1979 KZ650 ... major issues, please help!

Just an update...
I replaced the diaphragm and now it's working like a charm

Thanks for all the help!

Starting to have issues again

It revs fine in neutral, but when I put it into gear and ride it sputters and doesn't have much power.

I vac capped the petcock and carb again, and ran the petcock on Prime, but that didn't help.

Could it maybe be that the inline fuel filter is clogged? Seems like another issue where it's not getting enough fuel.

If not already done, would check for proper functioning of the advancer, which might possibly be stuck in the closed position and result in the reported symptoms.

Good Fortune! .

New fuel filter did not help

Patton wrote: If not already done, would check for proper functioning of the advancer, which might possibly be stuck in the closed position and result in the reported symptoms.

Good Fortune! .

Would that still let me rev in neutral, and only cause problems when in gear? Wouldn't it cause problems just revving in neutral too?

I feel like it might be a vacuum leak... it starts first kick every time and idles perfectly, just bogs down under load and gives the classic lean deceleration pops.

I sprayed carb cleaner around the carb boots and I noticed a change in RPMs... it actually killed the bike one of the times. I tightened the boots down as hard as I could, but that didn't help.
Time for new boots?

For anyone wondering, I replaced the points and condensers and it's running like new again