OldWolf,
I put in the TBS needles with the goal of eliminating the "flat spot" in mid range acceleration. Goal accomplished. The dyno said I was a little rich through the mid range with TBS needles, where I had been very lean with stock needles. The extended tip of the TBS needles is mute because the head of the TBS needles laid flat on my plastic spacer under the spring. The lift will begin at the exact same time as with stock needles, but the TBS needles having more taper will allow more fuel earlier. The TBS needles extend into the jet farther but the taper at that point allows the same amount of fuel as the stock finishing nail. There was no difference in throttle response, but the midrange pulled much harder. Low end performance along with top end were unaffected. I think some will argue that the TBS needles are usless in our bikes. But, experience beats an argument every time - hands down.
Put in the TBS needles for a smoother power curve and drill your slide vacuum hole to 7/64" for a faster throttle response. You'll be smilin'.
