how many of you ride 170 vs 175 mm crank lengths? my new holzfellers are gonna be 170,should i have gotten 175? what is the benefit/difference between the two. obviously the 175 is longer and ur going to have more torque at your peak pedal but really how much difference does it make/feel??
crank lengths 175 vs 170
scottg07
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how many of you ride 170 vs 175 mm crank lengths? my new holzfellers are gonna be 170,should i have gotten 175? what is the benefit/difference between the two. obviously the 175 is longer and ur going to have more torque at your peak pedal but really how much difference does it make/feel??
Torque=radius x force. 5mm increase from 170 to 175mm is equal to a 3% increase in torque by choosing the longer crankarm (considering force is constant). It's likely not a significant gain to sacrifice better ground and rock clearance. I'd go with the 170mm for AM riding.
I can't tell the difference. I have 170 and 175 on my different bikes and can't tell what I'm riding on the trail. If you look at 5mm on a ruler, it is basically nothing. I don't understanad why it is such a big deal. They feel the same. If you didn't know ahead of time, you wouldn't know what you were on.
shortys
I switched to 170, partly due to a desire for exploration, partly because I got an 07 Superlight with a fairly low bottom bracket.
I feel a pretty big difference switching between the two lengths. I generally like the 170s better all around, but there is no doubt that I don't have quite the same level of torque/power at the upper limit. The upside is that my knees are happier; I shift a little more rather than try to grunt/mash my way through stuff. I think I "spin" a little more smoothly at "normal" RPMs too.
Bear in mind that I am relatively short-legged (30" pant inseam on 6'1") so long leggers might not feel the same way.
The good side of the 170s I hadn't thought of before trying it is that it is easier shifting weight from one outside pedal to the other when carving turns, and even cooler, when pedals are level, my feet are a little closer together, allowing me to bend my knees a little better and/or keep my body/shoulders more square to the bike. All in all, it was sorta similar to the effect when I relented and dropped my seat an inch or so down from "optimal" cross country height. Better handling all around at the expense of a little bit of ultimate performance.
I switched to 170, partly due to a desire for exploration, partly because I got an 07 Superlight with a fairly low bottom bracket.
I feel a pretty big difference switching between the two lengths. I generally like the 170s better all around, but there is no doubt that I don't have quite the same level of torque/power at the upper limit. The upside is that my knees are happier; I shift a little more rather than try to grunt/mash my way through stuff. I think I "spin" a little more smoothly at "normal" RPMs too.
Bear in mind that I am relatively short-legged (30" pant inseam on 6'1") so long leggers might not feel the same way.
The good side of the 170s I hadn't thought of before trying it is that it is easier shifting weight from one outside pedal to the other when carving turns, and even cooler, when pedals are level, my feet are a little closer together, allowing me to bend my knees a little better and/or keep my body/shoulders more square to the bike. All in all, it was sorta similar to the effect when I relented and dropped my seat an inch or so down from "optimal" cross country height. Better handling all around at the expense of a little bit of ultimate performance.
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175 to 170 to 180.
The 175's were fine for the type of riding I do. While trying to remove the crankset, the LBS found a manufacturing defect. The crankset got destroyed in the process and was replaced with 170mm crankset. I couldn't feel an immediate change in crankarm length but all forms of riding now required lots spinning... lots and lots of spinning. Log crossings and some of the more technical obstacles became more difficult while straight line riding seemed easier with lots of spinning of course. The LBS could not find a replacement 175 in time and offered to upgrade me to 180's. I am 6'2" and gladly jumped on the opportunity. Once again, it wasn't an immediate difference. I could not spin the 180's as smoothly as the 175's and certainly not the 170's but log crossing, difficult climbs, and technical obstacles seemed much easier. I eventually learned to spin better on the 180's but even after a year and a half, I am still not a smooth as I was on the 170's.
If I had to do it all over again, I would pick the 180mm crankset again. For around town or cyclocross, 170 or 175 would be best.
The 175's were fine for the type of riding I do. While trying to remove the crankset, the LBS found a manufacturing defect. The crankset got destroyed in the process and was replaced with 170mm crankset. I couldn't feel an immediate change in crankarm length but all forms of riding now required lots spinning... lots and lots of spinning. Log crossings and some of the more technical obstacles became more difficult while straight line riding seemed easier with lots of spinning of course. The LBS could not find a replacement 175 in time and offered to upgrade me to 180's. I am 6'2" and gladly jumped on the opportunity. Once again, it wasn't an immediate difference. I could not spin the 180's as smoothly as the 175's and certainly not the 170's but log crossing, difficult climbs, and technical obstacles seemed much easier. I eventually learned to spin better on the 180's but even after a year and a half, I am still not a smooth as I was on the 170's.
If I had to do it all over again, I would pick the 180mm crankset again. For around town or cyclocross, 170 or 175 would be best.
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I went from the usual 175 to 170 for 3 reasons:
1. The transition from HT to FS. I wanted the ground clearance, and I got it.
2. I'm average height but slightly less-than-average leg length. I wanted to try out how it would feel with shorter cranks.
3. I prefer to spin.
Of all these reasons I find #1 the most important one in making a decision, but it's not that much significant as I thought it to be. I'd say go with 175 mm.
That said, I thank myself for going to a 170 mm XTR crankset every time I clip something on the ground. )
1. The transition from HT to FS. I wanted the ground clearance, and I got it.
2. I'm average height but slightly less-than-average leg length. I wanted to try out how it would feel with shorter cranks.
3. I prefer to spin.
Of all these reasons I find #1 the most important one in making a decision, but it's not that much significant as I thought it to be. I'd say go with 175 mm.
That said, I thank myself for going to a 170 mm XTR crankset every time I clip something on the ground. )
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How tall are you? Whats your imseam? What kind of bike do you ride and what size is it?
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Then 175 mm would suit you better than 170 mm. That according to the established views, anyway ).
In other words, if I was 6 feet tall, I would have stayed away from 170 mm on a MTB.
In other words, if I was 6 feet tall, I would have stayed away from 170 mm on a MTB.
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Thank you! I can't believe there were 10 posts of nonsense before someone bothered to ask this question. It's like giving advice on pant size without asking how big someone's waist is. Yes, crank length is personal preference, but your leg size plays a big part in this.savagemann said:
OP: with a 30" inseam you could probably go either way. At 32" I'd say you want 175's. I'd try them and see what you think.
It's not just about the torque, it's about the position it puts your legs and knees in.
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But notice that the OP has only asked about 2 length options, and not extremely disparate ones. This can be understood as a leg size hint...kapusta said:
You see, I am used to creating heuristic algorithms that have to yield satisfactory results given incomplete data. I am also used to having a go at tasks that are poorly formulated, with no way to quickly obtain a more deterministic specification and a requirement that software must be created like, "yesterday" (or an answer given right away, for that matter). )
This routine, when reiterated over and over again, creates certain specialized workflow patterns, it seems. Patterns that are not easy to intercept and override before the pattern manager autonomously recognizes a task and engages a pattern to try and solve it. That must be mental reflexes in action. )
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I would just take the reciprocating mass divide then by the counteracting flow of suspension then multiply that by the pushingus factor which then gets deposited into the holder by the huffinupagainst flat function and go with the 170's. :thumbsup:
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There is no "one" answer to this. People making blanket statements are only stating what works for them. Generally riders fall into power-pedaler or spinner categories...generally. If one is a strong pedaler, one can generally benefit from longer cranks. But...you also have to consider the weight of the bike...the ground clearance...the rider physiology like leg length or even leg strength or injury...the terrain ridden...etc...etc. I'm 6 feet tall with a 32" inseam. I use 170mm cranks for my AM bikes. I'm also 57 years old with 57 year old knees, and I do spin instead of mash. The suggestion that 170mm cranks are only for DH bikes is ridiculous. Most people have just been programmed with the idea that 175mm cranks are the proper "normal". Other riders' needs and conditions may vary.
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