Bicycle Mechanics - Setback post forwards?

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sshock4
11-11-02, 05:43 PM
Can i turn around a setback post so that it is basically set forwards? Or will that mess up the goemetry too much?

Thanks


roadbuzz
11-11-02, 05:49 PM
Boy, it would for me. Whether you can do it or not depends on the post... there's a lot of variety.

The question in mind is 'what problem are you trying to solve?'

sshock4
11-11-02, 06:21 PM
There are two possible types, one being where it bends back then straightens again to take the same angle, and two ebing where it just bends. I am suspecting the former would work better.

The problem i am having is that i just bought a large Ellsworth Joker frame which is the right heigt for me, but a little too long feeling. I am going to get a very short dh stem but was wondering if i could also fix the problem with a setback post.

By the way is it possible to turn a stem backwards?


RacerX
11-11-02, 06:37 PM
The only people that do that is triatheletes. They flip setback posts around so that they can save their running muscles.
For any other type of riding, it will mess up your pedal stroke. Also, it puts so much weight on the front wheel that it is dangerous for anything other than time trials.

sshock4
11-11-02, 06:41 PM
Thanks. I was suspecting that it would mess something up but i wanted to make sure because i think there is a thompson setback on mtbr for sale.

greg360
11-12-02, 03:20 AM
ssshock4, I'm also looking to get a setback seatpost.
You might want to check out the reviews of that model Thompson seatpost from roadbikereview.com
http://www.roadbikereview.com/Seatposts/Thomson,Setback/PRD_28057_2510crx.aspx
From what the reviewers are saying, you can angle the post forward or aft, but get mixed results (depending on who you ask) either way.

Here's another seat post that with adjustable fwd/aft positioning
http://www.roadbikereview.com/Seatposts/Look,ErgoPost/PRD_28528_2510crx.aspx
The critics hate it, but you might find it suited for your situation.
It's too short for me (255mm), so I'm still looking for a post with fwd/aft adjustment and a longer (like 300mm?) stem.

Both posts can be had on EBay for about $80.

Anybody got any suggestions on other models/vendors?

roadbuzz
11-12-02, 10:44 AM
How much setback is there on the post you have? If there's much, reversing the post would probably be too much. Would a post w/little or no setback, e.g. something like this (http://www.performancebike.com/shop/large_photo.html?SKU=6446&Store=Bike), work?

Balance
11-14-02, 10:33 AM
Did you just ask if you can put your stem backwards? God, how much too long is that frame! While you physically could do it, it would take *some* getting used to. If you look at pictures of really old bikes and hobyyhorses, alot of them were setup like that. But it seems like there are many reasons to not do it. One issue would be front traction. When you stand you wouldn't be able to get as much weight over it. Think more front wheel washouts. I can't help but think it would affect the rake of the wheel. Or maybe that just has to do with the headtube and fork shape. Backwards stem... crazy talk. Try it!

Balance

Davet
11-14-02, 05:41 PM
One reason that you can't reverse a setback seatpost is that there will not be enough tilt adjustment to bring the seat back to level. The nose will be too high when you run out of adjustment.

uciflylow
01-05-03, 11:39 PM
I turned my seat post around Saturday because I just couldn't quite get my saddle far enough forward. It has just enough adjustment to get the saddle level and it feels great! The bike is a 56 cm most measurement systems recomended a 54 but the LBS suggested a 56. I noticed that I was having trouble with my achelies tendon hurting. I lowered the saddel and moved it as far forward as possible. I also realigned my shoe cleats. The saddle has very short rails and doesn't afford a lot of adjustments.

Did the larger frame cause the slight missalignment of saddle? Should I have gone with a 54 and used an even longer stem, I'm using 120 mm now,? Should I replace the post with one with no sit back? It also feels much better on my hands now and my knees are in a better position.

Greg
01-06-03, 07:39 AM
Originally posted by Davet
One reason that you can't reverse a setback seatpost is that there will not be enough tilt adjustment to bring the seat back to level. The nose will be too high when you run out of adjustment.

This was my first thought also. Mabey find one longer bolt?

Make sure the adusting bolts (as found on the Thompson) have a good amount of thread in the cylinder nuts. Wouldn't want it to break apart under load.