A friend just got his K0 engine back from a complete overhaul. It was converted to conventional valve springs, but retains the same rocker arm setup. Not sure if valve clearances would be any different.
It's only run about an hour.. and makes about 130 cold on each side. It starts easily, idles beautifully and sounds very healthy.
BUT, it stumbles about 6500 rpm in neutral, and loses power at about 5500 rpm under load. The plugs get sooty fast.
It had points.. and I thought that this was a symptom of ether low voltage, or a failing condenser. But the voltage is a nice 13.6 at the (dyna) coils. So i had a charlie's place ignition waiting to get installed.. so this seemed like a good time. After installing, the idle was even more rock steady, and it starts so easily you can practically blow on it and it fires. Still, falling on its face at higher rpm and fouling plugs.
Before the refresh, the motor ran great, but it didn't always. Those early CV kehins liked to send the slides up too quick so it would stumble in the midrange and darken plugs, but was great at WOT. I added springs to the slides and that problem was solved. handily. for years.
But I'm running out of ideas here. I jetted the mains down from 130 to 125 with zero change. Tried no springs, tried stiffer springs.. same story.
I'm willing to entertain anything, but I do not believe it to be an internal issue.
Thanks!
It's only run about an hour.. and makes about 130 cold on each side. It starts easily, idles beautifully and sounds very healthy.
BUT, it stumbles about 6500 rpm in neutral, and loses power at about 5500 rpm under load. The plugs get sooty fast.
It had points.. and I thought that this was a symptom of ether low voltage, or a failing condenser. But the voltage is a nice 13.6 at the (dyna) coils. So i had a charlie's place ignition waiting to get installed.. so this seemed like a good time. After installing, the idle was even more rock steady, and it starts so easily you can practically blow on it and it fires. Still, falling on its face at higher rpm and fouling plugs.
Before the refresh, the motor ran great, but it didn't always. Those early CV kehins liked to send the slides up too quick so it would stumble in the midrange and darken plugs, but was great at WOT. I added springs to the slides and that problem was solved. handily. for years.
But I'm running out of ideas here. I jetted the mains down from 130 to 125 with zero change. Tried no springs, tried stiffer springs.. same story.
I'm willing to entertain anything, but I do not believe it to be an internal issue.
Thanks!