You stated the Bike is extended... are 100% sure the extensions are square: Horizontally & Vertically
Most frontend problems originate at the rear and vise versa...
Also, check your swingarm's tightness and the bearing's at the Frame pivots.
Are those: extensions, or a modded swingarm, or a new swingarm
Did you reinstall the spacer's between the Frame Rails if you removed the Swingarm
BTW - This is in the wrong forum, it should be in MAXIMUM OVERDRIVE