Sudden loss of power

After 6mo of being pissed off and busy I'm back on the kz project. This spring I spent a lot of doh trying to get the beast working with limited luck.
After one 250km ride I started having sudden loss of power issues similar to a fried Dyna coil. After about 10 min of riding the bike would bog down and stall. After about 5-10 min of sitting it would fire up fine and then I'd ride home but it seemed like the power was weak a bit. My thought are electrical or fuel. I have replaced the entire electrical system other the wire harness . I did install a new single feed peacock and added a t joint to feed both carbs
It is winter here in Canada so now is the time to tinker

Make sure the fuel line does not have any kinks in it. Ed

Check the vent in the gas tank cap, as they have been known to get clogged.

Would also flush the fuel tank (remove tank; add some fresh gasoline; shake it around; and fast dump through filler hole).

And remove the petcock from the fuel tank, and clean the petcock screens that fit up inside the tank.

Also clean the petcock sediment bowl, and filter screen.

Good Fortune!

Tank -> Clear tube in-line fuel filter -> carbies... Gas flowing?

"I did install a new single feed peacock and added a t joint to feed both carbs"..
Pingel or cheap knock off such as Bikers choice petcock?
Did this same issue occur with original petcock?

"I have replaced the entire electrical system other the wire harness" Stock ignition components (points/condenser) or Dyna series/other E.I?

NOTE: I realize you mentioned Dyna coils but not the ignition pickups so just asking...

If Dyna ignition, good engine case ground?
Ideal +12Vdc (battery) to ignition plate?
Ideal pickup leads to coil terminations?
Coil leads not shorting to frame (ground)?

Just some thoughts....

OMR

Sounds like crud hitting a main jet.

So it is finally warm enough to work in my crummy shed and I'm back looking for the issue. Good news I can replicate the issue in the shed.
after about 10-15mins bike starts to die if you apply throttle it stalls, I tried putting on the choke progressively to see if I could keep it idling but it eventually stalls with full choke.

"Tank -> Clear tube in-line fuel filter -> carbies... Gas flowing?"

I did fix a kink in my fuel line. My petcock is new from z1 and I didn't have any issues with the old one, the seals are toast on it so can't try it.

"
NOTE: I realize you mentioned Dyna coils but not the ignition pickups so just asking...


I have dyna coils and ignition.

one thing that was added was an acewell tack/speedo that wraps around the ignition coil to read the RPM.

oh I tried popping the fuel cap no changes

It does not sound like a fuel issue to me. More like a heat induced electrical issue esp if you let it cool off it will run again. Check the coils, maybe remove the tac and see if the issue goes away.

Which dyna system and coils are you running? The S or the III?

Yes when it cools it will start and run again for about 10 mins but sluggish.

I have Dyna S

I'm slowly going through all the wires and coils to see it that may be the issue.

I am suspicious of the acewell tach cord and thinking about it now it started after I added it. Is it possible that the wire could oveloading the coil?

I do not know if the tach wire could create an issue or not. But one way to check is to remove it and see if it makes a difference. I am not familiar with how it works or how it wraps around the coil, but maybe the coil can not cool off as well with it wrapped on it. But I do think that coils that are beginning to have issues tend to show them more when hot than when cool.

If not already done, would assure valve clearances are within specs.

Good Fortune!