[FiveThreeOh]

I've got a 2015 Trek Marlin 5. Due to not ever using my front derailleur, I'm curious about converting to a 1x drivetrain. What advice can yall lend? Can it be done? Has it been done?

Can I replace my 7 speed freewheel with a 9 speed freewheel, get a 9 speed rear derailleur, an applicable chain, and a single speed crankset?

Please don't reply with "just get a new bike." I don't want a new bike. Built > Bought.

 

[Cotharyus]

Well, it CAN be done. Whether or not you can do it with the specific back wheel you have is another question, and I don't have the answer to that question. But I do have another question for you.

Why not 10 or 11 speed? Especially if you have to do a new wheel...

 

[FiveThreeOh]

If I've gotta do a new wheel, then a ten or eleven speed is something I'd consider. Im shootin for a nine speed though, hoping that I won't have to replace the rear wheel.

 

[In2falling]

I've got a 2015 Trek Marlin 5. Due to not ever using my front derailleur, I'm curious about converting to a 1x drivetrain. What advice can yall lend? Can it be done? Has it been done?

Can I replace my 7 speed freewheel with a 9 speed freewheel, get a 9 speed rear derailleur, an applicable chain, and a single speed crankset?

Please don't reply with "just get a new bike." I don't want a new bike. Built > Bought.

9 speed and 10 speed are going away but Sram NX 11 speed should work.
https://www.sram.com/en/sram/mountain/series/nx?filters=&sort=Relevancy&page=1

Would need the following:
Trigger shiftier
Derailleur
Cassette (NX 11 speed is standard Shimano hub, and should work on ur wheel)
Chain

Up front for the cranks, would need to take off the 3 chain ring and replace with a single wide/narrow 32 104 BCD tooth ring.
https://www.oneupcomponents.com/products/narrow-wide-chainrings-104-bcd