Do you need chain tensioners on a road conversion with semi-vertical dropouts?

you don't need one but I have one on.

nope, my first conversion didn't have 'em, and it worked fine.

If you are going singlespeed w/ freewheel, then you could use a tensioner. But if you are going fixed, then you can't use any tensioners, they won't handle the stress of backpressure, and will fail terribly.

Semi-vertical might give you enough adjustment room. If you can move about 1/4" toward the BB, then you have enough adjustment space to make it work, though you may need to play around with gear combos and chain lengths to nail it. Perfectly vertical dropouts may require an eccentric hub (like the white ENO), or other tricks, like supporting a wheel soley on its skewer, filing the dropout back a bit, or using the so called 'magic' gear combos that match chain length perfectly to your axle/bottom bracket distance.

peace,
sam

Hmm, maybe there is confusion, do you mean a wheel tensioner like the tugnuts that pull the axle back and forth? Or do you mean a springy chain tensioner like the surly singlator that adds a pulley to pull on the chain?

peace,
sam

They were like Redline Chain Tensioners (like Surly's Tugnuts). The chap was riding a single speed. I was just wondering since I've never seen that before.

Use a rear derailleur. It does the same thing.

S/F,
CEYA!