Your starter is definitely drawing too much voltage when hot. Agree with the others about the starter clean/rebuild etc.I doesn't matter where or how I ride. After it warms up good it barely turns over, After it has sit for a few hours and cools down it cranks fine. When it's cool the voltage never drops below 11, when its hot it drops to about 9.6. With the bike running it usually puts out around 14.3 above idle and 12.5 when you stop and have the brakes on.