Should You Ride Shorter Cranks On Your Bike? | GCN Tech Clinic

Using longer cranks not only closes down the hip angle, it also tightens the knee angle. It has the same effect of reducing saddle height. If you swapped from 170 to 172.5 you would have to drop saddle by 2.5mm to maintain same knee bend. Then at the top of the stroke your knee is coming up an extra 2.5mm thus giving the effect of dropping saddle by 5mm therefore increasing load on knees.

The 105 chainrings are not compatible with the R8000 crankset. I tried this about two weeks ago, and one of the Ultegra arms has a little "swoosh" that makes the 105 chain rings not fit.

I've recently upgraded from 175 to 200 mm cranks on my mountainbike. Should have done this years ago. The amount of torque I can put out now is enormous. I am 2 metres 6, inseam is 104 cm. crancks should be 10% of you length, or 20% of your inseam.

Ollie: Nice job explaining the forces in short-vs-longer cranks and disc braking.

Knee Pain FYI: Shorter cranks (150-165mm) are often used with recumbents due to the rider being very fixed in position (i.e. no shifting/standing) and the not uncommon consequent knee pain that "regular" length cranks cause. For uprights, apart from the usual seat and pedal positioning solutions, this MAY be worth a try.

Get the cassette, if you don’t have it. I put a 32t cassette on my 52/36 chainring and what a difference. 52x25 is no longer cross chained. 😀

For the person who wanted to powder coat, why not investigate whether you could get the chainrings re-anodized.

It’s sad all those nice tools are just decoration

My next bike upgrade....
Dr Squatch soap.

Anodizing is an option for colored chainrings

remember that with shorter cranks you will need to raise your saddle. A smaller crank will describe a smaller circle (pi x d) so your cadence will rise slightly. Wiggins used 170mm on his road bikes and he is over 6'

Shorter cranks don't mean less torque at all. If we rode by just hanging a weight off the pedal then that might be true. But we ride by pushing the pedal with our foot, which is attached to our lower leg, which is attached to our upper leg, which is attached to our torso. It's all a system of levers at different angles, powered by muscles that have to contract, the performance of which is related to how far and fast they have to move, and ultimately limited (in anything other than a sprint) by your aerobic capacity.
Even if you could argue that shorter cranks might have less torque, the counter argument is that you can spin a higher cadence for the same pedal force and pedal speed, meaning power is unaffected.

Interesting how short cranks are now better for hip angle when for decades short people were told they'd get used to the same length someone five foot ten would be comfortable on.

Longer or shorter cranks? Let's look at this like we would decide what size of chainrings to equip. After all, the pedals are going around in circles, correct?

In terms of efficiency, it takes more effort/energy to turn a 53 tooth chainring than a 50 tooth compact chainring. It easier to turn the small ring, thus less energy.

A smaller crank will then be easier to spin around because its radius is shorter and is able to travel faster around its circumference, so you can maintain a high cadence longer.

And Mickie Freiburg used SUPER long crank arms when he became a track cycling world champ, as this suited HIM at that time. We're all a bit weird and different from each other, so if one has the possibility try something new/different - go ahead!

tiagra cranks work just fine, the spacing difference is practically nothing. The same for mixing 5800/5800/9000 and 7000/8000/9100 cranks and FD, a half millimeter difference is nothing. The real question is why bother, 34/36 is only a 5 rpm difference in gearing. The cassette is more of where you should look, 32 or 34 in the back.

For the guy that wanted grommets or plugs for his carbon frame holes he's no longer going to need, try a bit of plumber's putty. You can dye it (within reason), it's waterproof and, if you get sick of it, you can scoop it out with a dental pick and wipe it right off.

Ollie mentions that with different crank lengths, altered torque doesn’t matter much because you can simply change gears. But isn’t it so that with a longer (crank) arm, you generate more torque with the same pedal force? Torque = force x arm. So changing gears is another matter? Of course, this is apart from the whole biomechanical issue, but still.

Super like for the response about front derailleurs.
Really, if you can't set-up a front mech maybe bike mechanic is not the right career.

As a technical, nerdy engineer, I really enjoyed Ollie’s well thought out, detailed explanations on this episode. Thanks Ollie 🙂

Frame grommets: black Sugru, works really really well

Should you ride shorter cranks? No. What you should do is test various crank lenghts. My local shop had a power meter hooked up to a fit bike. I tested 175, 177.5, and 180 length cranks. The test was holding a harder pace for 5 minutes. Then look at what the heart rate was. 177.5s lowered my hearrate (for the same output/time) by 10% over 175s. 180 was only 5% better thann 175. Unfortunately no-one makes 177.5 anymore. So all my bikes have 180 (the next best thing). Oh, my inseam is 38 inches. Get the test done, find out what works best for your leg lenght and spin style. (The best way to cofirm results would be to do the test 3-ish times over a period of several weeks. It's also best to do the test mid season when your legs are in the zone - i.e. not at the end of the season when your legs are toast, not at the beginning of the season when you're legs aren't up to speed yet).

I would like to inquire about something؟!
Firstly. I am a novice in riding this biking rod.
Secondly, I want an inquiry about how to run it for a big time and for a great distance every day I go by 6 kilometers but I can not run it for a large distance because myself short if I want an answer to all this please answer me as soon.

Hell no i like my crank arms

You could powder coat the chain ring but not the teeth?

For that Canyon bike, to cover the hole i use a silicone glue, that will make it a great water resistance

Concerning holes in the frame: What about just putting in a drop of polymer kit?

Sir I want to know how length the longest roadbike crank?

If I’m reducing my crank length from 172.5 to 160 or 165 do I need to change cassette or anything else as Ive heard people saying you should.

I had a cheap so-called mountain bike in the 90s with 28/38/48 chainrings attached to 1-piece 165mm cranks & a 28-14 5-speed cluster. I rarely used the 28t chainring & was tired of running out of gears at the top end. So I swapped the crank out for a 115mm & trained myself to pedal at about 140rpm to maintain linear speed of the pedals. It took a few weeks to get used to it but it was great being able to go faster than 50 km/hr without spinning out.

You are NOT going to be able to recruit your muscles in a greater range of motion on a shorter cranks - quite the opposite, they are going to be recruited in a smaller range of motion. However, you ARE going to be able to recruit your muscles in a more efficient range of motion.🤓

My serious triathlete friends, even tall ones, are using 165 mm cranks

172.5mm to 160mm cranks here and the difference is amazing. I can get more aero, stay aero longer and have more power in an aero position thanks to the shorter cranks opening up my hip angle a few degrees.

I have 170 crank and Im very happy with! Im 5.7' The problem was the Saddle's spend close to $ 400 in 3 different brands expecting to fine the right one but didn't work till last week order one from a popular website which finally was what have been looking for. The new Saddle solve severa critical l issue's.Anyway for a while fallow industries Websites BS promotions stuff etc... its up to individuals needs & understandings !!!