my rig is a 58cm, and measures 58cm top tube, center to center with fairly standard 73.5 degree angle. i have an all ultegra set-up. my silver ultegra seatpost weighs ~300gm's. anyone have any experience with a thompson setback? will it give me more options?

also, stupid question. with my present set-up if i put my seat all the way back on its rails it tilts downward a bit. am i missing the obvious here?

I think the rails are designed that way..I no when I put my saddle on a flat surface, it tilts downward. I can rotate my seat up and down on my seat post though, so the farther back I put my seat, the more I have to rotate my seat up..It seems like most seat posts have this function, I don't know about Ultegra off the top of my head though.

The Thompson seat post is highly regarded. I may swap out my carbon seat post for one.

I have put Thompson's on every bike I own. I don't thing you can get a better post. They are loaded with adjustments unlike those that use grooves for adjustment. Once you have it dialed in they stay put.
Fubar get the Thompson and try putting a seat on with carbon rails. Thats what I use and its amazing how it soaks up the road buzz.

Hi,
my wife and Sis have Thompson seat posts;they are light and nicely made. My Sis has a bike that's a little large for her; and the seatpost places her knee right where it should be. My wife said she felt a little cramped on the bike; so I put her old one back on.
If you can use the Thompson Setback, that would likely keep the knee over the pedal. If you're happy with the fit of the bike from the waist down; the regular Thompson is likely to bring you too far forward.
I mention t all this because you have the seat back already. You might want to look at posts that allow you to move the seat back more; like the Raceface XYZ. There is a post that comes on (I think) Masi bikes that is light, cheap, and has almost as much setback as the XYZ.

Would someone please explain the purpose of the Thompson setback seatpost. I did a little searching on Google and see what they look like but I don't understand why you'd want/need one of these over the standard (straight?) seatpost. It seems to me that you'd only need one of these if you can't achieve the proper kneed to pedal positioning - is that correct?

fubar5: Other than weight what benefits have you gotten out of your carbon seatpost?

Zack

To achieve a comfortable and efficient riding position, which may or may not have as much to do with "knee over pedal" as some would advocate. Rather than trying to explain, just read Peter Jon White's article on bicycle fitting relative to fore-aft position and KOP -- about 1/2 way down the page:
https://www.peterwhitecycles.com/fitting.htm

Thomson makes excellent products: we use their seatposts & stem on our off-road tandem.

Ti and carbon seat posts absorb certain types of road vibration and shock quite nicely compared to their Aluminum counterparts and have the benefit of being incredibly light with an infinite amount of fatigue life.

the setback seatpost is especially appreciated
with a saddle such as Brooks which has less
usable rail compared to most plastic shelled saddles.

Marty

Not really sure to be honest..It looks really cool!!

I know carbon is supposed to help soak up road buzz, and on that note, I can say that it( my carbon seatpost) must do a good job, because I haven't noticed the rough ride Aluminum is supposed to deliver. However, I also have a seat with Ti rails, so that may make a difference also.

I didn't buy a carbon post aftermarket, it came on the bike, so I don't think it's a really high quality post, or lighter than any other post. Either way, I ride in fear that the thing is going to break, so I'd rather switch to a Thompson. My fear may not be justified, becaus after all, my fork is carbon...But still, I would ride a little more confident a different seat post.

Just check some weights, a Thompson is actually a few grams lighter than what I have...Hmm. I'm going to go see what I can get one for at my shop.


How much is the post you're looking at RiphRaph?

I bought an Easton EC70 post in order to get the seat back a little more and it made a lot of difference in how the bike felt. It was the last tweak I needed to get the fit perfect. Are you talking about the Thompsons that are bent back, or the ones with the setback clamps?

the thompson is 180gm's and $80-$85 and the thompson setback is also 180gm's and is like $95.

Am riding with both Thomson seat posts and stem's on my road and MTB. They are the best thing since sliced bread, IMHO. Highest of quality. I really like the adjustments on them. Can easily move the saddle a very small amount. I ride with a Prolink saddle, which has some sort of suspension built into the rail system. And must say that it was a REAL improvement over anything else I've ridden. I don't use the setback seatpost as I prefer to be more forward on my bike. Short arms and short legs, I guess.

Cupla days ago I replaced a USE suspension seat-post (that came with my Sirrus hybrid) with a Thompson setback seat-post, because my bike was a skosh small for me and I wanted to peddle with the cranks located a bit more forward relative to my body. Some observations with the setback post:
*An immediate increase in average speed; at least 1/2 mph better than my usual average on a 20 mile ride. I wonder how much pedaling energy was being absorbed by the old post, instead of transmitting to the wheels.
*No noticeable increase in road buzz. In fact no change at all. I do have a nice Terry seat on board, though.
*A significant improvement in tactile feel for the road. With the Thompson, I soon was corning much faster and acquiring a confident feel for the bikes handling that just wasn't there beforehand. It's like I did not know what I was missing when I was on a suspension post.
*A welcome end to that annoying left-right pivoting movement that suspension posts make as you pedal.
All in all, it was a lotta bang for the buck (actually it was $47 on EBay) and I would recommend it to anybody wanting to make their hybrid a better street machine.

A 58 cm top tube is kind of long for a 58 cm seat tube. It would already place the saddle pretty far back.

The only bad thing about the Thomson setback is it is not as setback as other setback seatposts.

However, that all depends on personal preference when it comes to seat for/aft position. If you want a slight setback, then maybe its a good thing.