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extra long setback seatpost?

Hey all, I have a friend w/ some medical issues who recently acquired a tricycle type bike. Long story short, he needs to be sitting a little farther back in relation to the bottom bracket than the normal 20-30mm setback posts will allow.

Anyone know where I can find something like this in a 28.6 post?

Thanks!
John

Quote:

Originally Posted by john_iverson (Post 12095790)

Titec made the Hellbent with a 1.5" setback. You have to be careful, however because it put a lot of leverage on the seattube/toptube junction.

I happen to have one at home. Let me check the size and I'll get back to you.

Plain seat post in needed diameter, Kalloy makes them,
Brompton Saddle adapter pin and their Penta clip saddle clip.

SAP is horizontal when installed on a standard 7/8"OD top seat post,
the stepless, mostly aluminum,
180 degree adjustable clip, will hold the saddle over the horizontal tube .

Todd at Clever Cycles in Portland does this setback mod a lot for 'dutch bike' riding postures, on your typical UJB frame .

I agree , seat post insert depth cannot be too short.

My Hellbent is a 26.8. All the right numbers but in the wrong order. Sorry.

Thx for checking Mr. Cycco!

Fietsbob: We already have a "plain seat post" if what you are referring to is one of the low end jobs w/ a reduced diameter @ the top end to fit a separate clamp to mount the saddle. I'll check w/ Clever Cycles to see if this is a workable solution.
Thx much for the input!

John

use a 28.6mm to 27.2mm shim on the one at the bottom.

45mm setback
http://www.ambrosio.co.uk/ambrosio_seatposts.htm

Alternatives: velo orange grand cru, 32mm setback or nitto wayback from riv bike, +40mm.

there was also a ritchey 45mm setback seatpost, but that was only available in 31.6mm

yet another alternative is to find a specialized saddle your friend likes, because they have a lot of rail for adjustment.

Quote:

Originally Posted by AEO (Post 12097638)

I thought of suggesting a shim with my Titec post but rejected it upon further consideration. A long seatback post strains the seatpost collar and the seat tube/top tube junction. The Titec that I have broke a frame at that junction, even though the post has plenty of insertion. A shim would have to extend way down into the frame to avoid putting additional pressure on the junctions. It's best to have the properly sized post with this post

http://www.nexternal.com/icycles/images/hellbent.jpg

Quote:

Originally Posted by MrJames (Post 22482398)

Hello,

I am a former road bike rider.

I say old because I had lengthening surgery because of my obsession with short stature. (I would appreciate if you don't ask questions about this please)

My old height: 158 cm
My new height: 166 cm

Old inner leg length: 72 cm
New inner leg length: 80 cm

The operation was from the upper leg, that is, the femur.
An lengthening of +8 cm was made to the femur length.

It's a very exceptional situation, if I look at the frame size according to the length and inner leg length, it will probably be wrong because the upper body, arms, etc. short.

I wonder if it would be a fiasco if i took 50-51 size bike, you know, the arms are short.
I guess there is no solution for short arms in the big bike?

In summary, there is a situation where the femur is long but the arms are short.

If you could help with this situation, I would greatly appreciate it.

thanks

You would require a frame with short reach, enough stack height to suit your position at the bars, and a very long setback seapost installed.

https://99spokes.com/en-AU/compare?b...;*z.47cm|w.700

The old Marin Ravenna and Marin Argenta bikes in size 47cm would fit pretty good, with something like a 45mm-or-more setback seatpost.
You can search around online and come across some very setback seaposts.

TiCycles could make you a seatpost of any setback and diameter. I have two 160mm setbacks in 27.2. Dave Levy is an engineer and machinist in addition to framebuilder. For his posts, he uses the excellent Thompson hardware so, like Thompsons, they are a joy to set up and dial in.

Quote:

Originally Posted by tangerineowl (Post 22483202)

After 11 years, I think the problem has been addressed.