They are necked and 34 and a bit at the top, and 35 and a bit from the lower triple clamp down. pdxjim may be right. My friend's LC was highly modded, went, handled and stopped very well. There are several LCs 250 and 350, an R1Z, a couple of formula 3 TZRs and a TDR, along with 2x IT400, 2x IT 250, IT175, IT125, and an IT200. Oh, I forgot the CX125.