I have changed my cranks from 170 to 160mm just before Christmas and raised my saddle by 10mm. I do not have any pain problems, I received a bonus from work and decided to splash out. I am 5' 9" 1.75m tall and 57 years old pushing a good 40 pounds (18.18 kilos) overweight. I am astounded by how much difference the shorter cranks have made. I am able to spin up so much more easily and faster than before. I am also able to maintain a more consistent speed and use the big ring when in the past I would have to drop down to the smaller one. I don't have a power meter so cannot say if I am producing more power but my average speed has gone up between 1-1.5mph (1.6-2.41kph). I will never go back to longer cranks again. My bike is an aluminium gravel frame with a carbon fork built from parts taken from my last bike and changed where necessary, eg 12mm through axles from QR. Just had a saddle fit and got footboards today as well so looking forward to seeing any further improvements with being more comfortable. Getting very close to an average of 15mph 24kph on my 15.5 mile 25km commute to work and back, total 31 miles 50 km. Not done that for over 20 years.
Going for shorter cranks seems to hav gotten common for mountain bikers. I also went shorter, I went from 175mm to 165mm, I did not notice any negative effects. I got the cranks offered for a good price so grabbed it. I'm glad I tried it. It also means better crank clearnace.
@@brunoj6146 No, I've changed nothing else on the bike, and based on what I've seen/ felt so far, I dont think I will. It is just more efficient and a stronger pedal stroke. My next video will be about power output comparisons. Keep a look out for this in the next few days...
If you raise your seat 15mm, you also have to put your forward for 5mm (1/3rd) and your handlebar should be 15mm higher so you keep your postion the same. right now shorter cranks open up the hip. But as you raise the seat, your hips closes a bit as the height diffrence between sadle and handlebar is bigger. So the changes you see right now are not as good as they should be. But otherwise great video, Im also thinking to go shorter.
I agree. However my Specialized Tarmac has a proprietary stem, so I would have to get a new stem at a different angle, or possibly even one that I could flip upside down (this one wont). Also in this video I tried to keep things as simple as possible by "only" manipulating one variable which was saddle height.
I was going to write something very similar. I went from 172.5 to 165 and 160 on my road and gravel bikes respectively. It is a smaller jump than stated in the video but it has saved my lower back, knees and hips (arthritis in this old Canadian). The saddle needed to move horizontally and vertically, and the bars vertically to keep everything else the same. Great video!
@@TheNovaNorm Thanks! Yes as a bike fitter I know that one small change starts a butterfly effect which can end up altering the space/ time continuum...
I guess it's not for everyone. I tried shorting my cranks from 172.5 to 160mm. It gave me numb hands and a stiff neck since the handlebar is slammed and integrated.
I don't believe it's really about going "shorter". I think we are just finding the right sizing for us, or niggles/age and not just riding what is industry standard provides. Adaptation phase can be up to a month or two. Give it time and plenty of rides. I'm still in that phase going from 170mm to 160mm. But still, so far so good. Hip and knee niggles have gone bye, bye and I feel way more symmetrical and more power on the bike. Experiment with the setback as well. I pulled my saddle aft about 8mm after installing the 160mm cranks and it felt even better!! I also pulled the cleats as far back as they would go on my size 46 Bont Vapor S and that felt AGAIN better with EVEN MORE power. Don't be scared to play around with it. Mark before you move in case it doesn't work out. Good luck.
Cheers. Yes I think we are beholden to industry norms. I'll likely make a few further adjustments to both of my bikes to tweak the fit. Thanks for your input!
@@podiumphysio657 I also forgot to mention. I narrowed my stance by 4mm on both sides with the reduction of the cranks. I was riding Shimano +4mm pedals and went down to the standard 52mm Shimano pedals. I had both pair on hand and have been experimenting extensively with this. So far so good.
Thank you for your interesting videos. I was victim of a hit and run accident 2 years ago and had extensive surgery on my left knee joint. Since then I have been looking for ways to decrease the discomfort that starts after 50 Km on a ride and thought that may be a shorter crank could help. Looking forward to your next videos and analysis.
Yes you would definitely expect shorter cranks to reduce the knee angle range of motion as well as for the hip. You might also want to look at other "knee unloading strategies". I've seen examples of extreme cases where people have used different cleat positioning on L versus R shoes, and even different length cranks L side versus R side.
3:41 Please correct me if I'm wrong, but this shouldn't have changed. The reason it's different is that you did not compensate for the saddle height increase with the change in saddle offset and the seat tube is angled
Hey Stan. I agree. Hence the shoulder shrug! I dont know if this is an artefact of the bike fitting app I use, or a subconscious change in posture... I frequently find in my bike fitting work that I'm planning a very simple and obvious mechanical adjustment to the bike, which should have a very predictable outcome, then I make the adjustment and get a completely unplanned result, sometimes even the opposite of what I was expecting. This is one reason for my increasing number of grey hairs...
I also have a tarmac sl7 with slammed integrated handlebar. Since I installed 160mm crank it made my bike felt so low and stretched. I get stiffed neck and hand numb.
If you raised your handlebars at the same time as moving to shorter cranks then this is understandable. Unfortunately, as any bike fitter will tell you, having an integrated front end is wonderful if your bike fit is perfect, but terrible if you want to make changes. This is one reason why I have resisted using integrated bars and stems on my bikes.
I think you have raise the saddle height too high and if you raise the saddle, you need to move it like about 5mm forward to maintain the hip to BB distance else you will be seated too far back with the 15mm increase in saddle height.
@@podiumphysio657 Your seat post is sloped back. 15mm is too much if you did not move the saddle forward. If you were to raise and not move it forward, it is too high. Normally every 5mm differential of the crank length is 3mm in saddle height not 5mm. Think triangles not in just a straight line. You distance from the BB is your reference not the entire length from saddle to pedal axle.
@@lordalfa600 Ok. At some point soon I'll rework the set up on both bikes using my Bike Fit Video analysis so that both are optimised for body angles, balance, comfort and performance feel. I'm sure that a few tweaks will help for both bikes. This is actually the first time I've examined my own bike fit for many years.
Everyone's going shorter! And yes I've recycled the thumbnail just with different text. Hopefully people will realise that it is a different video from the first.
you can also try moving the seat forward to open the hip angle. I think the UCI rule is the front of the saddle should be at least 5cm back from the vertical drawn through the bottom bracket spindle.This can give an effective seat post angle of 75 or 76 degrees depending on leg length, which can be better than the standard 73 degrees if you are a long legged person
@@user-sc4sp6tb2j i think the old rule of thumb that the knee should be over the pedal spindle is a myth, but would be interested to hear the physio opinion. You hear people say the same thing about lifting weight in a squat, but when you look at what good lifters actually do their knees are often a long way in front. My experience is that seat height is what makes a real difference to knees
I am moving to 145 mm cranks. Took me five years to realise that I, 1.6 metres tall, am stupid to be riding 170mm cranks. Climbing was never easy but I persevered. But if I am not using the same handlebars, frame size, even wheels (650b over 700c) as the taller people around me, why should cranks be the same? Costs me a bomb but I am going custom.
Hmmm. I've never seen cranks that short, certainly not from the larger manufacturers, so custom built might be necessary. I've been using mine for a month now and I think they are brilliant!
Would've been better to see the side by side comparison with the same bike. Anyhow, I think you can do better by turning your seatpost 180 degree forward and moving your saddle higher. If it's not possible, buy a zero offset seatpost.
Yes would dearly have liked to do the comparison on the same bike, but I really didnt want to go pulling the cranks out repeatedly, given that I'm planning to do several further comparisons. Maybe I should just by another Tarmac for that purpose!
@@podiumphysio657 Understood ... I thought you filmed a video before changing your crank. That's ok. Give the seatpost change a try when you have time. It will open your hip angle even more, but you might have to get a longer Stem if your handle bar is too close to your body.
@@musclelessfitness2045 Yes interesting idea. I've been to bike fitting conferences where they talk a lot about balance and control over the bike, such as the "Steve Hogg" test of taking your hands off the bars to see if you can hold the position without support. The further forward your saddle and hips go, the less likely that will be possible. It will also place more weight on your hands. It is a typical bike fit scenario where there is no "right answer" it more depends on the priorities of the rider
This is great… i have issues with hips. Arthritis on the inside of the joints. Have you tried wider Q factor also? I found it made a big difference on my mountain bike.
@@podiumphysio657 Yeah, all my hip pain went away on the MTB because with a wider qfactor you're moving the hips further apart and away from impingement.
Q-factor tends to be around 150mm for a road bike and 170mm for a MTB... Not to sure what mine is exactly but definitely made a difference to my hip impingements.
1:34 looks quite uncomfortable. Bent back, the neck, and load on the hands. But road bikes are cramped too. It never looked right to me from a comfort standpoint, but a road bike is made for speed not comfort. I'm curious if or when your wrists hurt, or get armpump. 🤔 I have loose wrists so use wrsit braces. But I bet it would be horrible without on a road bike, but never tried one. Also sitting so far back, in relation to the bottom bracket. Horrible. Very different to a modern enduro bike. Saddle tip is about above bb. I also us emid foot position with Catalyst pedals.
Interesting. As I said in the vid my hips are arthritic so I'm going to look awkward no matter what! But no I dont have any wrist problems. In a past life I was a national level pole vaulter so my grip strength and stability is way above the norm.
Just train your wrist. I have small wrist that get injured often. After training it with high rep exercises every morning it get better, tendon get stronger and I never have wrist pain again when riding or lifting something heavy.
I’m also trialling the move from 170 to 160mm cranks. I’m height challenged at 167.5cm and I wanted to see if shorter cranks work better. I’ve been having hip pain for some time, in particular pain in the glute medius. Just out of curiosity, what does your hip pain feel like?
That could be a very long answer... I have pain coming from the hip joint which I normally feel in the front of the hip, down the thigh and I think also refers into my knee area. After rides it can be a big problem but at other times it is more manageable. I also get lateral hip pain which is coming from my trochanteric bursa and Gluteus Medius tendon. If my cycling volume or intensity goes up too much, this area can play up. If you have lateral hip pain it is worth getting assessed for trochanteric bursitis, because there are good treatments for it and good rehabilitative exercises for it as well
@@podiumphysio657 Thank you. Sounds awful : ( I have lots of issues that sound a little like yours. I've had an MRI done, but it didn't reveal much. Back to strength training and core exercises!
@@schadenfreude1057 Bursitis at the hip is easy to define with a clinical assessment. Usually: - weak hip abductors - poor control with single leg squat exercises - acutely tender over the tendon insertion/ bursa area A physio should be able to work this out for you. Sometimes a clinical assessment will be more useful than a MRI
The shorter cranks feel good to me. It is easier for me to get over the top of the pedal stroke and it feels like I'm more in the "sweet spot". I've done 3 or 4 outdoor rides with them so far and I will admit that it feels different, but certainly not worse. I think generally across a variety of situations (steady group riding, end of ride sprint, uphill sprint) it feels comfortable and more efficient.
