The Bike Fitting Mega-Thread

@mcneese.chad, my copy of Dartfish is on a pc that’s just gone kaput otherwise, I’d mock it up and take a look. The changes in the video, to me, seem to be around the pelvis angle and neck.

Perhaps you can compare the two images when the right leg is horizontal at 3 o clock, by adding a vertical line down from the front of the knee to consider KOPS. Not because it will show right or wrong but because it will highlight a fore and aft shift relative to the pedal axle. Also, a line straight along the seat tube from the bottom bracket to see if it bisects the greater trochanter. Again this will highlight any fore and aft shift.

Another consideration @mvisio might be whether you have any perceived increase in weight/pressure in the hands?

Rotating hips is interesting. If someone is having to be ‘taught’ how to do this and thus holding themselves in an unnatural position won’t this lead to muscles being used for postural stability rather than phasically driving and thus reduce performance?

Here is a screen shot of KOPS with some lines to hopefully highlight any fore/aft changes. I think I’m slightly further forward with my current setup vs. original. I do feel slightly more pressure on hands, which would support that.

I’ll try bumping my seat back 5mm and attempt to roll my hips forward tonight. I just hopped on the bike and felt like my seat would need to come up for me to be able to roll my hips forward. With my hips forward at the current seat height, I dont feel flexible enough (almost as if my knees are crowded out by my body if that makes any sense)….So I may also adjust my seat upward as well.

Will post a new clip this evening, with hopeful positive results!

Thanks again everyone

1 Like
  • That can be the source, but you also dropped the bars which is the more common reason to feel more weight on your hands.

Alright everyone. Since moving my seat up also moves it back a hair, the only change I made in this fit iteration (dubbed fit #3) was:

  • Seat raised 7mm (started at 10mm, felt like too much)
  • Attempted to roll hips forward as much as I could

Results : Rolling my hips forward seemed to help a lot with my lower back pain. It’s still there, but I think that’s a factor of “riding through the pain” for the last 10 days or so.

I have 4 questions:

At the top of my pedal stroke, I feel tightness by my groin/hip. Is there a good stretch or fit change I can do to help alleviate this?

To roll my hips forward I have to sit on the very nose of my specialized power seat. This puts a lot of pressure on the perineum (I believe)…basically a lot of pressure on what feels like soft tissue. I can handle it for an hour on the trainer but can’t imagine this on a 4 hour ride. My saddle is nose-down 3*. Would setting it level help with this? Any other suggestions?

Because I’m sitting on the nose to roll my hips forward, I feel a hair far forward in general. Oddly enough I felt less quad reliant today than i did in fit #2. Should I move my saddle further aft?

Maintaining this hips forward position actually required a lot of concentration, and at the end of my workout I had a tendency to let myself get a little rounded and sloppy. Do I just need to keep practicing this position and eventually will do it instinctually?

Sorry for the question bomb. Happy to be getting somewhere!

So just to be clear about how you should sit on a Power (or any sub-nosed) saddle….you basically want to sit so your “dangly down” parts are…well, you know…dangling down in front of the saddle.

On a traditional saddle, they would be compressed but since a Power saddle is designed to be shorter in the front (hence the reason the nose should be 2-3cm further back than you previous saddle nose), your gentle bits are in front of the saddle nose.

Rotating your hips properly will place more pressure on the perineum than anchoring your sit bones bower….it may take a bit for you to adjust to this and develop some “taint toughness”, but you will adapt.

Your hip rotation does look better in the image above. I’d like to see even more, but you are a tall guy and it is really hard for guys your size to get enough stretch on mass-produced bikes.

7 & 10 mm are big jumps. Really you should be moving 1 variable, 2-3 mm at a time and noting the difference. Start with height. For height changes, consider better or worse ease and smoothness of pedalling. For saddle fore and aft, consider more or less core engagement when balancing with hands off the bar.

After noting the changes from the first movement, try another movement of the same variable, in the same direction, and compare that to the previous one. Has it made things better or worse? Then try it again and compare it to the previous position. If it keeps getting better, chances are the movement is heading the right way, and if worse vice versa. These tests (if starting lower) can go through a range where it gets better, then there’s no difference (your fit window), and then it gets worse. You’re looking to get within the can’t tell the difference range.

From the KOPS and seat tube pictures we seem to have established that you’re further forward. As @mcneese.chad says, either the reduced bar height or saddle movement forward (or both) could have contributed to the increased hand pressure. I’d put the bar height back to the original height (as your shoulders look rounded in the lower position), establish saddle position first, as described above and then try the drop again and see what happens to hand pressure when you remove the spacer again.

Kneeling lunges. Fit changes as described above, shorter cranks. If it wasn’t there before it would probably be the fit changes. Join a yoga class, it’ll be one of the best things you do for life in general as you age.

Sure experiment with the tilt but perhaps your original saddle was a better fit for you?

You’re looking for a nice balance between quads and hams. Going back with the saddle will engage the hams.

Get the fit right and this shouldn’t feel like an effort.

HTH

1 Like

Firstly, thank you for your reply and I am sorry for my late reaction. When I need to write longer text in English, I put it off as it takes me some time to create :slight_smile:

You are right that Look has a modular “matrix” and by rotating (only if that would be so easy, it gets stuck!) it you change your effective crank length. However, they do make two sizes 170-172.5-175 and 165-167.5-170. I have the first one and would have to buy new cranks if wanting to go even shorter. My older bike is even worse because I have a spider power meter that works with Rotor 3d24 cranks that are out of production. It is not impossible, just saying it would be more expensive to try, hence I haven’t done so yet.

I also must explain that when I was changing my position myself previously I ended up in an old-man’s position (too far back, too low saddle and bars too high) and wasn’t comfortable - lower back hurt. My fitter fixed that immediately. Now being slightly more experienced I try both directions “more aero” vs “more comfortable” and more aero wins for me for comfort. I’ll put down my measures later on. Back to your suggestion of staggered stance. I realized that my fitter left my cleat a little more forward on my “shorter” leg as he was trying to fix my pelvis being sideways on the saddle. He explained that my reach was too long (and bars too high) but was surprised that I stayed sideways even after shortening of the reach. He also checked my leg length a couple of times and pelvis symmetry but concluded that the asymmetry was coming from my thoracic spine (left shoulder higher hence better reach and the pelvis was twisted to the right to compensate on the “shorter” side). All this to say that my legs are of equal length. I had that checked also by physiotherapist who didn’t find any problems except perhaps smaller hip internal rotation (and anterior pelvic tilt which is obvious just by looking at me). But anyways, since you mentioned I might try the staggered stance and my fitter was willing to try it (other bike, other shoes) I did move my cleat on my right leg slightly forward (just about 2 mm) right away and tested it for a couple of days. I just couldn’t make it work and my right hip felt crammed (for lack of a better word).

Some parameters. I am 190 cm tall and skinny (62kg). Inner thigh measures at 90.5 cm with saddle being just above 79 cm high. Saddle setback is 7.2 cm (long nose saddle) which seems just right. Anything closer to the bottom bracket and I feel the weight in my shoulders. Slight downwards tilt of 1 degree and my levers are around 8 cm lower than my saddle (72 cm from the nose of the saddle). My bars are also slammed which actually relieves some pressure from my hands (one cm up and I feel my hands too much). If I move my saddle lower I get lower back issues. Saddle higher means the SI joint, hip, outside knee or ball of the foot problems. So right now I’ll keep 1 mm shim under my right leg which gets me a better contact with saddle and removes knee issues. My hip is not sorted still but other than even shorter cranks I am out of ideas.

If you are unstable your adductors will compensate by trying to stabilize your pelvis on the saddle. The groin pain and fatigue could be from this. Do you have hip rock on the bike??

With the pelvis obliquely sitting on the saddle, this isn’t an easy fix. It’s a long term project to regain pelvic symmetry. Through habitual tendencies and routines in our everyday life, it’s possible your body is compensating itself through twisting and the torsion is coming out on the bike. Since your feet are locked in hands on the hoods, pelvis takes the twist manifestation. Start looking into your off the bike.

Glute medius work. Adductor strengthening. Stretching and hip mobility.

Not to be harsh but a 1mm shim is useless imo. Are you dropping your hip still? 1mm is negligible.

Because you are twisted and unable to sit proper on the saddle you will have muscle asymmetry so you will need to strengthen off the bike and one leg at a time.

If you are highly asymmetrical in a symmetrical sport, comfort is hard to come by.

How do I know all this stuff? Lol well I have similar issues. Pelvis is rotated. Right hip forward left back. Let hip drop. I pretty much lost faith in bike fitters around what’s I’m from. I’ve figured out my own stuff with the help of people like Chad and Steve Hogg. Experimenting.

Also it might be worth trying to rotate your saddle nose a smidge towards the hip that is Forward.

No one talks much about proprioception but that could also be influencing your pelvic rotation.

Sounds crazy but next time you are on the bike get warmed up. Practise closing one eye at a time. With one eye converted do you regain some balance or symmetrical feeling? Try it and let me know.

1 Like

I’m traveling soon and renting a KHS Flite 900. Here are the differences to my Tarmac:

From here: Compare: Specialized Tarmac SL7 2021: 58 -VS- KHS Flite 900 2020: L/58 -VS-

Any tips on adjusting my fit measurements from Tarmac, to use them on the KHS?

When I’ve hired a bike other than saddle height and pedals there’s not been much to it. The last time I hired they did ask for measurements for the top of hoods, drop, top tube length etc and probably used different stems (different angles/ length) and different spacer to approximately match that. I’ve never travelled more than a few weeks that would justify being too concerned. Coincidentally my next hire bike will be a Tarmac; how does it ride?

Biggest issue you will need to address is the taller stack on the KHS…depending on how many spacers you have on your Tarmac, it may be challenge or you may just have to slam the stem on the KHS.

Then check and see how long the stem is….your reach is already gonna be 8mm shorter, but if the stem is shorter as well, it will be even worse. Ask them if they have a longer stem they could swap out.

2 Likes

Has anyone had issues with their MCL hurting while riding? could this be foot being set too wide?

I demoed the Tarmac in Santa Cruz. They are a nice ride. Dura ace vs Sram will be your choice (maybe).
Dura ace- 1 lever for front and 1 for rear derailleur - normal left right combo.
SRAM- press both left and right lever at the same time to shift the front derailleur.

1 Like

Cheers. Its UDi2 according to their hire page.

Rent a bike in Calpe? - Bike rental Spain | Vuelta Turistica (vuelta-turistica.com)

1 Like

There could be a few causes of medial pain, things to consider as well as bringing feet inboard:

Ensure foot is in natural position
Use pedals with less float
Support fore-foot varus
Increase arch support

If you suspect it’s width related is that because you’ve just altered it? Maybe get a mate with a laser line to watch the knee tracking.

Knee tracking is huge for sure. Arch support is often overlooked and canting of the foot. If the arch is caving due to lack of support and also pronating it can load the medial knee.

Get assessed for varus
Check your knee tracking
Are you sitting square on the saddle?
Arch support g2620
Wedging

So, I tore a meniscus, among other internal damages in March last year. Havent really been back to full fitnes since due to reoccuring issues, some the same, some different.

already had a bikefit, went back a few months ago and he put my cleats all the way in, so my feet were very wide, as well as another wedge under each forefoot 2x Big in inside, alrdy have SIDAS insoles. Felt alright? didn’t feel like it made anything better or worse, I was just going to get fit checked and to set up my speedplays. they did the fit on a set of wahoo rollers and not the full RETUL so it felt a little half assed.

I’m aware bikefit won’t fix my injuries, just trying to get myself in the best place possible. I have a laser level I can use to check tracking. I think when my feet were wide, the knee was caving in at the bottom of the pedalstroke if anything.

@Sushirockstar FYI

The Tarmac came after my gen1 Domane:

which had a much taller stack than the KHS:

to be honest it took the better part of a year to get comfortable on the more aggressive geometry of the Tarmac.

While traveling I’m just riding for consistency. I’ll just focus on stack and reach to rough in the fit for a couple rides.

By the way

All spacers still on the Tarmac, and I never had a problem with the even taller stack on the Domane!

2 Likes

:rofl: :rofl:

I’m very lucky…almost 57 and I am still damn near slamming my stem (only a 1cm spacer on my TCR).

Figure out how many spacers you have on the Tarmac in MM and then just adjust as necessary for the rental. Sounds like you should be able to replicate your position, jsut with fewer spacers. So if you have 30mm of spacers on the Tarmac, you’ll only need 12mm of spacers on the KHS.

And check the stem length…it will almost certainly be shorter than your Tarmac.

2 Likes

Adding to stem considerations, handlebar reach and even the component group in use (actual grip location on the hood, if different between bikes) can lead to different Functional Reach when all is said & done.

May not matter depending on the time on the bike and goals, but these details get missed on occasion when comparing fits.

2 Likes