Ok I may just go first then. Looking at both the TTR90 and the TTR110- The 90 has 12" wheels front and back, 3 gears, and a 624.8mm high seat. The 110 has a 14" wheel in front, 4 gears, and a 670.6" high seat. that's a 1.8" height difference. Both have the auto clutch and e-start.
Gavin is like 52" tall now? He's sketchy on that 50cc CRF, it's too small for him. Last time out he was in 3rd and WOT at times. I'm thinking 110 now, anyone?