1x9 or 1x8.
Currently running 36x11-28 9sp with the 28t cog trimmed out for better chainline (so it's really a 36x11-26 8sp). The chain was always dropping shifting out of the 28t, so I got fed up one day and made the derailleur never shift there again!
I have a Spot bash guard on the outside and a 3rd Eye Chain Watcher on the inside. I wouldn't mind getting some chainring spacers to make all 9 gears usable again, and also using two bash guards instead of the chain watcher.
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--Ben
2006 Trek SU100, 2009 Motobecane Fantom CX, 2011 Motobecane Fantom Cross Uno, and a Bakfiets
Previously: 2000 Trek 4500 (2000-2003), 2003 Novara Randonee (2003-2006), 2003 Giant Rainier (2003-2008), 2005 Xootr Swift (2005-2007), 2007 Nashbar 1x9 (2007-2011), 2011 Windsor Shetland (2011-2014), 2008 Citizen Folder (2015)
Non-Bike hardware: MX Linux / BunsenLabs Linux / Raspbian / Mac OS 10.6 / Android 7