eric gore, CR125 2000-04 134cc$500
You can only bore a 2004 to 134 as far as I know
Quote " I built my son a 134 (bore only). Had the head milled (actually material added then reshaped I think) to increase the compression, and had it ported. That along with the ovberbore really jacked up the compression. The compression increases on a 2stroke when you bore it. I also added a V-force reed, PC pipe and Barnett clutch. Let me tell you, this thing is fast. Really fast. My engine builder dyno'd the bike before building it, then after. He ran 3 passes after the mods and the last pass was the strongest, making 7.5 HP more HP than stock. My engine builder is reluctant to state how much HP an engine makes, because of wheel spin which reads out as clutch slip, and he says HP is relative, that's why he just showed me the amount of increase. If I was to do it again, I would stroke the engine as well."