For some reason I CAN'T get the Grom up in 2nd gear. I can ride wheelies in first gear for days, but can't get it up in 2nd gear. My bike is stock, including stock gearing. Do I need to go down to a 14t sprocket in the front to get it up in second? I'm sick of doing wheelies at 10-15 MPH when I could be doing them at 25+MPH. Any suggestions?