Seat Tilt Adjustment
 

Should be simple, right? Unfortunately it seems like the parts are welded together. I emailed Trek and even sent a pic of the seat postL

http://i41.photobucket.com/albums/e2...s/seatpost.jpg

The Trek guy told me the tilt is adjustable and it's just stuck. Boy, is it stuck! I took the seat off but the grooved parts won't come apart. I'm afraid to damage it and haven't had a chance to get to the LBS yet. Anyone seen a situation like this? Is the tilt actually adujstable or did the Trek rep mislead me? If so, any suggestions to coax the pieces apart without damage?

Have you tried loosening the vertical bolt? It's probably a 5 mm. Loosen it enough and you should be able to adjust the tilt.

Loosen the allen bolt. The metal plates may have gotten a bit "stuck" to each other, so after the allen bolt is loose, take your hand and slap the bottom of the saddle.

Getting a saddle "dead level" can be a bit tricky, because as you tighten the allen bolt, the saddle can shift a bit. Tighten slowly, and if the saddle goes off level, stop and level it again before fully tightening the bolt.

Maybe drip some Liquid Wrench in the grooves and lay the saddle on its side. Repeat a few times if necessary.

Check around, maybe a search in the forum, I think I have read that vinegar will dissolve oxidized aluminum. If that is the case just drip some between the parts then use a screw driver to carefully pry them a part. I don't think liquid wrench will work well since I don't think it acts on aluminum just steel.

We have a BINGO! Forget the ammonia and liquid wrench, this"ll do it.

Once you have loosened the allen bolt, and applied a lubricant I would not try to pry it apart with anything steel. You will scratch it up at best. If it requires some type of force other than hitting the seat with your hand, I would put a piece of wood against the top half and hit the wood (not to hard) with a hammer. If it still doesn't come apart pretty easily I would take off the seat, take the seat post out of the bike and clamp the top piece securely in a vice with the post pointing up and then using the block of wood against the bottom half hit it harder.

I'd take the seat post off the bike, take seat all the way off and smack the stubborn part with a wooden mallet. Hitting the seat will only make your hand sore. And a little dab of silicone grease on it when you put it back together will keep it from siezing up again.

Ive had that exact problem before. I used a hammer with a wide flathead screwdriver to get it off. Make sure to loosen the bolt, and place the screwdriver end against the grooved part.

Given how clean and new that looks I'd say that "cold forming" between
the steel screw and the aluminum "top piece" (for lack of a word) is very
unlikely. I'd bet that it is overtorqued and not lubed. My recommendation
is that old R&R song, "Twist and Shout".

If the seat can be removed, smack the stuck part with a rubber mallet or wooden mallet. It should come free. If that does not work, try something like WD-40 as a loosening agent. Then try again.

Thanks everyone, problem solved! I removed the seat, lubed the seams w/3-in-One, and used a 2x4 block and hammer. It took two good wacks but the pieces parted w/o damage. I hadn't tried that before because I was unfamiliar with this type of tilt adjustment and wondered if the grooves were "for show" (i.e. made cheap in china).

Is a bit of oil good enough before torquing back down? I have some bearing grease in the garage but is that overkill?

I meant to say to smear KY jelly all over it.

Steel and aluminum tend to sieze when in contact with each other. I would lube threads with a dab of grease and both sides of the grooved aluminum part. That way you will never ever have problems with them sticking together again. Plus it will be a lot easier on the threads when you torque everything back down.

You would!

I know I have a down on it but that "B" word appears to be on the Post.