I spent hours thinking this through this was the most comfortable thing I ever came across. I did set the seat a tad lower but not by much. It was a spring seat too. Then I found a super fat old man type exercise seat that looked almost comical it had springs as well. I set that seat even lower. Had to raise it back up.
I can run around on my touring peddle bikes all day long and it has no effect on me!!!!!!!!!
http://motorbicycling.com/attachments/f47/14908d1256281481-morini-time-full-sus-project-p1010008.jpg
Bicycling and Pain
Back
Back pain while cycling is usually caused by poor cycling posture. Good cycling posture is very different from good posture while sitting or standing. A posture that is comfortable for sitting still will not necessarily be comfortable while actually riding a bicycle. Correct cycling posture must facilitate the pedaling action, and also must enable the rider to cope with the jolts that result from road irregularities.
When riding a bicycle, the back should be arched, like a bridge, not drooping forward between the hips and the shoulders. If the back is properly arched, bumps will cause it to flex slightly in the direction of a bit more arch; this is harmless. If you ride swaybacked, bumps will cause the back to bow even farther in the forward direction, which can lead to severe lumbar pain.
Some back-pain sufferers modify their bicycles with extra-high handlebars so that they can sit bolt upright, with their spines straight. This is actually counterproductive in most cases, because a straight spine has no way to "give" when the bike hits bumps. Road irregularities will jam the vertebrae together, often aggravating existing back problems. The bolt-upright posture is comfortable if you're sitting stationary on the bike, but is not suitable for riding much faster than a brisk walk. Riders who for some reason require such a position should use some form of suspension...a sprung saddle at the very least.
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True Motorcycles are heavier making them absorb all the impact too. Every little nuance in the road is gone with them. Which was why I had suggested a different stance using legs to take some of the abuse.. One of the reasons why the bike I posted was so comfortable was because it was a heavy bike , shocks and huge tires. This thing was very smooth.
Motor cross racers get pretty tore up with heavy off roading too. They will look a little like they had been bull riding walking away sometimes. There bikes have a different stance as well taller.
A Honda Gold wing with some lumbar support now we are talking.
Or be a real out law biker dude and get a fat heavy set old lady to sit on the back to make my bike a smooth ride. Tell her to hold on tight to cause I would hate to have to turn around and go back to get her.