I have a Trek 730, 1995, so I realize that it's a heavy bike. But for moderate paced paved road rides, which would provide the most improvement; better wheels, or smoother rolling tires. And which tires or wheels would you recommend ?

I wail keep the present wheels so as to run 38s for gravel.

Tires will be a better bang for the buck. I like compass tires but I would probably get paselas for that bike. They are almost as good and a lot less expensive. I would not spend a lot of money on wheels for that bike. The OEM wheels are fine unless there is something wrong with them.

I have a similar bike, Trek 730 1997. I would suggest for road that you go down to 28s with relatively low weight and smooth tread, but some flat protection. Vittoria Rubiono Pro III, Michelin Pro4 Endurance, and Gatorskins come to mind offhand.

You should try smooth tread tires with flat protection first.

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