Acceleration just not quite there?

[yamtom]

more refined explanation

Hi Drum,
I will describe how this feels when riding the bike, keep in mind that this bike has some mods to it too, but jets are stock and the muffs do have some baffles but are louder than stock.

At idle, about one thousand to twelve hundred, a little bit ragged sounding with the clutch in, clutch out, smooth, then forward at a lineal feeling rate, very gentle and controllable, open throttle a bit and it just accelerates nicely, even with my big bones, very lineal feel, in other words, a bit more throttle give s a bit more proportionate acceleration, pretty much the same to 3k rpms, absolutely no stumble, no hesitation and no bog. At 3500 rpms, mufflers start woofing better, and bike surges , but lineal at a different rate to 5000, then its a roar and it shoots forward at yet a different increased lineal rate, obviously the needle is out of the main. Runs out of gas at 7000, obviously needs a bigger main. This is a thirty year old bike, I dont need to whack on it above five thousand at all, thats why Ive got the B12. If I want to scream around crazily, the B12 is the one to be on. Since your much lighter no doubt, you on your bike probably actually has a sense of being substantially faster than mine.

[dbeardslee]

Something to think about

The stock coils don't get their full voltage at low rpms due to the ballast resistor. The alternator doesn't put out it's full voltage until around 2.2k rpms - about where you were saying the 'lag' goes away. Additionally the stock coils only put out about 15kv, compared to 30kv on black Mikes XS or Dyna coils, or 45-75kv on Mikes green coils. And then there's the 30 year old high tension wires - unless you've grafted new ones in. If you want it to hammer harder, you might consider upgrading to hotter coils - it makes a big difference. With your jetting you're already packing more fuel/air mix into the cylinders. Put a good hot spark on it and I think you'll be surprised at the difference.

That being said, I've got to agree with what has already been said about the open exhaust - they're notoriously hard to tune to. A little back pressure is your friend.