Convert SRAM Force 11 to single chainring I bought a bike with an SRAM Force 11 groupset a few years ago and my local bike guy says I'll have to replace the cassette soon. I only use the large chainring in front and that's apparently why I've worn the cassette so much with cross chain riding (if that's the term). 

He suggested converting it to a single chainring instead by simply removing the front shifter and changing the front ring and the cassette. Does that sound viable?

Thanks,

Torkil
I'd find a new local bike guy. Although the "evil of cross chaining" is a very persistent myth in the bike world, you might not be able to find any shop guy that doesn't preach this nonsense. 

All you really need is a new chain and cassette and a chain wear checking tool so you can replace your chain before it gets worn enough to destroy the cassette. If you replace the chain often and keep it clean, your cassette will last many thousands of kilometers. 

Switch to a single ring if you want, but doing so to "avoid cross-chaining wear" is complete nonsense. Seriously, do the math. Switching to a single ring crankset is going to move the chainring in about 3mm at best. The change in the widest chain angle is going to be 0.43 degrees assuming a 40cm chainstay.