Wt. on rear tire , 270 lb,s with me on it at 220 lb,s ,. = 362 lb,s rear tire capacity 617 lb,s,. that will leave 255 lb,s for the pile on, up to tire capacity,. as the pile on is over the rear tire,. my rear tire is a city grip,. front tire capacity is 520 lb,s power pure, your tires could be a little different,. my GVW. is 349 KG. = 769 lb,s