It sold for about $450 when new, and it wasn't that special even back then. If it's in perfect condition-maybe $100.
A Trek Bike.
You can find a replacement seat for your Trek bike at a local bike shop, online retailers such as Amazon or the Trek website, or through Trek authorized dealers.
Really hard to tell. They have pretty much the whole range from entry-level bikes to high-end race bikes.
To identify a Trek bike by its serial number, locate the serial number on the bike frame, typically found near the bottom bracket. Then, visit the Trek website or contact Trek customer service to verify the authenticity and details of the bike using the serial number.
It can cost anywhere from about $400 to $9,000.
The price of a Trek bike can vary depending on the model and features, but generally ranges from 400 to 12,000.
The thread size of the pedal on a Trek bike is typically 9/16 inches.
I'm assuming the 21 refers to the number of gears. If that's the one it was $300 as new, so at most it'll be $100 today.
trek
About £5 ($8.32)
A Trek Madone bike can be located at retailers such as CS West Bikes, Outside Outfitters, or Pro Bike Supply. If you prefer shopping online you can check out eBay and Amazon or online retailers such as Trek Bikes, Bicycling, or Wimbike.
You can find Trek mountain bikes near you at authorized Trek dealers, specialty bike shops, or on the Trek website.