Originally Posted by
CleanClassics
That's not out of the equation, but I don't know what the lineage is to find an equal bike.
In the car world an example would be Chevy made an S10 from the late 80s to the 2000s, but it was replaced afterwards with the Chevy Colorado and so if I was looking for a vehicle like an S10 after 2003 I would shop the Colorado.
If I could get pointers on what the lineage evolved to (I think the 400 stopped in late 80s / early 90s), I could figure out what used (or new) bikes to get.
Treks went from the three digit series to four digit series meaning aluminum, or then a four digit starting with a 2 meaning carbon fiber. They actually still made these around the same time. They then evolved to more higher numbered series and models like the Madone and Domane are now what they would call road models.
In short, Trek doesn't make a steel road frame like that Trek 400 anymore. They started phasing out steel road frames a while ago. They do still make a steel touring bike, but that's really not going to be anything like the 400 your dad liked. That would be a Trek 520, which is a good bike, just not exactly the same.
Like other posters mentioned, I will also suggest you look for another old Trek road bike (or just another brand vintage road bike in general), they aren't super expensive, they are easily available (I could look at my local craigslist right now and find 3-4 that are great picks) and they will be much closer to that Trek 400 than something new. That being said, if your dad is looking for a
new new bike, then he should probably just go to a local bike shop and test ride some. Window shopping is fun and all but he won't really be able to know what he likes by just looking online. He also may find that a more upright, commuter type bike actually better suited for what he likes to ride.
You also should remember, we are the Classic and Vintage forum, so we do know a lot about bikes, but we really like the older stuff for various reasons and aren't all that likely to say that the new bikes these days are all that comparable to the older stuff.