The one in the picture is not threadless (i think, maybe im wrong,)
What are u looking for is an adjustable threadless stem, what i do not know is if your fork is 1 1/8 or 1 1/4 inches...
What i would do first is to put a shorter stem and get another seat, A road type of seat. Those buffy seats are pretty bad in my opinion because u have no support, too much padding or gel. People tend to buy them because the arss wont hurt?? but the thruth is that are pretty bad for the back and for pedaling. Its just like buying a sofa that has too much padding, so much that after a couple of hours seated watching TV your lower back hurts and u end up seated in the floor after wards
A good road seat will give you the support you need, the arss will hurt a little untill u get used to it (now you know why some saddles cost 20 bucks and other ones 300 bucks,) the saddle must be parallel to the floor, if the nose of the saddle is going down (your case) all the body weight will go forward to your shoulders and hands, probably thats why they hurt. U have to get a level tool for this.
Secondly, move the seat backwards a little bit, 1 inch or two if you can. That will make the ride softer.
Before spending more money just adjuts the seat, Saddle parallel to the ground and backwards one inch or two, lower the seat height half an inch also, if the seat goes back your legs will be more streched so you have to lower a little the seat height to keep everything sort of even. Go rding to test. If the problem still bothers you go to stage two, a new stem and stuff as you thought.
Last edited by ultraman6970; 08-22-08 at 09:12 PM.