alfred mcdougal

Hello all. I'm 6'4" tall and ride Sugino XD2 175mm cranks. I like the Q factor on these cranks. These cranks work, but I'd like to try longer cranks. According to several measurements I have taken and a few recommended formulas to determine proportional crank length, I would be better off riding 190mm - 195mm cranks.

I found some custom manufacturers that sell cranks in the 185mm – 220mm range but they cost a fortune and I would probably have to get a new bottom bracket as well.

Does anyone know of a manufacturer who produces 190mm – 195mm square taper cranks that cost less than $150.00? I would prefer a wider Q factor like the XD2s if possible.

Thanks

Dubbayoo

I really don't think you need to go that long. Get some 180mm SRAM Rivals.

big john

Did you try Lennard Zinn? I know he writes about this stuff in Velonews and I think he makes custom cranks. I can't imagine it would be cheap, though.
Don't forget with 195 cranks your foot will be really close to the ground.

Shimagnolo

I used to think he made those cranks until someone posted a link to the company from which he gets them.
He just has them rebadged.

carpediemracing 

You can look at BMX cranks too, although I don't know how long they get. They have wider Q factors in general.

cdr

AnthonyG

Wait for Aussie531 to chime in

He's a tall guy who's gone through the same process and come back again. I'm a proponent of proportional length cranks but my interest is at the other end of the scale where short riders are always forced to ride cranks that are too long. Anyway if your basing your desire for longer cranks on the 21.6% of inseam figure then I think thats too long. It MAY work for some but I think its too long and prevents the rider from adopting a good aerodynamic position. I recommend that cranks should be in the RANGE of 19% to 20.5% of inseam. To me the 21.6% of inseam figure is both too restrictive and TOO long.

EDIT: Actually you can search for crank length and look for Aussie531's posts. We've discussed this many times.

Anthony

TommyL

I'll chime in. I had 180mm DA cranks on my Trek, but when I got my custom Curtlo built I thought I'd take the opportunity to try longer cranks. It was the number one thing that Doug, the builder, recomended when we began planning the bike. I went with 200mm cranks, 21% of my inseam.

It seemed weird at first. My spin seemed HUGE, but I quickly got used to it. Now when I ride the 175's on my single speed, it seems small, and like I have no power.

I've been doing some more climbing lately, and I think the longer cranks have helped a bit. It is easier for me to stay in the saddle and spin- I have never been able to make standing on the pedals work, aside from a few strokes of recovery.

Another weird effect (I'm not ready to call it a downside yet), is that my spin is slower. I have trouble keeping it up to 90rpms, and 70-80 is usually more comfortable. Then again, it feels more natural this way. I could do 90-95 on 170's or 180's, but I would quickly tire. I liken it to wen I ran cross country, and my stride was longer but slower than my shorter teammates.

Next time I get a bike? If it's a custom, I'll probably get 190's. I would also consider some Specialties TA Carmina 185's, which would give me a 19.7% of inseam. I definitely wouldn't want longer than what I have now.

Jynx

what is your inseam?

big john

TommyL, did he build the frame with the bottom bracket a lot higher than normal? Do you get toe overlap an the front wheel?

adriano 

that doesnt sound very good.

TommyL

94cm using the book in the crotch method.

Yes higher bottom bracket, and there is no overlap because the wheelbase is relatively long.

Maybe I should have been more specific. With the 180's and spinning at 95, I feel like I have no power relative to how tired I'm getting. When I slow it downa bit, I am able to maintain better.

Also, I don't have a cadence computer, I get these numbers from counting my rotations while watching ten seconds click by on my speedometer. They could be way off (either direction I suppose), so maybe I should have left it in in non-specific terms.

Hope that helps.

alfred mcdougal

Thank you for all the replies.

Yes, I have Zinn's site bookmarked. If I built a bike I would consider spending $400.00+ on cranks, but I am not.

I have thought about clearance issues. I am aware that with longer cranks, peddling through tight corners would have to be sacrificed. Not a problem, the cranks would be for a SS with a high bottom bracket shell, I rarely take super fast corners on my SS anyway.

I also have the SPECIALITES TA site bookmarked. I would prefer a wider Q-factor than the 75mm on offer.

In the end... it is impossible. I spent 4 hours yesterday searching and can't find a sub $375.00 option. I'll probably stick with the 175s until the drive train wears out. From there I have no choice but to spend a lot of money on a better fit. I hate being tall, the standardized machines don't fit.

TommyL

I got my 180 DAs on ebay. They fit on a factory bike. Keep your eyes peeled.

Also, if you eventually do go custom, you will probably realize that standardized machines fit better than you thought.

zzzwillzzz

well it is similar to running in that with the longer cranks your legs are traveling a lot further per revolution than with the short cranks so to have a similar leg speed to need to have a lower cadence. so with a 175 mm at 90 rpms is equal to 190 mm crank at 83 rpms. when you spin the long cranks at 90 it like using 175s at 97 rpms

jay0k

How can you ride 190mm+ cranks without a custom built frame? You're likely to be clipping the ground with the pedals frequently especially if you do any racing or hard turning.

531Aussie

Ha! I'm only 6ft, but I do have long legs: 35.25" inseam.

I'm trying to cut back my forum time, but I can't resist threads like this, especially ones asking about such long cranks

531Aussie

I'll try not to bore everyone by keeping this shorter than usual.

As I said, I'm 6ft with a 35.25" inseam. A few years ago I persisted with 180mm cranks for about 12 months (I even bought 3 sets of them for my 3 best bikes), but I ended up getting rid of them, and now use 172.5s. I ride no slower – and possibly faster -- with shorter cranks, and with no knee pain. I would've been happy to go back to 170s, but when I was 're-stocking' my bikes with shorter cranks, my local shop had more 172.5 DAs, and no 170s, so I took the 172.5s.

Firstly, long cranks impact more on position than they do on spin (unless the rider is a pure sprinter), which is something that I'm surprised gets overlooked. People think they can simply gain some extra leverage and power with long cranks, just as long as they can cope with a bit of a spin issue, but it's not that simple. For example, if someone gets 10mm longer cranks, then drops saddle the corresponding ~10mm for the extra reach at the bottom of the stroke, the pedals come up a whopping 20mm higher (relative to the rider) through the top of the circle. Being in a lower and weaker position, while trying to produce power through the downstrokes with larger hip and knee joint angles, makes long cranks harder to push. Relative to the top half of the downstroke -- which is where we get all our power -- It feels like you've simply dropped the saddle 20mm, and are hoping that the extra leverage will counter being in the weaker position.

That's the conundrum: there's more leverage, but they're harder to push because the rider is relative much lower, so it’s a bit of a wash. That’s why I gave them up (I also had some medial ligament pain which went away after I stopped using them).

My position became so screwed up with 180s that I was forced to try some 175s again, which felt much better (because I was higher over the pedals, so I could pound the crap out of them), so that was the beginning of the end for my 180s. I went back and forth between 180s and 175s for about a month, before finally getting rid of the long cranks.

I also found that my hamstrings were under a little more strain during 'red-line' efforts, perhaps due to the extra hip flexion, so kept lowering and lowering my seat, to the point where it felt as though my knees were in my chin at the start of each down-stroke.

So, there was the very frustrating feeling with my 180s of not being able to "get on top of" the pedals at the top of the downstroke to really pound the crap out of them. I'd sometimes have rides where I was constantly getting off the saddle to alleviate this annoyance.

There's also the issue of forward reach, which might not seem like much, but it's noticeable, and can be annoying. This may have contributed to my hamstring tightness and subsequent, repeated seat lowering, even though I moved the saddle forward

There's also a conundrum with torque and muscle force, which Arnie Baker explains much better than I can: https://www.arniebakercycling.com/han...arm_length.htm

I still have some 177.5s on one bike with which I occasioanally experiment, but I much prefer the 172.5s. I don't mind the 177.5s for off-the-saddle, short hill efforts, but if I spend any amount of time grinding on the saddle with these cranks, they start annoy me all over again.

Secondly, the “21.6% of inseam” is totally bogus, and gets me a bit cranky! It’s insane, especially for taller guys. It’s just one guy’s opinion (Kirby Palm), and he made it up to suit his own preferences, then Zinn jumped on it to suit his personal preferences, and to sell cranks.

Palm simply decided, just to suit his preferences, that, because there were a ‘certain number’ of riders with 31” inseams using 170mm cranks in the old days, this was the optimal ratio. That’s all it is! That’s where he got his oft-referenced, “magic”, “engineer-inspired”, dodgey ‘formula’. So what? There were also a zillion riders with 35” inseams using 170s, and a gazillion riders with 33” inseams using 172.5s. etc. What a crock! I could start a site saying that, because a large number of riders in the old days with 37” inseams used 170mm cranks, this then is the perfect ratio.

The 3 most prominent proponents of long cranks on the net -- Zinn, Kirby Palm and the ‘Thanks to My Cranks’ guy (his site has been down for ages) –- are all the same: they are all tall guys who were frustrated in the old days at the lack of cranks no longer than 175mm, so the sourced longer stuff, and went crazy with delite when they found what they were looking for. It snowballed from there.

The 21.6% of inseam thing would put me on 193mm cranks, which is so crazy I can’t even imagine it. I wish Palm would stop paying his server fee so that site would die.

I dunno how shorter guys ride on cranks longer than about 172.5. I have a theory that shorter guys are often weaker on flats, not because they are less powerful than bigger guys, but because they’re trying to push cranks which are way too long for them. Lots of shorter guys should be on 165s or shorter.

To rap up (I’m getting bored with my own thoughts ), no pro in the world, over about 5’9” is using cranks which are 21.6% of their inseam, yet they still all totally smash the crap out of us. Backstedt and Boonen use 177.5, but they’re both about 6’3”/6’4”. Ullrich also used 177.5s, but he’s 6ft. Indurain is 6’2”, and used 180s, and 190s for some time-trials. Considering Indurain is 2” taller than me, I’m gunna assume that his inseam is longer, or the same as mine (35.25”), which would still keep the 190s under 21.6%. His inseam would have to be 34.5” for 190s to be 21.6%, which is pretty short for someone 6’2”. And, ‘irregardless’, Indurain (and Ullrich) are two of the strongest ever riders! Sosenka reportedly used 192s for his hour record, but he’s 6’7”. Some claim that he used 200s, but it says on Bike Cult that he used 190s; and, anyway, 200 would still under 21.6% of his inseam. Pantani occasionally, reportedly, used 180s for mountain stages, but I remember him doing a lot of his climbing (especially attacking) off the saddle, which makes the position problem void. I don’t know of any current pro using 180s.

Thirdly, long cranks can hurt knees, because of force being applied with a sharper knee angle. I once hurt my knee in the late '90s when I jumped from 170s to 175s. This put me off long cranks for a long time. I also had some mild/moderate pain in both medials when I used the 180s.


'Fourthelelely', when I went back to shorter cranks, I had the strang sensation that I could ride at the same speeds with a lower heart rate, because the effort on shorter cranks was more of a 'short range stomp', rather than a longer range 'leg press', using muscles through a greater range of flexion.



To the original poster, I recommend getting some affordable 180s to try before spending big on anything longer.

More later….maybe.

531Aussie

I agree that longer cranks are much less impactful on, and sometimes useful for, riding in situtations where brief surges are what the rider is mostly doing, especially in races when the rider is planning on wheel-sucking for most of the race. When spending most of a race at sub-max efforts for short periods, the problems with long cranks and position aren't as 'severe'. Also, if the rider isn't planning any long-ish near-max, TT-type efforts, they could probably put their seat up a little higher to alleviate some of the problem of the extra knee and hip flexion.

TommyL

Thanks for the input Aussie, those are definitely things I will watch for!

dizzy101

Your post contains useful information, but I don't think it's reasonable to suggest that Zinn spreads misinformation just so he can make more money by selling cranks (which is what you're coming close to suggesting). That's quite a claim, and I have not seen any evidence for it.

You're 6 feet. That's not very tall. Zinn sells bikes and parts to folks who are 6'7" and up! The OP is 6'4". That's tall-ish. But again, it's not tall enough to need gear in the sizes that Zinn sells.

You bring up pros. Well, there aren't many pros who are 6'7" and up (except this Sosanka dude). So claims about the gear pros use is not very relevant to the question of what length crank people who are tall need.

(I'm 6'7" myself (mostly leg, pants inseam 39) and have always ridden 175s. I'll probably try 180 or 185 in the near future.)

531Aussie

(By the way, I haven't gone 'all out' with such a long post to try to debunk you, I'm just trying to be thorough)

Jee, that's pushing it. I don't think he's deliberately misleading anyone, because I suspect he believes it (the 21 to 21.6% of inseam formula) -- so I'd say it's not misinformation if he thinks it's true. But he does like referring to that guy's formula to help support his preferences and sell his cranks.....just sayin'....that's what he's doing.


That's one of the problems with the topic: there's no real definitive evidence either way. There are a couple of studies which suggest that very long cranks generate more leverage/power, but cycling is much more than just a maximal application of force (I stole that from Zimmerman ); it's about force, torque, oxygen consumption, fatigue minimisation, and relatively fast muscle firing rates (revs; reps, what ever ya wanna call it) over (often) long periods.

And as Arnie Baker explains in this link, while longer cranks may reduce power requirements for a given speed, muscle torque requirements are increased due to the larger circle. https://www.arniebakercycling.com/han...arm_length.htm

Zinn has been banging on about this (and trying on and off to prove it) for about 15 years (or more?), and still hasn't convinced the world; all the while, the planet's best riders have been smashing amazing feats on traditional crank lengths. Zinn admits his 1995/'96 study failed, and still hasn't managed to prove his theories over all this time. All he really has is the anecdotal evidence of himself and a few of his lanky mates, yet there's probably 50 bazillion more anecdotes of people riding great with 'normal' cranks.

What bugs me is the ridiculous 21.6% proportion. I can't, for the life of me, imagine being on 193mm cranks. Can you see yourself on 214mm cranks? Crikey! Proportion is obvious, but why so bloody long? It's just their (Zinn's and Palm's) opinion, based an 'observation' that "a heap of successful riders with 80cm inseams used 170mm cranks." As I said in the other post: so what? There have been a jazillion other successful riders with other inseasm lengths using other length cranks. I wish Zinn would just say that the 21% to 21.6% thing is his own opinion, rather than quoting the "Palm factor", as if it's based on ten tonnes of empirical data, and arrived at after years of lab tests



Why not? That's one on the major points. It's not just about very tall people, but all people, including those tall-ish. There may not be any 6'6+ pros currently, but there are plenty around 6'2/6'3 who, if Zinn had his way, would all be on (roughly) 195mm cranks, but they ain't. As I said, Zinn and his croanies have been on and on about this for many years, but all the tall pros are using cranks WELL under 21.6% of their inseam (unless they all have freakishly short legs).

Zinn may be proven right it 20 years -- who knows -- but in the mean time, I'd say he's being proven wrong.

If you're interested, this is Zinn's excuse why every pro in the world doesn't do as he says:

"I suspect it has less to do with testing and more to do with what is available from sponsors, what a rider has used in the past, and the inertia of tradition in the cycling industry and of professional racing managers, coaches and riders. The industry is devoted to selling product and making a profit, and offering a lot more crank lengths does not make economic sense, because the cost per crank goes up, and they would still sell very few lengths outside of the traditional 165-180mm range. Also, the old-school ideas of their directors sportif and coaches are hard to buck."

As you may guess, I don't buy it. Does anyone think if a rider believed that very long cranks would help him win a major pro race that an equipment sponsor or 'tradition' would stop them? There's a few crazy things out there being used by pros to get an advantage: what about eliptical chainrings? Then there's the whole drugs thing. Besides, some pros have used relatively long cranks over the years, for example, Marc Madiot (180s), Pantani on some mountains (180s), Anquetil apparently used 177.5s for a period, and David Millar apprently TTs with 180s (although he's 6'3.5), so it's not like it's a secret or total voodoo.

This is Zimmerman's counter to Zinn:

"Despite an increasing number of long femured (tall) competitors, you will see that 175mm is pretty much the longest crank, other than for time trials, that is used. I would not, as has often been suggested, put this to conservatism. On the contrary, the fierce competition and prizes of professional cycling are substantial and bring a willingness to quickly adopt what might appear to provide some form of advantage--- which more often than not is at best psychological. In a realm where high tech voodoo and strange science abound, I can't accept the arguments to the contrary.."
Here's another counter view:
https://www2.bsn.de/Cycling/cranks.html

Here's a slightly mroe progressive view with a good explanation, but still somewhat traditional.
https://www.bikefitting.com/English/Theory/Crank.aspx


Anyhoo, the whole topic (power, leverage, vs torque, revs, and O2, etc) is probably moot, because very long cranks effect the aero position of a rider, and if you ain't aero, you ain't nothing. It's very hard to get the upper body very low -- let alone breath properly -- when your things and knees are slamming into your chest. So, if someone generates an extra 30w with longer cranks, but increases upper body drag by 70w, coz they can't low, then it's a waste of time.

Moisture

Resurrecting this thread.

I spent quite a lot of time riding on cranks between 19-20% of my inseam (165,170,175mm) , 88cm inseam;

It seemed fine to me at first, but they made me feel like I was always restricted to a specific cadence and power output. Forcing myself out of this comfort zone, as I did often; seeking better performance, began to slowly cause impingement in my right knee.

I finally pulled the trigger on 190mm driveline crank arms (21.6% of my inseam)

The first time I tried them, I knew this was something I should have invested into a very long time ago. The extra length in the arms gave me a perfect range of motion, really helped open up my knees and hips, etc. But the biggest difference really was the flexibility I now had under a broad variety of cadences, I found it much easier to maintain a higher cadence while pushing lower gears, which really helped me with adapting a cadence that can be altered on the fly depending on how you feel. I really don't find myself changing gears so often because I'm content with pushing high gears at a lazy cadence when you're not hammering it. The response to input.. when you do hammer it though..

I realized, that regardless what your inseam is, this is the sort of range of motion that feels super ideal in the world of cycling.

woodcraft

Isn't that before you began cycling?

Good read, 'tho- thanks for resurrecting it.

AnthonyG

Well everyone to their own, yet I'm a short rider myself so I invoked 531Aussie on the matter because I knew that he was a tall rider and his experience was more relevant to the discussion.

Longer cranks can work for the very flexible but they make it hard for most people to get into a good aerodynamic position and hold it for an extended period of time. If your a professional team leader who always has a domestic to break the wind for them, or some freak that can get into an aero position when others can't, then good for you.

Moisture

My riding position is not what I would call aero whatsoever- with or without my 190mm cranks. Of anything I feel like they actually helped me get slightly lower because I'm not sacrificing power output or leg extension by getting away with a slightly lower saddle height.