Engine bog has me boggled

Hello all,

I need a little help with this one. I have a 1978 KZ1000 A2. All stock. When I drive normal it runs fine. When I roll the throttle on from 3000 rpm it starts to accelerate but then bogs down terrible. Its like it is not getting fuel. I am not sure what is causing this
Here is what I have done so far.

cleaned and checked petcock, new gas.
thoroughly cleaned and set the floats on the carbs.
set ignition timing and checked advance, Dyna pickups and coil system.
new NGK spark plugs.
new plug wires and caps.
carb to intake connectors look good.
new combo rectifier / regulator, works fine.
I haven't checked the valve clearances but they sound good.
I do not have the airbox connected, but that shouldn't cause this issue.

It was running rich and stumbling/backfiring on acceleration before I started to tune it to a leaner setting. Now it is leaner, no backfire, but bogs down.

any thoughts on this one?

thanks,
Ron.

3k rpm is about where main jet becomes active. Did you clean the jets and passages when setting the floats?

Warren3200gt wrote: 3k rpm is about where main jet becomes active. Did you clean the jets and passages when setting the floats?

I took out the jet sand their tubes, I will have a look at the passageway a bit better.

thanks,
Ron.

By the way, you cannot hear valve clearance. As they tighten up, they get less noisy until a valve seat burns.

Check your valves.
Steve

The mains are clear.
I am checking the valve clearances

thanks, guys,

Could you tell me the valve clearances for intake and exhaust?

The book says between 0.05 and 0.10 mm, is this for intake and exhaust?

thanks,
Ron.

Both in and exhaust valves, i would prefer the upper 0,10 mm.

update:
The carbs are as near perfect as can be.
The valve clearance is within spec from .07 to .08, good to go.

My friend Rolf and I were working through the issue and think it is the Dyna pickups. Its seems like an ignition problem. There is nothing left.
Coils tested good.
We did a rudamentary test on the Dyna but I can't find any "how to" documents on it.
Does anyone know how to test the Dyna pickups?
I don't know the model number of the Dyna pickups. Can anyone identify it?

here's a couple of pictures...

thank you for all your help. It is appreciated.

Ron.

What is voltage at the coil primaries vs. battery voltage? Voltage drop across the ignition switch can be significant.


Good Ridin'
slmjim & Z1BEBE

slmjim+Z1BEBE wrote: What is voltage at the coil primaries vs. battery voltage? Voltage drop across the ignition switch can be significant.


Good Ridin'
slmjim & Z1BEBE

the voltage was 11.6v at the coils and 12.8 at the battery.

I have a Dyna DS2-1 self contained ignition system. Pretty slim on the availability of troubleshooting guides . I am tempted to buy an new one from Z1E and see how it goes, but that would be a 200 dollar guessing game. The bike sat in storage without a points cover for years, Also the bike was dumped on this side as I can see road rash on the muffler pipe and rear brake lever and it was missing the points cover. Maybe this thing is done for. I can't see what else it would be but this. The symptom is weird and like nothing I have seen before, which is why I am suspect of the pickups. It runs beautiful up to 3000 rpm or so but when you apply more throttle to go the whole engine goes blah, no stumble just a gag effect.

bizzare.

any thoughts?

cheers,
Ron