Help me build a 2x11 crankset with a 40t/42t big ring and bashguard I'm in the process of sourcing parts for a new MTB bike. The frame supports e-type top swing front derailleurs, and 92mm pressfit BBs.

And I want to have a 2x11 crankset with a 40t/42t big ring and 28t small ring, and a bashguard, because the resulting gear ratios fit my riding needs perfectly (I have an old bike with a 42x28 crankset and a 12-36 casette). Also, I want to avoid grease marks on my pants and legs, hence the bashguard.

I thought this would be easy, however it seems lately the industry has shifted to adopt either 1x setups or 2x with 24-34 to 28-38 cranksets that don't support bashguards. That doesn't really suit me, not only because of the missing bashguard support, but because the highest gear, 38x11, is just a tad smaller than my current 42x12, and I still have room for improvement.

What I'm considering ATM is


Build my own crankset sourced from parts on Aliexpress, because, although I find some chainrings on other online stores, I can't find a crank that supports bashguards. And Aliexpress is loaded with offerings, but I don't quite understand the specs, and I don't know how to check whether the specs of chainrings and cranks are going to be compatible both between one another, and the BB. So how do I build a compatible crankset?
Taking a cheap Alivio or lower-end crankset with a bashguard and remove the smallest chainring. I might end up with a 40t/30t crankset in that case, but that's acceptable. Are there trade-offs here, and if so, what are they?


I'm overwhelmingly inclined to go with 1., but still considering 2., and alternative solutions are welcome; I just want a Shimano-compatible 2x setup with a top gear greater than 42/12 and a bashguard.

BTW, I'm aware the front and rear derailleurs have capacities when it comes to min/max sizes of front chainrings and the difference between the smallest and biggest one; I've found compatible derailleurs.
Regarding removing a ring from an lower end triple crank. That won't work: the two rings you are left with will be biased toward the outside of the bike; the spacing of the rings on a 8 or 9 speed crank will be too wide to work well with an 11 speed chain.

You should check that you frame has chainstay clearance for larger rings. This can be a problem on newer bikes that are designed for small chainrings.

To select a crank that is compatible with your frame you need to consider two things, the bottom bracket standard and the chainline.

You say you have a frame that takes a 92mm pressfit BB, that's either a BB92 compatible with Shimano 24mm axles or a 392EVO compatible with 30mm axles. See here for a summary of BB standards. If you  have a 392EVO and you want a Shimano crank there are adapters to step down to 24mm axles, or manufacturers like Wheels Manufacturing sell BBs that adapt from a frame BB geometry to a crank BB geometry.

Chainline is connected to the rear hub spacing. Wider hubs require wider chainline. Manufacturers specs will tell you what chainline a crank provides and rear spacing (sometimes called OLD for over-locknut-distance) compatibility. As an example Shimano provides extensive and detailed specs. Here is the MTB cranks spec page.