Heavier bikes are less Prone.. my touring bike, with a load aboard, descends like driving a Coup D'Ville.
jyl says :
I have a bike currently that is un-rideable with hands off, in a particular speed range. The front and shakes, you have to grab the top tube, or the handlebars.
1 down 11 to go , get rid of the problem dont ride that one. sell it .