Poll: Crank length vs Inseam

[Louis]

This issue has come up recent on the forum (e.g. Sandy's climbing post) and I've been thinking recently about crank length and what's right for me. Most folks say that the longer your inseam the longer the crank. So,

1) What crank length do you typically use on your road bikes?
2) What is your inseam (pbh)?
3) Are you mostly a spinner or a masher?

Thanks
Louis

(A while back I think I asked a simlar question but without the inseam part...)

[soulspinner]

172.5 cranks, 85.5 cm inseam,75.3cm seat height, spinner. I dont have a fast twitch muscle in my body.

[Ray]

172.5 (comfortable on 170s also, but not on 175s)
86 cm pbh
spinner

[sellsworth]

1) 175s

2) 31 in (78.7 cm)

3) I am a masher.

I tried to be a spinner for a few years but alas I am not. My local climb is 2200' vertical and ranges from 3%-7% gradient. I used to climb it in a 39x24 on a regular basis hoping to develop my slow-twitch fibers. Apparently I don't have any of those though. Not too long ago I did the climb in a 39x15 and felt stronger than in the 39x24. I found that I had more explosive power on the lower gradients in the 39x15.

I just switched from 172.5 to 175 cranks. I feel better with them on them on the flats and during accerlations on the climbs. I also made the switch because my mtb and tandem have 175s and I figured that it is better to have the same on all bikes.

[Sheldon4209]

170 cranks, 82.5 pbh, 72 seat height, spinner

Last fall I went from 175 cranks on our tandem after 10 years to 170s. My wife (stoker) says that I have a smoother pedal stroke. We did a ride in Virginia last week and I don't think that the 170s have hurt our climbing (maybe helped) although there are many varables.

Sheldon4209

[christian]

Ditto Ray.

86cm PBH
172.5 cranks (can ride 170 no problem, have 175 on commuter but don't like)
Spinner

- Christian

[rnhood]

91 inseam, 175 cranks. Mash and love'm.

[Dr. Doofus]

whaddaheck

90
172.5
88-95 on flats, 80-90 on climbs

[weisan]

whaddaheck

90
172.5
88-95 on flats, 80-90 on climbs

Doofus, refrain from saying anything that will give away our advantage to the competition...

[scrooge]

I'm taking a risk and am trying some really long cranks. I haven't gotten them yet (coming with my new bike--hopefully next week), but if I remember correctly they are 200mm (built by Zinn). I have @ a 101 cm inseam, and it made some sense to me that if a person a half a foot shorter than me would use 175 or 180s, I could use 200s. Hopefully that wasn't a foolish choice. :confused:
Oh, and I would qualify my self as a spisher (but probably leaning on the masher side).

[csb]

86.96

172.5, all i've ever known

[musgravecycles]

ok I'll bite:

Inseam 93.6
Cranks 180mm

[mad_mark]

ok I'll bite:

Inseam 93.6
Cranks 180mm

What 180mm cranks do you use?

Mark, who is in need of a new set if he is ever allowed to commute again, let alone ride.

[musgravecycles]

What 180mm cranks do you use?


Campy Record

It's hard to find those long lengths unless you go record or dura-ace. I know some other crank specialists make them also (like TA) but they can be hard to find as well. An FSA rep told me at the show in Taipei a couple of years ago that they make a few 180's but don't advertise that they do, so give 'em a call and see what they've got.

[Too Tall]

Holy carp Scrooge..iszat right 101 PBH? Yowza. I'm choosing you first for kickball.

PBH - 97.5
Crank - 180 (road)
Crank - 175 (track)

Spinner. 90-95 avg. training 95-110 avg. racing

Send all apare 180's to me and William, we'll know what to do with 'em.

[William]

PBH: :confused: I don't remember. I'll measure when I get home.
Crank: 180 DA (though could likely go longer).
Spinasher/Mashinner

Send all apare 180's to me and William, we'll know what to do with 'em.

YES!!! Mark, please send them our way. ;)

William

[mad_mark]

Actually I have a set of 180mm TA cranks on my bench, they need a good home along with the 177.5mm Records keeping them company. Under pressure from the Mrs, the fleet is being downsized :argue:

[Sandy]

inseam- 1253 cm

cranks- 2000 mm-custom

Gerald Giraffe

[Sandy]

Inseam-12 cm

Cranks- 20mm-custom


William's Bassett Hound

[zap]

Inseam 88.219mm

Crank Length 175mm

Cadence somewhere around 80-85.

[scrooge]

[QUOTE=Too Tall]Holy carp Scrooge..iszat right 101 PBH? Yowza. I'm choosing you first for kickball.
[QUOTE]

Yep. No joke. I'm thinking about becoming a USCF registered racer so that I can give you (TT) a run for your money as the tallest one around. However, there is a guy lurking on this forum that I ran across who rides a 70cm Serotta, so maybe he'd have us both beat. :rolleyes:

William--when you say you think you could go longer than a 180, what leads you to that conclusion? Is this based primarily on your fantastic leg strength that I've been reading so much about, or is it something you can "feel" when you ride (like you want to make bigger circles, you just can't?)

[William]

It's a "feel" thing. I just feel like I could deal with more leverage. I don't know if I would like it, but I would like to try out longer cranks some time.

William

[David Kirk]

Inseam - 95.5

Crank - 180mm

I'm in the process of building up a new bike for myself and have a set of Zinn 190's that I'm excited to try. Anyone using Zinn's.

Dave

[Too Tall]

Madman, Do I have to beg? PM me brah. Mars needs spare 180 cranks.

Dave and anyone else contemplating really long cranks. How will this affect torso / thigh angle and is BB drop something you'd consider if designing a frame with very long cranks in mind? In my futzy adled sponge brain I'd want to steepen my STA at a minimum to maintain the same relationship I am used to or have I got this wrong?

[Sandy]

I once rode with a couple, both of whom had Zinn bikes, and Zinn cranks. He was probably about 6'-6' 2". She was not really tall. Her cranks were very long, and his dwarfed any that I have ever seen. I don't remember the length, but I was amazed. Both really liked the Zinn bicyles. They were mediocre cyclists at best (but both exceptionally nice).

Zinn's formula for crank length seems to generate really loooooong cranks. The formula is, as I assume that you know (as you know so much), crank length in mm = inseam length in mm x .21 for tall cyclists (this being a conservative formula). For you, at an inseam of 955 mm, that would yield a crank length of 955 x .21, which is 200.5 mm. That would be one loooong crank. I believe that he does cranks up to 220 mm.

By the way, your explanations on the forum are really both insightful and very clear, even to me. The tire pressures that use for your cycling are very striking,so much lower than most. At 180, you are not light for a cyclist, although reasonably light for someone your height. I am down to 120 r and 115 front, from 140 f and 145 r. But I weigh 210. Both are heading down- weight and psi. It seems at lower psi, the quality of the ride is better, the handling is better, and speed does not drop.

Not So Light Not So Fast But Very Cranky,

Serotta Sandy

[David Kirk]

Hey Too Tall -

Compared to my "normal" geometry based on 180mm cranks ( 72° seat angle and 8cm drop) I made the new bike with a steeper seat angle ( 72.5°) and with less drop (7cm).

Sandy - thanks so much for the kind words. I'm happy to hear you like my input and info. I'm not sure all do. I try to take a very pragmatic approach to this and there are many that want to believe the magazines and think that there is some black magic going on. I think there isn't.

As for crank length..........I know I don't have all the answers for sure but I am sure that the 170mm - 180mm range doesn't make sense and that there must be some workable relationship between leg length and crank length.

Way back in the day when I raced BMX for rent money I used 190's. I had no trouble spinning those things at all. I'm sure I'll have a few wierd weeks with the new 190's but it will be interesting at a minimum.

We'll see.

Dave

[scrooge]

Madman, Do I have to beg? PM me brah. Mars needs spare 180 cranks.

Dave and anyone else contemplating really long cranks. How will this affect torso / thigh angle and is BB drop something you'd consider if designing a frame with very long cranks in mind? In my futzy adled sponge brain I'd want to steepen my STA at a minimum to maintain the same relationship I am used to or have I got this wrong?

TT--I'm obviously no expert in frame design, but I know that my builder is raising the height of my bottom bracket fairly significantly. It has since occurred to me that I would like to know how this will affect the ride of my bike (from what I've read on the Riv website, I suspect my bike will feel somewhat less "stable," correct?), but that's another issue . . . As for STA, the bike is being built with a 72.25, though I'm not sure what role the crank length played in that decision.

Incidently, I did email Zinn himself and ask some of the same questions you did. His reply (which he hopefully won't mind me posting) follows:

"You will of course have to lower your saddle by the length difference. Generally, for someone of your size that's about all you have to do, since the other crank was too short for you and your knee was probably already further forward relative to the pedal than ideal. I generally see no reason to lower the handlebar, since your knees will be coming up higher, and the hip angle will tighten up if you do."

[dirtdigger88]

inseam 90.17 cm

cranks 175mm

spinner trying to be a masher or a masher comming out of the closet- all depends on how you want to look at it

Jason

[Too Tall]

This is interesting I'll be keen to see what you both find out. Hey, BMX'rs make great pro cyclists there's lots of em'.

[dirtdigger88]

Mr Kirk-

I can remember my BMX days- when I first went to 180mm cranks (I was about 12 years old or so) I remember banging them off the road a time or two before I was use to them- kinka amazing that we ran such long cranks back when we were kids yet now as adults- we would not consider it

Jason

[zap]

Ever see Robbie out handle Cipo. In the wet.

Must be something to BMX'ers.

[dirtdigger88]

I honestly think you are seeing better bike handlers out there today than in the past- not to say the greats were not fantastic in the handleing dept. but many of the up and commers have been racing BMX then MTB then finally Road- I seldom ride with people who dont comment that I must be a MTB rider- I think it is the jumps and wheelies that clue them in :p

jason

[Too Tall]

The reason BMX'rs run them huge cranks is leverage. Also, they are out of the saddle for almost the entire time.

[Elefantino]

Suddenly, I feel like shrimp. 101? 97? 93?

I'm 91.5, 180 (Record), Masher.

But enough about that. I'm wondering how you corner with 200 cranks, other than "carefully"

[zap]

You feel like a shrimp? I wonder if some are measuring while wearing heels?

[Rich_W]

86.0 inseam
77.5 saddle to bb (Keos)
78.0 saddle to bb (Deltas)
172.5 cranks

Masher and a Spinner

Grew up on BMX... 11 novice, 12 novice, 13 expert, 14 expert, 15 expert, 16 expert... 17 got a car and a girlfriend :cool:

Back in the days ruled by the 4130 Torker, Thruster Timmy Judge, GJS, PK Ripper and "The Sting"... JT Leathers, Vans, and a can of oven cleaner and metal polish to take all that colored anodizing off our parts!

[dirtdigger88]

Rich_W

Ah the memories- I had a "Sting" later I got an SE Quad- the pre cursor to flat land trick bikes!!!!! Learned to ride vert ramps on that one- Wore the checkered Vans and had the navy blue JT "leathers" I started racing a bit younger than you- I also discovered girls a bit quicker ;) - met a girl that lived across town from me- it took too long to ride to her house- so I got my first road bike-

jason

[Rich_W]

Holy Jeff Spicoli "That was my Skull" Checkerboard Vans?

Tight!

Any body here order a pizza?

[dirtdigger88]

the scary thing is that the 14 year ols kid who lives by me has discovered Vans- he just got the checker board slip ons- he was kinda bummed when he found out I had some of those is grade school!!!

Do you remember the elastic shoe strings they use to sell- that way if they got caught by your sproket- you wouldn't ripp off your shoe- What were we thinking!!!

Jason

[cycler48]

82.5 cm inseam
172.5 cranks
spinner

[dirtdigger88]

82.5 cm inseam
172.5 cranks
spinner

man- why are you trying to get back to the orginal topic- can't you see we are trying to get a tangent going here? some people have no respect for the insane

Jason