[BASSER]

imported post

The way I understand my manual, the pulse generators take care of the spark advance. When I twist my throttle more than about a quarter of turn, the bike starts bucking and I lose power, it doesn't backfire, it just acts like it is running out of gas.

I have,......................

changed fuel filter, flow tested the electric fuel pump, drained the tank, checked coil resistance and plug wires, replaced suspicious vacuum lines, changed the plugs, pulled the carbs and cleaned all jets, replaced fuel lines. Today my son and I checked the plug from the pulse generators and the book calls for a range of 1100 to 1300, when we checked each of the leads we are seeing right at 200. Because we are readinglower than the manual states, could that be my problem? Could I just not be advancing the spark enough. Earlier in a post someone told me to ignore the pulse generators that they either work or they don't, I'm beginning to think that is not the case? I hate to lay out the $80 if that is not the problem. I am almost to the end of troubleshooting and I have not found anything that I have done to make a difference in how the bike runs.

It will start quickly and throttle up with no problems in neutral. Idles perfectly, but when on the road, you get to third gear and rotate the throttle, it starts bucking and hesitating badly, I can keep it cranked and it will eventaully gain rpm, but it is not happy.

 

[retiredintime]

imported post

The pulse generators just tell the ignition circuit to fire, not when. That is determined by other means. I would think that your accelerator pump isn't working. What you describe is an engine attempting to increase it's rpm under load but not enough fuel to do it...

Or your vacuum slides are sticking...

 

[William_86]

imported post

the pulse generators only tell the ECU (engine control unit) the position of the crankshaft. the ECU is the one that will advance the timing in determinated gears so also check the gear sensor. if the pulse genetators were not working the bike would just not fire. right gurus?. i think it is a carb related problem. and if it was because it could not read when the crankshaft is spining rly fast it would even do it on neutral.

 

[rayworx]

imported post

The pulse generators are like any other 'coil of wire' in that they are effected by heat. Usually they will fail completely with no spark to the plugs. Other times they will operate when the engine is cold but malfunction as the engine heats up.
Disregard the resistance readings in the book. It's much more accurate to take an AC voltage reading.
Remove the plug coming from the pulse generator. Normally it's on the left side next to the battery. Anyway, on the lower plug (male side) connect your multimeter leads to the yellow and the yellow/white wires. Turn the meter knob to read low AC voltage. With the connector dis-connected turn on the key, with the engine stop switch in the ON position, push the starter button. While cranking you are looking for 0.1-0.3 ACvolts. Repeat the test with the blue and blue/white wires. This is the test they gave us at the Honda Tech School back in the 80's.