Want more top end/mid on 96 yz125

I think i need just a little bit more top end on my bike. The other bikes especially 4 strokes are easily pulling me on the straights. I was told I was first out of the gate, but i wasnt first going into the corner. Last weekend at my race we had lots of hills and it was kind of slick, given that my back tire is shot and i was sliding all over the place, the tire is first on my list.

The bike has PC pipes and boyeson reeds, 12/50 gearing. It seems to be jetted properly (i still get some spooge though) last time i checked my plug after a race it was brown, but i putted back to the truck so im guessing with the little extra build up it should be about right.

Is it the gearing? I ride with a couple of guys who were jumping this uphill double and one was clearing it in 4th and the other in 3rd. I hit it pinned in 4th and cased it every time, i triied 5th, tried seat bouncing, and just couldnt get over the thing. The one hitting it in 4th has a 6 speed like me. Do i need to add a tooth to the front, or spend the $$$ and get a vforce or porting?

nitro - they are boyeson power reeds i believe.

whyzee - i think i will try the 13t sprocket, i just bought new sunstar sprockets and a did chain. The chain is holdiing up fine, but i have heard 12t or less is bad for them. My bike has quite a bit of bottom end, it suprised me when i bought it because it pulled so hard all the way through the powerband, but it gives up a little at the very top. I usually hit the jumps and take corners in a gear higher than most of my riding buddies, because it will pull a gear higher with a little clutch, but it seems like they can always get me in the wfo parts like hills or straights.