Help me slam my stem

Discuss light weight issues concerning road bikes & parts.
DJT21
Posts: 184
Joined: Sun Mar 27, 2011 7:35 pm

by DJT21

Not enough (or any) forward rotation of the pelvis. Stem way too short and too high. Bars pointing upwards. A fit nightmare basically.

You cannot get a good fit on a race bike without rotating forwards at the pelvis.

I would just buy a 130mm stem, slam it and adjust your bars so they're not pointing upwards. The bars will feel so far away that you'll have to rotate forward to be able to reach them, and that's your goal. Saddle will probably need to go down a bit (unless you have very flexible hamstrings)

DJT21
Posts: 184
Joined: Sun Mar 27, 2011 7:35 pm

by DJT21

You are riding it like it's a shopping bike

Image

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liam7020
Posts: 815
Joined: Tue Jul 27, 2010 10:04 am

by liam7020

Wookski wrote:Just slam and deal with it- Spacers are horrible


Horrendously stupid advice. Recipe for spending an extended period on the physio's bench.
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TheKaiser
Posts: 503
Joined: Thu Sep 05, 2013 3:29 pm

by TheKaiser

DJT21 wrote:Not enough (or any) forward rotation of the pelvis. Stem way too short and too high. Bars pointing upwards. A fit nightmare basically.

You cannot get a good fit on a race bike without rotating forwards at the pelvis.

I would just buy a 130mm stem, slam it and adjust your bars so they're not pointing upwards. The bars will feel so far away that you'll have to rotate forward to be able to reach them, and that's your goal. Saddle will probably need to go down a bit (unless you have very flexible hamstrings)


He may not have the biomechanics in place to allow him to assume the posture that you are prescribing. A lot of people who lack the hip mobility to ride with a very closed hip angle will just further round the lower back in order to reach a lower handlebar, and hunch the shoulders upward to handle the longer reach, so it is not a given that the rotation will occur at the pelvis with your setup suggestion. Similarly, he may/may not need a saddle adjustment, but as he rotates his pelvis forward to handle a longer/lower front end it will increase how acute the angle between his thigh and torso is at the top of the pedal stroke. If he lowers his staddle further, as you suggest, it will actually increase that angle further, which will stress the hip complex including the upper hamstrings more. It is unclear, when you mention hamstring flexibility, at which part of the pedal stroke you think that may be a limiter, but since they span 2 joints it is important to specify.

DJT21
Posts: 184
Joined: Sun Mar 27, 2011 7:35 pm

by DJT21

THe hamstrings will be the limiter at probably the 5 o clock position. If you think about rotating your pelvis forward, it raises your sit bones off the saddle and effectively makes your reach to the pedal a bit further. I guess TT riders overcome this by moving their saddles further forward (that also opens up the hips), but a road position is not as extreme as a TT position.

Something else that might make it more comfortable is dropping the nose of the saddle ever so slightly

Mep
Posts: 275
Joined: Fri May 28, 2004 4:11 pm

by Mep

antonioiglesius wrote:
Mep wrote:I have a long torso and tend to slouch so it makes sense that you guys are saying to straighten my back. Are we talking about lower or upper back though?

What I'm interpreting so far is to tilt the saddle angle down slightly (mine is perfectly level currently), rotate hips forward and try to bring up lower back to be more parallel to the ground.


Meld has an article on hip rotation https://medium.com/@meld3d/hip-rotation-5919de70a956, the pictures may be useful. For me, I think of it as pushing my stomach forward, so more of a lower back thing. Also, lowering stem impacts bike fit, so you may need to adjust say your stem length, saddle position etc. And because it impacts fit, it's best to do it a little at a time and have the body adjust gradually.

Amazing article, thank you for linking this. Makes a lot of sense, especially when I just hopped off a 2h trainer ride with my sitbones sore. Next week I'm going to try and tilt the saddle down till I can feel my sitbones lifting slightly off.

The idea of a longer stem is a little beyond me right now, even if it may well eventually be the right one.

Marin
Posts: 2764
Joined: Wed Jan 22, 2014 11:48 am
Location: Vienna Austria

by Marin

I like a few mm of spacers, I think slammed marks you out as a) a Fred with a too long head tube or b) a short guy

Marin
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Joined: Wed Jan 22, 2014 11:48 am
Location: Vienna Austria

by Marin

Degenkolb's bike for E3:

Image

darnellrm
Posts: 208
Joined: Thu Sep 10, 2009 1:06 pm
Location: NC, USA

by darnellrm

Yeah, but look how short that head tube is!! It can't be over 120mm

liam7020
Posts: 815
Joined: Tue Jul 27, 2010 10:04 am

by liam7020

Marin wrote:I like a few mm of spacers, I think slammed marks you out as a) a Fred with a too long head tube or b) a short guy


Completely
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"Sometimes you don't need a plan. You just need big balls." Tom Boonen

Fiery
Posts: 413
Joined: Sat Mar 16, 2013 9:21 am

by Fiery



So, did Degenkolb grow in height from his Giant-riding days, or was he a Fred back then?

Image

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Frankie - B
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by Frankie - B

Back to the original question, please.
'Tape was made to wrap your GF's gifts, NOT hold a freakin tire on.'

Mep
Posts: 275
Joined: Fri May 28, 2004 4:11 pm

by Mep

The result of lowering saddle angle by about 5 degrees was pretty significant. I'm starting to see how some folks think I actually need a longer stem. Weird.

http://picpaste.com/7ae937837916cb4ff04 ... ab647a.jpg

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bikerjulio
Posts: 1901
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

Do you have the saddle pushed forward? Kind of looks like it. Rather than looking stretched, you look cramped. And still very upright.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

Fiery
Posts: 413
Joined: Sat Mar 16, 2013 9:21 am

by Fiery

Tilting the saddle forward effectively lowers it. It now looks too low and too far forward - and the handlebar seems to be too high and too close relative to the saddle.

Tilting the saddle 5 degrees is a lot. Was it really that much nose up before?

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