running but the key on see if it still works that way
Timing can be set statically at the stock F and LF marks or with a running motor to see that it advances to the fully advanced marks. You can also check full advance timing statically. It is not necessary to run the motor to do that. In fact we rarely use a timing light on race bikes. There are very few "must" issues here. Lots of "should" or easiest to" or "recommended" but few obligatory items.
So you have a Dyna S on the cam end. To check timing at full advance, turn the motor to fully advanced position and tun on the ignition (plugs out and lying on the head) Grab the rotor and advance it and see where it sparks. Spark should be fat and blue. Adjust as required.
If the spark is weak, check your plug leads and caps and all the wiring and especially the switches for corrosion.
Instead of using a plug, go to your local auto parts store and get an ignition tester. they cost like $5 and are just an adjustable gap. use that in place of the plug. You put one end in the plug cap and clip the other side on the head fins. It should easily jump 1/4" or more in air. You can hear it as easily as see it.
Or just check that it sparks at the F/LF marks at around 5-10 degrees BTDC.
But it still sounds like a fuel problem. Are the bowls full of fuel and are the carbs new or "pre-loved"? How are they jetted? and who set them up?
What??? Iridium need resistor? I first time I hear that... I I should use normal plugs then..? I btw I think that my engine ground is the problem... I have none... I only grounded by the rectifire.
I set them and they are new. The jetting should be fine now... I was rich a little before? I think my problem is the engine ground... I I have none. Only grounded by the rectifire
The 'R' in the plug grade means it has a built in resistor
I was just wondering if you fitted NGK plug caps (which are also resistor, usually 5K/ohm) then fitted 'racing' plug wires (often resistor as well)
Your not using 30+ yr old plug caps?
The engine should ground fine through the mounting bolts, if you remembered to clean the paint off at least one of the mounting points?
The 'R' in the plug grade means it has a built in resistor
I was just wondering if you fitted NGK plug caps (which are also resistor, usually 5K/ohm) then fitted 'racing' plug wires (often resistor as well)
Your not using 30+ yr old plug caps?
The engine should ground fine through the mounting bolts, if you remembered to clean the paint off at least one of the mounting points?
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