I have just got back from a 3 day 356 mile around the Yorkshire and Lancashire dales with three other chaps. Them on a 210, 200 and a 175cc. I'm on my 125 with a 150cc replacement cylinder etc. Generally I kept up, but I was lacking on top speed. Reved out at maximum 50mph. Also the hills of any duration left me slugging along. Do I need more cc or could i be clever with gear ratios and gain something? Currently it's a 1972, gtr 125cc gearbox.
Also we all got back safe and well with only myself breaking down with a throttle cable and the HT lead breaking down, but managed to bend it in such a way that it kept the contact to get me home.