I have a 97 banshee, I recently added FMF Fatty pipes and silencers, boost bottle, power reeds, and K&N filter. I do most of my riding at around 2500 feet above sea level. When the bike was stock it had 200 main jets in the carbs. after making the mods I put in 270 mains, since then I have worked my way down to 220s. I think its jetted ok. After running the machine at 3/4 to full throttle for about 1/2 a mile the plugs are a grey - tan colour, the electrode turns black at the bend. I think the grey colour comes from the synthetic pre mix oil that I use (Belray MC1 @ 45:1) The power increase is really good but I have a dead spot at the 1/4 - 1/3 throttle position just before the power band takes off. The bike splutters a little at this point but it clears its self as soon as the throttle position is increased. I have spent a great deal of time adjusting the main jets and needle position. before I start changing the pilot jets to try yo correct the problem I though I shouls see if anyone else has worked on this sort of problem? Is it typical? am i expecting to much from my machine. I want smooth throttle response from the low end through to the top.

Dave.