Hello Hello welcome to today's video, it's another episode of BiteFit Tuesdays and today we are covering Cranklength. What's the right crank length for you? you would the smallest length. What length frame do you write? 170s, 165 and 168. I like a 165. I know because it was tiny. This is basically one of my questions the other way when they come in here. So the crank is the arm, the pedal attached to, the feet attached to, and now it's to a central spindle for the bottom bracket, which is an interesting name, it's not the bottom, the bike and it's not a bracket either, but nonetheless. Crank made, they range from 165 millimeters in two and a half to five millimeter increments all the way up to 175. The most commonly found sizes on bicycles, 165, 170, 172 and a half and 175 in those exact increments. Outside of the arms of the major manufacturers there are smaller and larger sizes. I've been selling and using this crank length as small as 155 millimeters, particularly for small riders, and equally, I mean Shimano makes a lot of noise during crank up all the way up to 180 millimeters. When I bought my first proper road bike it came with 172.5. That's the most common size. Is that right for most people? My findings suggest otherwise, yes, no. If you consider the 172 and a half millimeter crank comes on, basically, most 52 to 46 centimeters of bike. So the kind of the average size of bikes, my best selling crank length by a very, very long way is 170, which doesn't sound like a lot, two and a half millimeter, a two and a half millimeter reduction, doesn't sound like a lot, but when you think about the the biomechanics of it, like your your federal head and side your ace attack, it means your hips, socket, two and a half millimeters of internal rotation, actually, it's quite a lot. And we found that two and a half millimeter reduction in crank length can yield performance improvements. So my instinctive response would be that 170 might be better, but I think this is the case with quite a lot of things in sight when, you know, things like handlebar width of one, everyone runs 42, that actually 40 is our best selling. But that's for another time and another story entirely. I think there's quite a lot of talk about in the media and both on line about reducing the crank length or talking to generally, to war, the generally of the idea or the opinion that short for us better. And generally my finding is that it's not always a 50 to 70's song, I'd say short to tends to be better, but it depends on the function of the riding wall and anything else. A more functional rider tend to be less influenced by crank length because they have function wall allowing to close their hips down better. So what are the problems associated with riding a crank length that's too long? It's quite a lot actually. I mean, so if you've got an individual with some sort of hip impingement, excessive crank length can go as far as causing a ride to list quite heavily to one side. So if you've got a rider who is impinged in one hip, for example, as they come through the top of the stroke, their inability to raise the knee through the top of the stroke essentially sends them off to one side because one way of opening the hip off, opening the hip up, sorry, would be to sit off to one side as a means of opening it up. Now that's a tendency, in fact, almost always cause a saddle problem. So I actually had a lady in here recently who has a severely impinged hip and she's kind of an average height but she has extremely limited mobility in this hip and it was resulting in her listing to one side and she's running 170's I think. We went down to a 155mm crank which has meant that she is now able to sit squarely on the saddle. Now it's seated to relatively short crank but to be honest with you in this particular individual, she's not racing, she's actually, she's her only goal is to ride a bike in comfort and this reduction, this 15mm is a reduction in crank length has enabled that. Sounds quite short but it worked. Surely James, if you want to ride your bike as fast as possible, you want the longest lever for the most leverage possible. If you're a machine, not a soft squishing human being that has physiological limitations, I think that's kind of what people don't really understand. Yes, absolutely a longer crank will deliver more leverage but if you at top dead centre of your hips are so impinged that you can't deliver any power then that leverage is not really doing you a huge amount good. If you've got a tall individual, let's say some six foot two, they've got like an 80cm saddle height and they're riding 165mm cranks, the leverage element definitely starts to come into play because 165mm cranks is disproportionate. Think about it logically though, so if you've got a really small person, 155mm cranks isn't necessarily too wacky or kooky, likewise I just heard a reasonable amount of 180mm cranks as well. You've got a guy who's six foot seven, six foot eight, or 175mm cranks can feel too short. Now one of the ways that one of the things that we found with the crank length that's too short makes the rider feel as though they're spilling into the front of the bike. Now I don't necessarily understand why or know why but it's something that I found through questioning and testing things that when the crank length is too short riders actually have more pressure on their hands. So some of the more crank length can result in making shoulder issues, numb hands, all this kind of stuff as well. Experimentation is key, you've got to go about it in an informed manner because if you try, so a lot of people if they just try a different crank length, you've already emotionally invested in that purchase because you're not going to get a little take it off, get a refa. So most people fit a short crank, oh this feels amazing because they've spread all this money on it, so it has to feel amazing. Going about it in a comparative way, comparative testing. So this crank on the jig here is adjustable. This is something that we change in every single fit and if you're having a bike, it's one of the keys to fitting on a bike fit jig rather than fitting on a rider's bike because it allows us to make these changes very, very quickly and we can get feedback from the rider as to how it feels. We use this jig in every bike fit, book a fit with me or Andy and we'll be able to optimize crank length for you but like say it's done in every single bike fit but if you're looking for bike fit, I would encourage you to look for someone carrying out on jig but at the same time jig doesn't necessarily mean it's a good bike fit. That's great mate.