Hi everyone,
I want to try out single speed, but I dont wanna spend a fortune. Would it be possible to remove the large and small chain rings from a truvativ fiveD crank and just run the middle ring? I know the bolts go through the large and middle ring together, so can I get shorter bolts? And will the system run oik with a 9spd chain?

My Truvativ single chainring crank came with a bashguard type protector in the outer ring position ad the inner ring bolt holes undrilled. It was exactly the same moulding as the triple.
Go ahead but watch your chainline and consider a chainkeeper to stop the flexible chain from bouncing off the ramped middle ring. Singlespeed rings are plain, unramped.

Without that outer bashguard, i,ll need shorter bolts though, right? Are they available?

Don't shift?

Oh, how I laughed, and laughed, and laughed! Phew.

Yes, shorter "single chainring" bolt are available. Also, you may have chain spilling problems as MichaelW mentioned since your current chainring is ramped and has special teeth to improve shifting, which is the last thing you want in a single ring set-up.

Changing it for an old type "flat" chainring is a worth while. Either find a NOS one at a older bike shop or Surly still offers them in a range of bolt circle diameters.

Thanks for the help guys. Anyone know where i can get those shorter chainring bolts?

Local bike shop. Especially one that sells BMX or single-speed/fixed gear bikes.