I have a Trek 1100 road bike from 1994. A friend of mine wants to pedal the Great Allegheny Passage from Cumberland to Pittsburgh (150 miles on a railtrail). I have ridden this bike on our local rail trail. It goes ok, but handles poorly in the loose gravel. The fit is not optimal--I think a shorter stem would help. My neck aches during the ride and I don't have a comfortable hand position.

Option 1: See if I can get wider tires and adjust the stem on my existing Trek 1100. Any thoughts on how much this might cost? Is it worth it to upgrade the old bike?

Option 2: Buy a new bike designed more for the rail trail. I would have to buy a cheaper ride since I just bought a Madone last summer. I know, I know. Suggestions for this option? Local brands are Trek, Cannondale, and Specialized. I would also use this bike around here on rides with my son.

Option 3: Don't spend money, just suck it up and deal with my current ride.

Option 4: 150 miles is too far. Stay home and mow the lawn instead.

Thoughts?