Re: Which way does a sprocket change affect the speedometer?
Yep that's about right. -1 in the front is a 6.25% change. Your speedo will say that you are going 6.25% faster than you are actually going. However most bikes are already off by a few % anyway so you might be as much as 10% off total, could even be worse than that.
Edit: if it was me, I would get the speedo healer.
If it has wheels, I've crashed it, and some things that don't razor scooter, skate board, roller skates, roller blades, skis, snowmobile, card board box on stairs, giant inner tube, nissan sentra, dirtbike, lawn tractor (wheelied it over), grandmas bread tray on stairs, kayak, canoe, rubber raft, bicycle, wake board, kneeboard, waterskis, tobaggan (plowed a pine tree), horses, ATV's