Trying to start for the first time .. fires but wont stay running??

[Luke4554]

Ive got gas .. ive got spark. The bike will fire for a sec like sputter pop and keep cranking. We cant get it to stay running. Also weve been working on it for like 30 min and now my coils are super hot.. is this normal? i assume yes. Im getting annoyed.. its so close but it just wont go .. any ideas? I thought maybe i had my coils hooked up backwards but after shifting them side to side we couldnt get it to fire at all.. so i assume it was right.

HELP .. SHIT!!

Luke

 

[5twins]

So I take it you still have points? If you leave the key on and a set of points is closed, your coil for that set will keep charging up and get hot. It releases that charge when the points open but since the motor isn't being turned over to do that, the charge keeps building. It's not a good idea to leave the key on for too long or you can burn a coil out.

It sounds like your timing and/or points gaps are off.

 

[Luke4554]

how do i go about fixing this .. i have the bike rewired and im not sure if i have something wired up incorrectly or what. Right now the coils seem like theyre getting 12v as soon as i turn switch + on

 

[Luke4554]

And what do you mean about having the key on too long? How do you set the power source to feed the coils without being on when you turn on the key? .. im so confused.

 

[5twins]

I wouldn't let it sit with the key on for more than 10 or 15 minutes at a time. Turn the key on, do whatever (set/check timing, troubleshoot electrics), then turn it off. In other words, don't let the bike sit for hours at a time with the key on and not running - you'll burn a coil out for sure.

There's nothing to fix really, this is how points systems work. As long as you're aware of the fact and don't leave the key on with the bike not running for extended periods of time, everything will be fine.

 

[Luke4554]

ok well i suppose ill play around with it some more and see if i cant get it to fire

 

[5twins]

Like I said, it sounds like the timing is off. With everything set right, these are easy starting bikes, like one kick many times. Did you have the advance rod out or the ATU apart for cleaning? If so, that stuff can be installed incorrectly and put your timing 180° off.

 

[Luke4554]

It sounds like your timing and/or points gaps are off.

how do i set/check this?

 

[Luke4554]

also my electric start will crank the bike fine until you give it gas or it starts to fire then it seems like it slips. ill be cranking it .. give it some gas and the starter will let loose like its not meshed in gear anymore. does this make sense to anyone? .. i dont get it.. it seems to do it when the motor fires too sometimes. it will crank fine then all the sudden spin out real high like the gears came un meshed

 

[Luke4554]

Like I said, it sounds like the timing is off. With everything set right, these are easy starting bikes, like one kick many times. Did you have the advance rod out or the ATU apart for cleaning? If so, that stuff can be installed incorrectly and put your timing 180° off.

no i didnt have any of that out or apart. For the most part i just pulled the motor and put it back in. it was sort of hard to start originally .. but it would at least run

 

[yamabob83]

maybe the specs of the rotary on the inline are out of spec? My 2 cents

 

[Luke4554]

it RUNS!!!!! .. it was the yellow wire on the alternator.. clipped it and it fired instantly. thanks for the help guys

 

[XSLeo]

The yellow wire from the alternator goes up to the safety relay. The safety relay stops the starter from cranking after the engine starts. It also stops the starter from cranking while the engine is running.
As you crank the starter and it starts the alternator starts to produce electricity, it sends voltage on the yellow wire to the safety relay. When the voltage reachs 2.5 volts, the relay opens the contacts and stops the starter.
If your safety relay is working at to low a voltage, say one volt, it will trip the relay at cranking speed. Cutting out the starter before the engine starts.
So when you clipped the yellow wire you disabled the safety relay. It will work just fine that way. Just be carefull not to press the start button when the engine is running, and release it as soon as the engine starts.
Holding the start button to long will over run the gears and do them damage. It may take a while before the damage gets bad enough to be a problem. Pressing the start button while the engine is running will do pretty much the same to the gears.

 

[XSLeo]

OOps don't need two.