Hi guys, we're trying to troubleshoot a problem on Greybeard's TW. It starting running rough and dying at stoplights when he was riding yesterday. We bought a new battery, checked and cleaned all the electrical connections, looked for air leaks, put in new fuel, and we're looking for other stuff to try...basically, the bike is a little hard to start, but we've got it idling well on the stand. Standing the bike up vertically will kill it instantly. Any ideas?