750 Ignition Problem/Stalls

I have a 750 seca engine that stalls out. i could keep it running if i hold the gas down above idle but once it drops below a certain point it just dies no puttering nothing help please ... i have a custom wiring harness but it has worked before .. engine has been sitting for a year i cleaned the carbs ect only problem i could see in the carbs is the bowl gasket catches the float a little could that be the problem... i also think it could be flooding because my spark plugs are black ... and i also though it could of been ground because it only sparks for a short amount of time.

 

"Hold the gas down above idle"
Forgive me but I'm not sure what you mean by this.
Wiring harness is a known good player...check
The float bowl gasket should not have any involvment in the float's travel range. It sits too high to be a factor. A slight interferance while installing the bowl is not uncommon. Wrong gasket perhaps? A gentle hand with a hobby knife should remove this worry. Easy does it and whittle a shaving or two off at a time.
Typically flooding leaves a wet spark plug, black indicates a rich mixture. Please review and clearify if you have fuel on the plug.
A loose/corroded ground is a possibility. At inital start up, the temperature is cool enough that the current can make it through but as the joint heats up, the current draw increases and develops more heat (known as a high-resistance joint) and the decending spiral begins. Check each ground connection and clean any that look at all dirty/corroded.
Another thought is that you have either a pickup coil going out, an ignition coil going out or a component issue in the TCI.
Check each and every component in your ignition system. SQLGuy published a step by step troubleshooting guide for your ignition system, look it up and use it.
Let us know what you find.

 

I cut away the Gasket and did the ground but now i dont even get a run at all i think i might of fouled the plugs. could you point towards the SQLGuy step by step guide thanks

 

Just to eliminate the easy, you have adjusted the idle screw as such that it maintains idle to 1100RPM while hot?

Holding the throttle open just moves the butterfly as there is no TPS on these bikes... So if holding the throttle open solves the issue then adjusting the idle screw is essentially the same thing...

This is assuming though that the point it dies is lower than 1100RPM...

Cheers
Dave

 

its not the idle screw it like its getting to much fuel or it has very weak spark that cuts off and on it would run then like after 10 sec it would just die no puttering nothing and it wouldnt start again unless i gave it gas or waited alittle bit ... i cant even get it started now even while pushing the gas

 

Typed Ignition Troubleshooting and SQLGuy into the search engine, here you go:http://xjbikes.com/Forums/viewtopic/t=21932/highlight=ignition+troubleshooting.html.
Go to it and let's see what happens.