Knee Extension & Saddle Height | Rules, Nuances, and the Ankle's Role 

Neat graphic tool. Yes, the ankle is important and is often forgotten. For what it's worth, I have found that as one raises the seat, a rider (like myself) will often unconsciously raise one's heel height. And conversely as one lowers the seat, a rider seems to automatically lower the heel to be almost be parallel to the ground. As I approach 66 years old, I find that if my seat is too high, my lower back will bother me during the ride or later in the evening. And also recently, the back of my knee may bark at me. If my seat is too low, my back may be fine, but the front of my knees may bother me when I get off the bike, particularly when going up or down stairs. Sometimes I often quick check my seat height my sitting on the saddle and putting my heels on the pedals and spin backwards to see if my pelvis is rocking from side to side. If it is, I need to lower the seat if I want to avoid back pain. I also have to adjust my seat by a few millimeters up or down according to the season and how much clothes I may be wearing. For example, two or three pairs of tights versus only a single pair of riding shorts with a thin chamois. I will also mark the differing seasonal seat heights with a marker if the post is silver, or I may even use a hack saw if the post is black, just enough to break through the black coating so that I can see a seat height mark. The one thing that is tougher is if I buy a seat that is softer than my last one. Accounting for how much I might sink into the seat while riding is a bit tougher to estimate and its influence on the correct height.----My back will complain with only being off by a few millimeters too high. So I find I am using that as a sign that my seat needs to go down, if I set it too high in an effort to accommodate a softer seat. And then one has the fore and aft position and the seat tilt. --- Don't get me started. I sometimes wish there was a computerized seat post with a computerized seat bolting system that would automatically put you into the right position and right height after riding only just a few miles.---Getting the right seat height and position for me is the number one thing that discourages me from buying a new bike. Just the thought of trying to figure all this out again leaves me exhausted before I even look at a new bike. On my old bikes...I have it pretty much all figured out.....I think....until I get even older I guess.

This is a really great video brother I just went through a $300 fit and I'm struggling with the fitter to justify my desire to be close to a 150 degree angle. I'm at a 146 now. The fitters deal with the general public so their tendency is to recreationally fit and weekend warrior people but as a rider it's important to stay inline with what I'm doing. They're not terribly invested beyond the money for the fit and this is a great reminder.

Verrrrry informative video. Plenty of food for thought. You've made a really great job of this. Thank you for sharing your knowledge. There are so many videos out there, but I honestly think I've landed on the right spot. I'm 64, and I've already learned a lot. Greetings from France. (I've already commented another one of your videos. Great work and research).

Thank you so much for the great contents that you share here on RU-vid :) It helps us cyclists and bikers to understand what’s happening with the body relative to the fitment of the bike.

Great video, thank you so much for sharing that link. It's great

Your insight about knee and ankle interplay was amazing. Thank you for this.

great video. much apreciation for bike fit app developer also

Nice job. A complex topic made more understandable.

Watched all your videos. Injured an ankle several years ago. Very experienced rider 60y/o. Inspired by your videos I chipped away mm by mm on fit. Different bike, 40 years later copied old fit. Not good. Summary as lifelong heel driver raised saddle from baseline, moved saddle back with setback post. Obsessed over tilt and bar position. Lucked out with saddle found as a pig on a poke! Results! Pain free. Riding fixed track bike on road faster than geared 10 years ago. No pain! Who would have expected this!

Great video absent of superfluous information.

Great great video...brilliant gonna check my set up...love the free software..

Where can I give a double thumbs up? Brilliant

Dialing in seat height and fore-aft position for that Goldilocks spot is like trying to solve a Rubiks cube. After months of adjustments and testing I finally got my saddle right on my XC Mtn bike. The bike shop setup a "loose" ballpark fit which was fine for shorter rides, but for long climbs and longer distances, this was not good enough. I used to multiple methods to get there.. the 109% to get in the ballpark on height and then moving the saddle forward to get the knee closer to the end of the of the crank arm. And then there is saddle tilt which is different for every make. starting at 0 degrees and micro adjusting, for me the nose down. Having an expert getting there would have been much easier and even ensure cleats and shoes are properly setup. having found success with the Mtn bike, I thought these methods would work also for the road bike. I can't say that the fit crosses over all that well, as the saddle seems a bit low, especially noticeable on climbing. My point being that knee angle seems especially important for road fits and every bike has its own fit. But I have also learned that the saddle shape is important with relation to where saddle height and bar height fall. This channel has really helped me learn more about bike fits. Thanks for all the tips and great content here!

Hello there! You're channel is incredibly insightful and I use it pretty much as my guide book whenever I have an issue. I'm currently cycling from China back to the UK and recently changed my saddle fore/aft by about 5mm. Moving the saddle forward. This has given me alot more comfort in both shoulders and saddle comfort however it seems to have caused some heel drop that has caused discomfort. Is there anyway I can do the non static bike check video without using a trainer? I'm currently on the road and dont have access to a trainer. I'm assuming doing the video with the chain off would have a different affect on pedal style? Any help would be greatly appreciated, keep doing what you doing and I dream of coming to you one day with all of your tech and you showing me just how far from perfect my cycling position is! hahaha

A+ on your logo. Brilliant.

This is such a great chanel, very very interesting and well put together. Definitely give the software a try. Thank you very much for your time and effort on these videos. Cheers Mike.

Excellent video.

great job mate!!

great content, will try it out soon.

Just stumbled across this channel and really enjoying it. I thought it was really interesting how much the tensioner was moving in the opening bike shot. Indicates variable pedal power or inconsistent movement?

Very informative!!

Thanks for the tool. amazing

Mind blown! I love your content. I wish you were in L.A! Do you recommend any fitters in Los Angeles?

I'm to receive a new saddle today, it will be cool to try this software when sitting it up.

I'm 49 and I've always had my saddle quite high and after getting back into cycling I did a 60 mile sportive the other day and had pain in back of knee and calfs, I lowered my saddle by 5mm and also brought it forward 5mm, felt ok but then I found this app and it told me to bring my saddle down a further 24mm, so I did and also moved it back 5mm again, Feels alot more natural now. Just need to go for a decent ride to try it. Started off with a 150 degree knee angle and 35 degree ankle at bottom of stroke, now its 143 degree knee and 23 degree ankle. Alot more comfortable.

The ankle angle will change with pedaling load, and fatigue. At the end of a long ride could be completely different than what is measured on a trainer after a few minutes warm up, especially if it's a lot of toe-down.

Thanks for sharing this, can't wait to try it out.

Comes across as an excellent tool, thanks for sharing! What method are you using to get the bike in the video properly set up, without perspective/parallax?

As much sense as you make and how logical it sounds all your data can be completely skewed by misplaced lines that you snap from joint to joint (which you did with x-ray vision I guess? because I didn't see you palpate to find the actual joint?) Not saying that they are, I would have no way to know by looking at a video though it's not hard to conceive that a 5 degree error compounded by 3 could easily be made without accurate reference points. Very interesting nonetheless and will make me reconsider my own set-up! Thanks

Thanks awesome tool!

Thanks!, good vid.

COOL IDEA!

One great enhancement to the tool would be an undo/redo feature. It's a fabulous tool

And what is the optimal angle range for the foot? Good video as always, keep it up!.

I love this video and I took a photo of myself. Made the calculation using the app and I found these as the result : my knee angle from full extension is 31.2 degrees. My foot angle from horizontal is 35.1 degrees. Is that good?

I would think that my ankle wouldn't bare the flex when on the maximum of the power I could ad to the pedal. Therefore my question would be that would the measurement be more accurate or more useful when it's been taken during the FTP measurement, so that the flex of my ankle and my knee would be comfortable during close to high stress situations. These forces would probably change the angles on both the knee and the ankle, maybe it's even more useful to check the angles during full power sprints.

Obs fit should be a fcpx plug-in or other (nle) video software plug in. it would require a lot of different knee and shoe wraps that look like those markers on crash test dummy’s. Then you could run a program to spit out angles with no manual inputs by having a marker placed. Get a cgi guy and a coder in a room and it would probably happen quick. You could then increase your sample rate and record riders going through different modes of riding and get a real amazing amount of data without having a pro level budget. The Everyman could buy the spandex markers for $30 and then do it at home. If software was under 150 for the setup I bet the kind of guys who have trainers in the house would buy it. You could also make it a portal for bike fitters to work to help more riders remotely on video calls. Just throwing a thought out there. If you: Automate it and build a community, you change cycling.

Best video so far, keep it up

I've noticed how new pair of bib shorts change the knee angle, fresh new padding is thicker then old used one and sometimes it demands millimeters adjustment to the saddle height

11:20 I find the opposite, for aging knees more extension (less angle) helps as the up stroke doesn't put as much pressure on the knees , ie more optimal leverage. With higher seat post then it puts more body lean, so bars have to come up too.

Great! Finally a good free software! For those who dont have a trainer, does it work to pedal backwards?

That OBS tool looks cool. But there should be some kind of calibration object of known length and angles afixable in plane to the frame to deal with any off-square camera angle as well as auto adjust numerical measurements taken.

What about the top of stroke angle? Do you have a suggested range? Also, if one drops the ankle and just maintains knee extension angle at bottom stroke by lifting the seat, that will open up the top of stroke angle, correct? Some commentary on top of stroke would be greatly appreciated.

In short, this video shows that when you support your foot on the pedal and raise you ankle they knee bends. When you lower your ankle (or heel) your Knee is more straighten. Magic, magic.

Interesting 🙂👍🏻

The question remains what angles of knee & ankle would you consider optimized for let’s say race and touring positions.

Could a higher patella in one of the knees be affecting extension, when everything else on the bike is balanced?

Thx

that rear derailleur wiggle is funny

I would like to ask if for the Two Examples on the video were to adjust the fore & aft of the saddle and tilting the handlebar as the saddle moves, would these also help with the Ankle and Leg Extension? Curious but I know a small increment will reflect on possibly the bike’s handling or the comfort, angle of the foot relative to the ankle, leg extensions etc.

small feet vs large feet has a huge effect on knee flexion as well

I own multiple bikes. My problem is the transition between the two. One bike causes less pain than the other. I made the mistake of removing old cleats without marking them. Now I just can't seem to find a happy medium between the two. I had considered getting a separate pair of shoes just for my B bike. I tried setting up both bikes the same. But unfortunately for my knees, they just don't like my B bike position. I've tried different adjustments one at a time to try and find a sweet spot to no avail. I am a bike mechanic. But setting up my own bike is one of the hardest jobs I've encountered. I almost positive my issues are from the cleat position. But I'm still at a loss to find a position that works for both bikes.

Fantastic tool. Love from Bangladesh.

I dont get it. What's the point and importance of knee flexion angle? And what is the ideal range?

John, if my bike causes no pain anywhere even on quite long rides, and I can sustain a reasonable power output, and seem to be improving (even though I'm well into middle age), is it safe to assume the fit is good? When I see my own shadow it looks reasonable enough. But I watch a lot of your videos and they are having the odd effect of making me paranoid. What if my fit is wrong? Easy solution is to go get a bike fit. But then if nothing SEEMS to be problematic, why? Duo you have any thoughts on this?

Hello, I had a knee replacement surgery and I cannot bend one knee enough to put the from part of the foot on the pedal, I have to use the heel. I thought getting a tall bike and lifting the seat will help but I still cannot. Now I'm thinking on moving the seat as far back as possible the height of the bike might not matter as much as that. What would you recommend?

Good vid, going to have to video myself on the turbo and have a play with this software. Do you have any videos on toe in/toe out? I seem to be most comfortable with my toes out to the limit of adjustment on my spd-sl pedals (I'm very close to rubbing my ankles on the cranks). Is this just an individual thing or a sign that I might need to change something about my setup?

But why does knee bend angle matter? Is there some advantage to minimizing it?

Can't a standing hip hinge movement with forward reaching arms determine the angles naturally?

I have a quick question as far my seat I think I pretty much mastered it my hight is 5 9" tall 32 length.Now relax position and agressive position is fine.when I'm at really low aggressive positions that's when I get neck pain I do have Degenerative neck issues I'm really flexibility guy my legs because I do martial arts . I had to take the spacers out spacers out because relax position bothered my neck.it was tilted to much upright. Even though I have neck issues is there ways I can get comfortable in aero position with out bothering my neck .my stem legnth is 110.

I notice I toe down on my left but my right foot is level. I can only assume my left side/leg is not as loose as my right. No limp in my walk. I am just gonna go with it and enjoy the ride....

is there a way to download this software sir? ☺

is this tool still available? I can't seem to find it

What are you thoughts around a quite extreme heal up / toe down style throughout the whole pedal stroke (assuming a comfortable knee flexion angle)? Would you try to correct it or be satisfied it is part of their natural style?

Awesome tool, just had a play with video of other half, trying to get her set, she pedals with heel up/toe down a bit. What's an excessive (or normal) range for ankle flexion?

Does anyone have something new to say about this theme?

Hi there, App doesn't seem to work with my laptop?

Has this website gone offline?

can you leave the link again, previous for the app, does not work

I guess that site no longer exists?

I love this but is it not the case that at the bottom of the stroke our ankles can make up for what we want to do with our knee angles. However at the top of the stroke (where we can hurt our hips and knees) there is little to nothing we can do to make up for a saddle that is too low... I have to have a saddle height that it far too high to enjoy riding on the flat (but great when climbing), just so that my legs arent coming up too high at the top, as that gives me terrible back pain after 2 hours

The link doesn't work (anymore).

so what do you do if you raise someones seat and they just go more toe down instead of extending the knee? I have about a 136 on a road bike under load. I have to raise my saddle from about 31 inches to 32.5 and a half before the knee starts increasing angle, i just end up more toe down (I have a size 15 shoe which allows this long range). I'm 6 feet tall and by doing the level in the crotch test my inseam is ~34.5 inches. moving the cleat doesn't seem to change this in any meaningful way. I do notice that my heel comes up under heavy loads, decreasing my knee angle

Link not available

website doesn't work anymore

Hi, tried following the link, and looking for the app in Google's app store, but wound up with dead ends, the web page loaded for me, bt only appears as a static picture...any advice? Maybe it's me?

Oval Chainring?

you need a higher shutter speed on your cam ;)

How about spinning pedals in reverse? I mean, in order to transfer power? There was one such a device on the market (can be simply integrated instead of standard BB)... I think it's worth to consider, since very different grups of muscles are working - perhaps more efficient?

Moral of the story: do soft tissue work, and strength training, and sleep well, and eat well, and drink lots of water, and go to the chiropractor and..., etc., etc., etc.

1:47 I don't know why every bike fit video I've seen does this: it shows angles > 90° (both of 'em!) and yet claims those angles are 25 - 35°. The latter range is obtained by the projection of the vertical line and taking the angle between that and the other line. Check out 2:47; it is 152.1°! At least this is correct.

Check out Adam Hansen's foot angle at 17:32 of the video. Quite a large angle at the 6 o'clock position of his right foot. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-zuR1XPA6pw0.html

NONE of this meauring makes any difference UNLESS the rider is measured on watts/kilo output. One can see a wide range of variance amoungst pro riders. They have had extensive evaluation of how many watts/kilo they put out over a pre-detemined distance. It's ALL about V02max and Watts/Kilo. Look at the "bizzare" saddle height Chris Froome maintains. That has been evaluated so many times by his team with regards to watts/kilo. And many riders, ride with toe down or flat or?. All this measuring is just that. For the average person, comfort and perceived output is the best indicator of EXACT proper position-for THAT RIDER. All this stuff is silly.

This is all impractical nonsense for people who wish to use a bicycle not for climbing mountains, not for racing, not for sport but for transportation in a city or town. In most American cities or towns, the automobile is king and on a bicycle one assumes great risk competing with drivers. If such risk is acceptable to you, then you would want a bicycle that is comfortable and as safe as possible. I would choose the sort of bike ridden in Amsterdam, Holland, where it is the common choice for city dwellers. It gives the rider an upright posture, rather than the unendurable forward lean with upper body weight on one's handlebars. Bicycles are no longer made in the USA, and they are ridiculously expensive. They are sold in boutiques, not in bicycle stores or online, where they cannot be examined before purchase. In a bicycle boutique, be prepared for prices above $450 with few accessories. A helmet in such a fancy store is $100., for a plastic and foam chapeau. The USA is now a crazy place to live!

Theoretical bs. Just rely on what you feel!