A half-link isn't a universal panacea for singlespeed chain tension by any means. All it's letting you do is adjust the chain length by 1/2 an inch instead of the normal inch increments - you could fit one and find that your chain was still, for example, 1/4" too long. That equates to one hell of a lot of chain slop, far too much to use on a singlespeed anyway.
For example, something like only a .010" change of chainstay length (or .020" of chain length) affects chain "slop" by around 1/2" - and quarter of an inch change in chainstay length (or 1/2" chain length) will change chain slop by something like 8 inches (yes, really !)
These figures are based on "normal" SS chainring (32T/34T) and sprocket (16-20T) sizes BTW.
As far as tensioners go, the Surly works well especially in "push-up" configuration, but because it is spring loaded does allow some chain slapping around on bumpy downhills etc. I wouldn't rely on one to take up more than about 1/2" of vertical chain free play for this reason.
Another thing to consider is that any tensioner makes the wheel harder to get in and out of the frame - the nut on the QR fouls the arm on the Surly for example and with the Gusset you have to take the skewer out completely to remove the wheel.
So - your options if you don't want to do any frame modifications ( and don't get lucky with a magic ratio) are -
A sprung tensioner like the Surly ( quiet and nicely built), a fixed tensioner like the Gusset Bachelor (noisier, as it just has a plain polyurethane roller), the White Industries Eno hub (best option for rim brakes?) and the "Excentriker" eccentric BB converter. Both are about the same price (£120-ish) - with the hub you have to factor in the cost of the rim/spokes and wheelbuilding and with the Excentriker you need to budget for an external bearing BB crankset ( RaceFace, Shimano HT2) to use with this .
For example, something like only a .010" change of chainstay length (or .020" of chain length) affects chain "slop" by around 1/2" - and quarter of an inch change in chainstay length (or 1/2" chain length) will change chain slop by something like 8 inches (yes, really !)
These figures are based on "normal" SS chainring (32T/34T) and sprocket (16-20T) sizes BTW.
As far as tensioners go, the Surly works well especially in "push-up" configuration, but because it is spring loaded does allow some chain slapping around on bumpy downhills etc. I wouldn't rely on one to take up more than about 1/2" of vertical chain free play for this reason.
Another thing to consider is that any tensioner makes the wheel harder to get in and out of the frame - the nut on the QR fouls the arm on the Surly for example and with the Gusset you have to take the skewer out completely to remove the wheel.
So - your options if you don't want to do any frame modifications ( and don't get lucky with a magic ratio) are -
A sprung tensioner like the Surly ( quiet and nicely built), a fixed tensioner like the Gusset Bachelor (noisier, as it just has a plain polyurethane roller), the White Industries Eno hub (best option for rim brakes?) and the "Excentriker" eccentric BB converter. Both are about the same price (£120-ish) - with the hub you have to factor in the cost of the rim/spokes and wheelbuilding and with the Excentriker you need to budget for an external bearing BB crankset ( RaceFace, Shimano HT2) to use with this .
