My chariot, a 2004 C2 SX has a front end rumble nearly as raucous as a dragon with wind! Methinks perchance it may be a wheel bearing or driveshaft. It still happens in neutral so it is not an engine problem. The noise increases with roadspeed but decreases when the wheels are turned to either side. I have had my stable lad look and check nothing is chaffing (except his breeches!). Pray, do tell your view as to the cause and inform me how to deal with the matter lest I should have to resort to my palfrey. I live in Surrey so, if you know of a skilled but honest blacksmith please do tell pretty please nicely. With all gratitude, Elise