Please help upgraded bike not right


New Member
hello fellow e-bike riders. I bought a new Daymak Lonestar 72 volt. I got the shop to p it to an 84 -extra battery and a better controller. The problem im having is the bike sounds and rides like an old steam locomotive chug chugan along. I could fell this off the start and the faster i went it would disappear. another rider following me told me myback wheel was wobbling and i could feel the bike so the shop replaced the tire,there was a bulge. So now on the start it is smooth now but the wobbling and chugging now happens at 20-25 klms. Can anyone please suggest something i should be looking into.