Just ordered a 27.5 Fantom DS Sport for my girlfriend. I've been wanting a Motobecane for a long time, and when she told me she wanted a mtb, it gave me the chance to buy one. Actually, I did shop around quite a bit for an entry level bike. I couldn't find any decent used ones (in her size) locally, and even though I get discounts on Marin and Diamondback, none of their entry level offerings were really that upgradeable IMHO. I ordered this Motobecane from BD's sister site Bike Island (for $450). She's a novice rider, so I figured it would be a decent bike that we could upgrade.

I figure she'll ride the bike stock for a while, but I'd like to go ahead and get an idea of how to tackle upgrades. The main upgrades that I see would be:

  1. the rear shock,
  2. converting the drivetrain to a 1x
  3. replacing the coil fork

I've got some questions about each of these upgrades so bear with me.

Rear shock: I've got no experience with that coil rear shock (no idea how to even adjust one) but I figure it's probably bad. Specs say it's 190mm eye-to-eye. I'm thinking of one of those inexpensive DNM air shocks (~$80). One thing I don't know is if I'll have a problem with the bushings. Thoughts or insights?

Converting the drivetrain to 1x: I've never converted a bike to a 1x (although my bike is a 1x11), and this project is confusing. The stock cassette is an 8 speed, and that's not really ideal for a 1x conversion. The specs say that the rear hub is 8/9 speed compatible so I'm assuming that means I can't stick an 11 speed cassette on there? If that's the case, I suppose I'll have to buy a 9 speed cassette, derailleur, and shifter, right? I also figure I'll have to buy a 1x crankset, chainring, and change out the bottom bracket too. If I'm wrong, please correct me--and if you have any advice, I'm all ears.

Replacing the fork: Here's where things get weird. The stock Suntour SF15 XCM HLO fork appears to only be available with a straight tube, whereas the bike has a tapered headset. Can anybody explain how they've done that? Besides a new (air) fork, what else will I need to buy for this project?

From what I can tell, Motobecane uses this frame on a number of their models--this one being one of the cheaper options. I just want her to have a good experience, so if you have any suggestions on which upgrades would be a priority, please let me know.