I just purchased a Diamondback Outlook 07. I can't seem to get the seat tight enough to stay in position. It keeps sliding all the way down in the back which causes major discomfort. I keep tighening it but as soon as I hit a small bump in the trail the seat moves again. It won't go any tighter without stripping the bolts.
Has anyone else had this problem? What should I do?

Thanks for the help.

If it's the seatpost clamp you are talking about...I had this problem before....go pick up a seatpost clamp without a quick-release (I assume the Outlook still has a QR seatpost clamp...my old 2003 model did).

Most QR clamps don't compare to the clamping power of a properly made non-QR clamp. You should be able to go back to the bike shop you bought it from and get a really nice one for under $10. The best ones have a rotating threaded stud that the threaded part of the bolt goes into...this reduces stress on the bolt, which will allow for easier adjustment.

Before you run out and buy a new clamp, try rubbing dirt on the post. I don't remember where I herd this nor have I tried this but it is worth a shot...it's dirt cheap.

yea, and wipe a little bit of the grease off as well. it might be a little too slick for your clamp to hold.

It's both the seat post and the seat. The seat is the worst problem. The seat won't stay level. It keeps sliding all the way down in the back which brings up the front of the seat to a most uncomfortable position.
I have the bolts tightened as tight as they will go. They will stip if I try to tighten them any more.
As for the post it is a quick-release so it looks like I will be buying a seatpost with a clamp without the quick-release. But I still need a solution to the seat not staying in place.

Thanks for all the replies.

Check the seat clamp on the top of the post, make sure no grease is on the fine teeth in it. Also double-check it's assembly.

If this bike is brand new and acting this way, take it back to the shop you bought it at and let them deal with it. Seatposts are generally very reliable....so having seat clamp issues is odd, to say the least.

with the seatpost problem, if you can make the seatpost a little bit thicker it can help. You can put dirt, cheap (sticky) hair spray, piece of paper, tinfoil, etc... in there to make the tube grab it a little better. on one of my bikes i had a very creaky seatpost, it also slid down a bit even with the QR VERY tight. so i put some grease on the post, quite a bit of grease actually. this stopped the creaking and the sliding.

with the saddle clamp problem, in my experience, if it's just a little too loose and under a bump the saddle moves even one of those little notches, its all over. as the saddle starts to tilt backwards the screw gets more and more room to move, which means it gets easier and easier for it to move backwards.

in my experience, this can ruin a cheap seatpost, because your bodyweight grinds the little notches away until they don't grip as well. i was on a trail once and my polarized (or is it solarized?) sunglasses messed with the shadows, so i hit a large root i didn't see there, so my saddle took a lot of shock, and tilted back maybe 20 degrees. i got off the bike and noticed the clamp bolt was pretty loose, so i tightened it very very tight. it was ok for several bumps then did it again. after the second time the clamp was pretty useless, i could tighten it as hard as i could (and no dirt or grease in the clamp) and it would fall 90 degrees back just from trying to lightly sit on it.

i ended up getting a bontrager race (lite?) post with the clamp bolt out to the side, so I can adjust it easily on every ride without moving my saddle bag. so far i've had the post for about a year and it only did it once.