Spark, Fuel, but no start!

[dustn]

I’ve searched but can’t find a similar post. I got this 77 650 for $200 with no title and no start brought it home gave it power to the coils and it started right up! Since that first start I pulled the motor out to cut tabs off the frame and rewire everything since most everything was new. I have mikes pma and capacitor so kick start only. I have spark. I have fuel into the carbs (bs38) newly rebuilt with lager mains 135s since I’m going with pods and open exhaust, but I don’t get fuel into the cylinders. Plugs are dry unless I pour gas into the holes and try to kick it. It’ll pop once or twice but won’t run. Stock points ignition. Really not sure what’s going on. I’ve spend hours messing with it and pulling the carbs off to check them and plugs to check spark a million times and still no starts. Just a few pops. Super frustrating. Someone please help or I’m going to burn this bike to the ground!!

 

[Jan_P]

Can it be that you are 180 degrees off on the spark ?
Piston is on top dead center ..with spark ... but the cylinder is on the exhaust stroke so the out valve is open
It was a while I had stock points. So I dont remember .But there perhaps can be a crossing of the wires.
The original petcock on tank has a position with open and another that needs underpressure to open
put it in the open Position was it Pri

 

[dustn]

I’ll try switching the coil wires around and look for a post about setting up the points. I’ve never messed with points so I really don’t know what I’m doing.

 

[Boog]

Hello Dustn and welcome from Virginia. If I read that correctly, you are not getting fuel to the cylinders? I see you have rebuilt the carbs and you are getting fuel there. I'm not sure why it isn't getting to the combustion area though. Something is blocked in there. Have you pulled the jets yet and made sure they are open?

 

[dustn]

Hello Dustn and welcome from Virginia. If I read that correctly, you are not getting fuel to the cylinders? I see you have rebuilt the carbs and you are getting fuel there. I'm not sure why it isn't getting to the combustion area though. Something is blocked in there. Have you pulled the jets yet and made sure they are open?

Jets are open. Nothing in the intakes but I’ll check again tomorrow just to double for the millionth time haha. Really just tired of kicking on it! Wish I had a good starter to just spin it over while I’m diagnosing this.

 

[Boog]

You could always rent a teenager couldn't you?

 

[Jan_P]

I’ll try switching the coil wires around and look for a post about setting up the points. I’ve never messed with points so I really don’t know what I’m doing.

Hello again
If the bike ran pre service .. The points will be at least in reasonable position.
So a little better than were we are at now should be reached
to the Coils according to my schematic for an 1980
for 2 coils there are 4 leads + 2 to plugs
to both a red white which is power supply
and one Orange and one Grey
If you change the Grey and Orange position. Switch those over
And try to start --- Post here what happens
It can be carburetor but the above is simpler to test first.
And in my view more likely. Be the cause.

 

[gggGary]

Id put a bsttery in the system for your start attempts. It'll make this a lot easier.

 

[dustn]

Id put a bsttery in the system for your start attempts. It'll make this a lot easier.

I’ve tried it with a battery too. Spark looks the same with or without it and the bike will be batteryless when it’s done so I’ve been trying to start it without it. No starter anyway just the ole electric leg.