As linked earlier, Bike Fit Advisor on YT has some great content. I have watched many of his videos and they offer a good range of comments on the ‘how and why’ in the ones I’ve seen. He pretty much lives the bike fit world and is the one I start with when I am looking for new and different points of view.
Custom Bike Fit seems to have a good library, but I admit to not watching many of his vids previously. So I can’t speak to the quality or depth.
Let me know if those don’t get to your needs, and I will see if I can help further.
Thanks @mcneese.chad I will check those out. The engineer in me is curious about a couple of degrees of flexion or agonizing over 2.5mm of crank length. Some of these factors seem so small in relation to the range and variability of the human body.
Oh yeah, as a mechanical designer first, that fell into bike fitting via shared interest and the parallels of interesting in angles and alignment, I can totally sympathize.
There are real impacts that can be made via fitting. But I recognize and share with all my customers, that “close counts” in most cases.
I agree that there can be overemphasis on minute details and changes that make little difference. Saddle height for one, is a setting that has a workable range of at least 5mm that most people would likely never notice. Difference in socks, bibs & chamois, and others can easily alter “the perfect” fit.
Any fit I do is considered to be in what I call a “workable range”. That means I tell the customer they are free to experiment or adjust their setup within some range (varies with each particular adjustment, but 3-5mm plus or minus is typical for my recommendation). This is largely because of the static nature of bike fitting on the trainer, and the inevitable differences when we finally get on the road with the new setup. It also relates to the need for some riders to adapt to the changes (sometimes quite dramatic) that may show other issues not present in the short time of the fitting process.
There are hairs that people split with setup or component choices that are best left to the professionals. The majority of us will never know or benefit from that level of scrutiny and review.
That said, most of my customers come to me with discomfort or injuries as a result of improper fitting, incorrect bike size, or unnoticed issues. My proudest moments in fitting come from hearing a customer after a fit that say something like “I can ride so much longer, further, faster (or other improvements) after the fit” and they are so happy with that improvement.
My primary goal in all fits is to make the rider happy and comfortable on the bike. The other performance and fit needs are in there, but I want people to be able to enjoy the bike exactly as they hope to do.
There’s a psychological element as well - sometimes the mechanically-unsignificant change will have a great mental impact. I fitted ski boots for a while - I could expand on some of these “mechanically-unsignificant changes” we sometimes used…
I get the “placebo effect” can be quite powerful and since I am more engineer mechanical than bio mechanical I have a challenge getting my head around the minute changes to a machine with large tolerances. Big changes I totally see, but mm is harder. I also shake my head at the inverse placebo effect where people stick to things dogmatically - those 2mm of Q-factor will ruin my knees etc.
BTW - do you ever get out to the iVelo Crit events? Going to try and get that way this summer for some of the fixed-gear nights
I moved it forward 10mm and did an outdoor and trainer ride. Def feels better on my hamstrings! Here’s the link to a video. I do think I may be rocking more now though.
Do you normally pedal so toe-down? It looks to me like you are reaching a little at the point where you have most leg extension, meaning your saddle might be a little on the high side. If true, this could be contributing to your rocking. Or if you have always pedalled with your toes down, it might be a complete red herring.
I agree, the final ankle movement and toe point looks like a “hitch”. These can happen as a way for your body to allow the stroke to work, even f the saddle is too high.
I’d drop the saddle 5mm and retry, watching leg angle and ankle movement for changes.
Thanks for taking the time to look at this guys (@DuncanM23).
I jumped on to get this one after my run this morning. Had to do it 2 times cause the first one I was so focused on my ankle movement I felt like I was influencing it too much. This one is more natural. Only change was the 5mm drop.
Looking at it again and knowing I’m just about maxed out on my saddle forward position I’m wondering if I actually need a smaller frame. And maybe shorter cranks? I’m in 172.5mm cranks right now.
Neither of these are in the cards financially right now, but it might be good to know over the next few years.
That position looks improved to me - do you think you are rocking less?
I agree with Chad - I don’t think you need a new frame. The saddle position looks OK, and if you want just a little more forwards, you can always go with an inline seatpost. The reach looks sensible, and there’s room to go lower at the front (if you wanted to) with a change of stem. Both those options are much cheaper than changing the frame. Edit - I’m not saying you should make those changes, just that they are available to you.
As for the cranks, I don’t think there’s much in it (I ride 175 on the MTB, 172.5 on the road, and 165 on the fixed, mainly by happenstance, and the differences in position mean I don’t notice the crank length), and if your budget is restricted I wouldn’t spend it on crank length.
Great comments, and I totally agree on the cranks. There is a lot of emphasis on them and little to gain (or lose), IMHO. You look more settled and I would focus on nailing the training as the bike looks pretty solid.
I’ve been using the bike for fast app and it can take some of those measurements from the videos and pictures. It just gives the generic “normal ranges” and I’ve always been inside that but it’s still not near what a good eye of a fitter would be.
Can you explain how one might go about rolling the hips back to engage the sit bones better? I’ve suffered with a lot of numbness because of too much weight on the perineum I think. I assumed it would be related to excessive handlebar reach, however I have the same problem on both my road and cx bikes and the reach differs by roughly 7cm!
Reach is one option. Also look at saddle to bar drop. Lower bars can lead to more hip rotation.
You might start by taking photos on bikes in your natural position. Make sure to implement the same one you use that leads to the issue. So, hoods (with or without major elbow bend), drops, etc and mimic the full position.
Then identify the flat part of your hips below your spine and eyeball that angle.
Its entirely possible that you need that forward lean. If so, you may want to look at different saddles. But that is a consideration after looking at the hip tilt and possible reasons for it.
Your flexibility (or lack of it) can also be important to consider.
My saddle to bar drop on my cx bike is very little, despite being 6"3. Again, this is different (the drop to the bars is less) than my road bike which presents the same issues. I am comfortable in my arms (elbows bent and shoulders relaxed) and can pass the balance test (used for saddle for/aft) fairly comfortably when working at tempo intensity.
I took some video the other day which I’ll share with you as soon as I can get it uploaded.
I do suspect my saddle to be a bit too narrow (new one on the way) but im worried that, if my issue is pelvis tilt, then saddle width wont solve it since I won’t be sat on my sit bones.
Flexibility, I can’t touch my toes so theres definitely room for improvement there which I’m working on
