Don't worry about the dialect,you can talk with the locals in Putong hua.Gejiu is a small city,but you can find many things are the same between the Kunming and it,including the gyms\ square\dance room,and so on.
If you want to buy a bike or travel by bike,i can give you a number.
0873-6807131.This is a professional bike shop in Gejiu,it calls"Gejiu zhi dian che hang(bike shop),such as mountain bike\highway vehicle.Also if you want to know any information about travel in Gejiu or the border areas,they can give you suggestion.
Gejiu is my hometown,when i was 2 years old,i moved to Kunming with my parents,but many relatives there.And i'm a mountain biker,so i have contacted the bike shop.
If you need more information, i think i can give you my cousin's number or email,he is a high school student.
Good luck.