At 6' and tipping scale around 340 is the frame of the f7 able to stand up to twisting of my weight? I know the wheels will need to upgraded and as parts fail I replace them with higher quality parts. I like riding and now riding about 8 miles every other day 60/40 street/trail on a walmart special. It is time to get into a better frame as I continue dropping weight. I start at 370lbs four months ago but now the walmart bikes is start to fall apart. I like the feel of the f7 and priced around 600 so it in my range. I look at the f5 very nice looking but frame look more for speed than for toughness. Am I right? Thanks ahead for any advice and tips.