0 setback? Or 90 mm stem? Which is less bad? [Archive]

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akelman

01-22-2011, 09:06 PM

slowandsteady

01-22-2011, 09:22 PM

You gotta get your leg position correct first (be it KOPS or otherwise) and then adjust your reach/stem (if possible).

ultraman6970

01-22-2011, 09:26 PM

I would move go with a smaller stem. Too long to explain because i dont know a lot of details.

Good luck.

ps: just notice... you again akelman? :P

AngryScientist

01-22-2011, 09:28 PM

oh boy, these are totally different, completely independent variables. first, set your seatpost fore/aft position, based on your required fore/aft position RELATIVE to the crank. then adjust your reach once you're in the proper seating position.

if this seems like an overly simplified answer, it is not, look at all the annexed fit references, there's a lot to understand...

Steve in SLO

01-22-2011, 09:28 PM

I'm with slowandsteady.
You might also take a look at weight distribution to come up with a solution, or use the 'Kirk method' of riding up a slight hill in an easy gear and see if you can lift your hands from the bars. If not your seat is too far forward (this is of course my simplified version).

allenwhy

01-22-2011, 09:33 PM

i use a zero setback post AND 90mm stem...

akelman

01-22-2011, 09:35 PM

i use a zero setback post AND 90mm stem...

And yet, the planet stills spins on its axis. How can this be?

akelman

01-22-2011, 09:36 PM

By the way, allenwhy, I wasn't making fun of you, so much as the widespread obsession with bike fit (I include myself among the obsessed, I hasten to add).

StellaBlue

01-22-2011, 10:02 PM

i use a zero setback post AND 90mm stem...

I run Zero setback and 90mm on all my rides.. I'm a midget

http://img442.imageshack.us/img442/4365/img0277zr.jpg (http://img442.imageshack.us/i/img0277zr.jpg/)

http://img406.imageshack.us/img406/8702/img0337yy.jpg (http://img406.imageshack.us/i/img0337yy.jpg/)

Why is either or both bad???

robin3mj

01-22-2011, 10:07 PM

I run Zero setback and 90mm on all my rides.. I'm a midget

Why is either or both bad???

Uhh...neither of the last 2 bikes are zero setback...

StellaBlue

01-22-2011, 10:12 PM

Uhh...neither of the last 2 bikes are zero setback...

My bad. I didn't realize I used a pic from before I swapped out the Most p-arts it came with..

http://img826.imageshack.us/img826/9272/dscn2912z.jpg (http://img826.imageshack.us/i/dscn2912z.jpg/)

W/ zero Masterpiece post

akelman

01-22-2011, 10:18 PM

Why is either or both bad???

I don't think either or both is/are necessarily bad. But it seems that most builders build their frames to be built with a 110-120 stem and a post with some setback. That said, as I noted in the OP, there almost certainly are too many variables -- including the size of the frame, not to mention the size of the rider -- at play for the question to elicit responses that are all that useful. Also, you have beautiful bikes.

Charles M

01-22-2011, 10:19 PM

We're done covering this...

My take away is that Colnago is pretty damn sweet

StellaBlue

01-22-2011, 10:27 PM

I don't think either or both is/are necessarily bad. But it seems that most builders build their frames to be built with a 110-120 stem and a post with some setback. That said, as I noted in the OP, there almost certainly are too many variables -- including the size of the frame, not to mention the size of the rider -- at play for the question to elicit responses that are all that useful. Also, you have beautiful bikes.

At my size (5'7) I would be way to stretched out at 120. And smaller frames are not an option from most builders.. I'm already at the low end.. : )

akelman

01-22-2011, 10:34 PM

I'm sorry, I can't read what you wrote. My monitor is covered with drool because I keep staring at your Colnago.

akelman

01-22-2011, 10:35 PM

Also, what's the rise on those 3T stems?

StellaBlue

01-22-2011, 10:37 PM

I'm sorry, I can't read what you wrote. My monitor is covered with drool because I keep staring at your Colnago.

Thanks.. I'm ashamed to say it gets neglected.. I ride the Peg 90% of the time.

StellaBlue

01-22-2011, 10:38 PM

84 degree

akelman

01-22-2011, 10:38 PM

I ride the Peg 90% of the time.

It's either a cult, or those bikes are some kind of awesome. Or both, I suppose.

akelman

01-22-2011, 10:39 PM

84 degree

Thanks.

allenwhy

01-22-2011, 10:41 PM

lol, is this an excuse to post pictures now? okay cool i'm game. :cool:
http://i91.photobucket.com/albums/k284/allenwhy/PICT1110.jpg
http://i91.photobucket.com/albums/k284/allenwhy/PICT1102.jpg

akelman

01-22-2011, 10:47 PM

Nice! I like what this thread has become.

A1CKot

01-22-2011, 11:33 PM

I like your kitchen.

Oh and you bikes too :).

oliver1850

01-22-2011, 11:56 PM

ultraman6970

01-23-2011, 01:18 AM

If the saddle tip plomb is in the same place with or w/o zero back seatpost, then there is no single difference in the pedaling or position. The plumb is the one that makes the differences, not the seat post. In the case of StellaBlue, the pinarello saddle plumb looks very close with both seatposts.

If you need to be closer do not buy a new seatpost, just move the saddle to the front whatever is needed. If you get short in the rails because you need to move the plumb even more, change the seatpost for a zero back one, but so far as long as you have travel in the rails to move it, all ok.

Now if aesthetics take some toll then that's another issue, with the seat plumb very close to the BB center a zero back looks better.

There are two extreme cases, giants and midgets (sorry cant find another way to say it ok? no bad intentions), giants are way back and midgets way close. Giants in fact use the seat all the way back, and sometimes they need more, then u need further seat back, midgets is just the opposite, saddle all the way to the front and they need be closer, get a zero back. But regular size people is kinda a waste of money to get a zero back seatpost because there is enough travel in the rails to adjust whatever u want to do all the time.

nites :)

jlwdm

01-23-2011, 07:19 AM

If you have one bike with the saddle in your correct position the plumb from the front of the saddle is a good way to replicate the position on a second bike as long as you use the same saddle, pedals and cranks. Changes in these other components can change the plumb measurement. I run three bikes with the same saddles, cranks and pedals at 11cm of setback.

But as said many times previously in this thread you need to get the saddle position correct to start. Then handlebar and stem options can be used to adjust the reach. If you can't get the reach you need the bike is not for you.

KOPS and blocking view of front hub with handlebar seemed to have been dispelled a long time ago.

Jeff

oldpotatoe

01-23-2011, 08:07 AM

If, in order to achieve your desired saddle-to-bar reach, you needed to run either a 90 mm stem or a zero setback post, which would you choose? In other words, which would you suppose would have the lesser (negative) impact on overall ride quality?

Without knowing all of the variables, there's no way answer this question, is there? But this is the Internet! So opine away! Really, I want to hear what people have to say.

The first, small 'c' constant is KOPS. Knee Over Pedal Spindle. Getting that correct along with seat height is the first step. That will be determined by a SB or no SB seatpost. THEN do the reach/stem.

Hawker

01-23-2011, 08:47 AM

I use a zero setback and 90mm stem as well and still am a bit stretched out.

My problem is a small size Giant TCR has a TT of about 52.5 to accommodate a range of sizes and I'm on the shorter end. The upside is that I have no toe overlap due to the longer TT. The downside is that the older I get the more my back hurts.

So...StellaBlue, sell me your Peg. :) And any chance you could provide the dimensions of all your bikes so the shorties here can learn and lust?

znfdl

01-23-2011, 08:59 AM

I don't think either or both is/are necessarily bad. But it seems that most builders build their frames to be built with a 110-120 stem and a post with some setback. That said, as I noted in the OP, there almost certainly are too many variables -- including the size of the frame, not to mention the size of the rider -- at play for the question to elicit responses that are all that useful. Also, you have beautiful bikes.

akelman, when Tom Kellog designed my bikes, he designed them around a 90mm stem. It all depends upon your body and weight distribution. I have found that both 0 and 14mm setback posts work.

PMP have really nice 14mm setback posts

StellaBlue

01-23-2011, 09:05 AM

So...StellaBlue, sell me your Peg. :) And any chance you could provide the dimensions of all your bikes so the shorties here can learn and lust?

Duende 48cm 51.5 TT
Master 50cm 51.5 TT
F3:13 48.5cm 53 TT ... A bit stretched out for my liking but I wasn't going w/ the 46cm...

BillyBear

01-23-2011, 10:16 AM

I'm sorry, I can't read what you wrote. My monitor is covered with drool because I keep staring at your Colnago.

+1

Geeeewiz

01-25-2011, 07:16 AM

Set back on the seatpost is not that big of a factor if you can still get the proper "saddle setback" in relation to the center of the BB. I think most would say that if you are running a 90 stem, the frame might be a bit big for you. Like most have said previously, get the setback first, then fudge with the stem. Good luck.

Marz

01-31-2011, 12:00 PM

Hi Stellablue. I'm 170cm, 5' 7" and I ride a 52 cm Pegoretti Marcelo, BB to top of saddle, 72.5cm, 110cm stem on a shallow bend Deda 215 (shorter reach than anatomic bend), and FSA 25mm setback post with saddle in the middle. I noticed your bike looks smaller, (51cm?) and I'm curious as to why we have the same height but such different set ups?

Love the Colnago, must be the polished lugs, shweeeeet.

rice rocket

01-31-2011, 12:09 PM

Depends on your inseam, femur length, etc.

I have long femurs so I have my saddle slammed all the way back as far as it can go w/ a 25mm setback post, and I run a dinky 90mm stem.

StellaBlue

01-31-2011, 02:43 PM