Trek Wahoo rigid singlespeed 29er
I'm in the process of turning my 2012 into a rigid singlespeed thrasher and need some cheap cranks. Are there any suggestions for cranks? The stock crank is Shimano M171 units. Is it possible to remove the chainrings from it and just add a single ring? Also, is it necessary to use a chain tensioner considering the frame isn't SS specific?
No and Yes.
No, I looked up your crank and the pics I found look like it is all pressed/riveted together so the problem would be to change out rings that aren't meant to be. If you want to stay with square BB, crank arms are cheap and plentiful that allow being changed out (rings) or upgrade to a GXP, Isis, or Octalink BB.
And yes, if you don't have adjustable dropouts or an EBB (eccentric bottom bracket) you will need to run a tensioner (DMR, Surly, Rohloff, etc) or front mount like a Blackburn Stinger. OR you may be able to run a magic gear configuration, in which the right front ring and rear cog combo will net you a chain length tight enough to work, yet let you get a masterlink in. Check Sheldon Brown's calc-u-la-flucus-deal-ee-o. Go through the post up your SS thread because you will see alot of people's solutions to your very question regarding tensioners/magic gear configuration and see cool bike porn at the same time.
Have a great ride
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