Has anyone ever used the DMR single speed conversion kit?? are they any good?

Christ, this takes me back.
I’m sure there’s many, many threads in the archive. And yes, they’re ok, but IIRC, there’s not much chain line adjustment, there are other adaptors with sets of rings of different thickness, allowing the chainline to be adjusted more accurately, and cogs with thicker bases used. It’s been years since I did a a SS conversion, things may have changed a bit.

This sort of thing works better, but is probably more expensive so depends how serious you are. On One ss sprocket (groove armada?) also has a 4mm base to it so won’t chew into your freewheel body. Spacers are Velo Solo IIRC.

IMAG0140 by Rick T., on Flickr

Yes i use a one on my old Kona explosif and it works perfectly fine

Holy Thread Resurrection, Batman!