Sheldon Brown said:Dave Thompson said:I agree with Sheldon about the Salsa Shaft, an absolutely superb
seat post. I will also add the Thomson Elite to the mix, very
strong. light than almost any carbon post and bulletproof.
Don't mean to diss your namesake, but the thing I don't like about the
Thompson is that it doesn't have any setback. Generally, I favor
seatposts that have a generous amount of setback.
Most frames are designed/fitted for a seatpost with some reasonable
setback, so for most riders, the Thompson Elite will give an
excessively forward saddle position.
I agree with this. I have a Thomson on one bike and a Syncros on the other. My
seat on both bikes is back as far as it will go. It works for me, but more
rearward range would be better. A no-setback post would be perfect if the
typical seat tube angle were shallower, but it isn't. Most bikes are still
73-74 degrees, and meant for posts with setback. As a result, more riders are
sitting too far forward than too far back, according to bike fitters and coaches
I've talked to.
Each design originates from a different manufacturing environment. The setback
comes from mass production with stamping and forging equipment, the no-setback
from boutique machine shops with lathes and mills. Neither is better or worse
if done well. The important thing is saddle position, and a good match between
rider, frame, and seatpost.
Matt O.