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Trek Marlin 5 2021 upgrade 3x7 to 1x12 or 1x10

17K views 10 replies 7 participants last post by  mevnet  
#1 ·
Hey so I am relatively new to mountain biking and I just got the trek marlin 5 2021. I want to upgrade to a 1x10 or 1x12 and I had my eye on the Box three prime 9 groupset and I don't know if that will fit do you have any suggestions on what other options I might have.

Here is the Groupset
 
#2 ·
you'll need to buy a new crankset as well, because the crankset on the Marlin 5 appears to have the chainrings riveted together. that's most likely going to set you back another $100 plus labor if you don't have all the tools needed to remove the current crankset and bottom bracket and install a new one.

unsolicited advice: how long ago did you buy this bike? can you return it? upgrading anything on it is going to quickly become much more expensive than just buying a Marlin 7.
 
#6 ·
yes get the prime nine. I did have a problem with the clutch going out on my prime nine derailleur so spend the extra 30 and get the prime nine box two derailleur. it has a way better clutch and its way easier to adjust. Also the chain breaks about a month in. get the box two chain. The problem with doing a 12 or 11 speed shimano or sram is the hub driver. you need an xd or shimano micro spline freehub body to use the cassettes .
 
#8 ·
As others have said the cranks will be the hard part of the equation. Tool to remove your cranks is about $12 on Amazon. I have this one and I've removed several cranks and bottom brackets with it no problem. Not the bext bototm bracket tool I've ever used but it worked when I couldn't find my "good" one.


You can buy a square taper crank set for about $40-50 or buy another tool and switch to a hollowtech style crankset. Hollowtech will save you weight at the cost of less durability. Those square taper sealed bearing cranks are heavy but they seem to last forever..

Looks like the 2021 version of the Marlin 5 comes with a freehub not a freewheel so you are saved from having to buy a new wheel. You can double check this though by taking the rear wheel off, and looking at the center of the cassette. Do you see a large bearing or a 20 tooth splined lock ring. Lock ring will be a cassette and make upgrading easier.

Take a look at the Microshift Advent and Advent X drivetrains. I seem to read about more people having problems with Box than Microshift. I went with Microshift myself and did not regret it. 1x9 Advent with a 11-46 cassette can be had for less than $120 + chain. 1x10 Advent X in 11-48 range is $160 + chain.
 
#10 ·
As mentioned above you're going to be buying a lot of parts to make this bike good for the fun rough trails. It's designed for bike paths and smooth trails. It also needs an air fork, better brakes and wide rim wheels. List it for sale on Facebook Marketplace and get on the email restock list for this bike. wiggle.com | Vitus Nucleus 29 VRS Mountain Bike (2021) | Hard Tail Mountain Bikes Keep your bike if you are staying on bike paths.