2nd bad magnedo and cdi in a week

[happycheapskate]

How would using the killswitch "fry" the magneto or CDI? If its making a clear circuit, why would it do anything more than waste raw fuel spent through the exhaust?

 

[danlandberg]

If you use the white wire, it is supposed to put out 6-7v (according to the manual) Tell me what happens when you hook a wire on the + side of a motor cycle bat (6v) to a switch, and another wire to the - of the bat. to the switch. Now turn the switch on. What happens? fry the wire(s)! I know these things do not put out amps. But it is still bad for the mag! Do this over & over again, It IS going to hurt something!

 

[happycheapskate]

re: hurt something. I used to have a 5hp lawn mower engine (mower) with a horn button for a kill switch, wired to the coil (where the original stop switch was located), and grounded to the mounting bolt.

This worked really well till I layed a sweaty hand on it, and BUZZZZZZZZZZ. It felt like 110v household current. OUCH.

I used a regular toggle switch afterwards, and killed it from Hi Speed/WOT hundreds of times (commercial mower) and never had a problem.

 

[danlandberg]

That method does not work with the CDI ignition, I've tried it (Black to ground and Blue to ground) It will not kill the engine!

 

[happycheapskate]

This worked for me, either way. I am using the white wire for killswitch now, and also have an optional on/off headlight + tail light kit running off the white wire.

 

[danlandberg]

I don't use the optional method. I use the CDI Wires to kill switch method, Because the white wire is supposed to put out voltage! How many watts does your lights draw? And what volts do they have to have to work? It doesn't Affect performance when they are on? Where did you get the light kit from & how much $$ was it? That is my plan for the white wire!

 

[happycheapskate]

I got my light kit from Norman (real and screen name) on motorbicycling.com. $40.

You have to warm the engine up and rev it up pretty good before flicking the lights on, or you'll kill the engine. I use Walmart schwinn 3AA headlight as a extra/backup anyway, so I just take off and then flick the lights on at 20mph. Once its running, it runs fine, after tightening the spark plug gap a little and filing the plug strap a little like a popsicle stick shape.

 

[danlandberg]

So, it doesn't die at idle AFTER/WHEN the lights are on?

 

[dinoseer]

Check that tiny wire off the windings to the top arm...

Just a guess, but I bet that little tiny wire from the winding is breaking on you once you go for a long ride and the vibration of running the motor a long time breaks the end of the winding where it connects to the top arm of the magneto loop coil...see attached photo...

took another long ride today and the magneto went again!

wired blue to blue
black to black
white capped off
no kill switch

I have only gone on one successful long ride with my friend. I have done ok for many short rides. but when I try to ride all day I burn up a magneto. I have tried ordering from different suppliers. with no luck. never had this problem with any other motorized bike I have ever built. don,t know why it is happening. all connections have been soldered. and shrink rapped side cover has been sealed with silicone. just cant make this one reliable.

 

[Flapdoodle]

I gave up on a kill switch and just use the choke to kill the engine. There is a bonus doing that because the engine starts almost immediately with a rich gas/air charge in the crankcase.

On the to-do list is drilling a small hole in the choke lever for a line I can tie a metal ring to so I won't have to fumble for the choke lever. ~Bill