Thattalldude

Hi All,

Wondering if these hold up to clydes.

The HD version sites 285 lbs rider limit and come in long sizes, so they seem perfect for me. Pretty pricy but so are all the long cranks and these are carbon

So yah any info from big riders that have these would be great

I'm newb to posting here so let me know if I'm doing dumb stuff; see my post on the intro section for info on me, but here is a little: 36 yrs old, 6'5", 265 lbs...

Thanks,

Jesse

dr_lha

If you're below the weight limit you should be OK. Weight limits are usually conservative.

mbw

How common is it to use longer cranks like that? Wouldn't you have issues in the turns more easily?

I didn't realized people used more than 175mm cranks.

dr_lha

That's mainly because bike part manufacturers don't cater to the extreme ends of the market. If the OP is 6' 5'' and has long legs, longer cranks than the standard maximum are appropriate for fit.

mbw

Good to know. I am 6'2" and use 175mm. I have never tried anything larger.

vesteroid

Anecdotal at best here. I have been riding 175's for years. When I bought my new group this year, I bought a 177.5 crank. I have about a 1000 miles on it so far and dont think I would do it again. In some ways I like it, but others I do not. No matter what I seem to do to my seat height / set back, I cannot get over 95 rpm without some sort of bounce. I didnt have that issue on my 175.

Maybe I am still getting use to it, but I question all the talk about tall riders NEEDING longer cranks. I am 6'5" and doubt I buy this again.

Thattalldude

Some more info:

Do I "need" long cranks? No. I am hoping they improve my climbing; I can keep up with fast rider on the flats doing like 22 mph on my own all day long and closer to 30mph drafting if I am riding with guys that can do that, but as soon there is any kind of hill they gone in no time.

So I have this performance gap; on the flats I can hang with guys in much better shape then me on higend bikes, then on the hills it seems I get passed by almost everybody; even little kids.

I have a '77 65cm touringish 12spd bike that came with factory 165mm cranks; gearing is 52/34 14-32. I like it a lot, unless there is any big climb then I wish I was on any other bike I have. Getting out of the saddle is almost not an option. When I got on 175s that helped a lot.

I got a set of 180mm ird cranks for $100 a while back, liked them but I expected the difference to be a lot more noticeable. It's on a comfort hybrid keep at work so I only do short & fast rides on flats with it.

I also bought 180mm sram crankset at about the same time for my gt peace 9r, but the are still in the box.
I guess I'll get them on & do some big climbing to see if they help; that's really what I'm hoping for... But am expecting they aren't going to be noticeably larger (to me) like the other 180mm set.

So It seems like I might benefit from a bigger size like 185s or 190s (since I hardly feel the difference from 175s & 180s) I'm pretty sure I'm gunna go that route.

I really interested if the those extra long carbon cranks holdup to extra big guy's on them or if I should just go with aluminum?

Thanks for all the feedback, so far.

redtires

https://www.youtube.com/watch?v=wVeu5-BqbUE

Bicycle Crank Length

Even though I'm only 5' 9", crank length is something that I have been aware of for many years, ever since I worked with Lennard long ago. As someone who is nearly 6' 7" and with a physics background, I've never been disappointed in his theory's, nor his subsequent results. Here is some material that has a lot of good info!

adrien

On crank length, sure, give it a try. I have standard 175s on the road bike, 165s on the fixed gear (I'm almost 6'4). Reason for the 165s is that it's fixed, so you can't stop pedaling and you have to be weary of pedal strike when turning. I notice if I think about it, and generally it feels like a tighter engine, with less room to move around. Nothing wring with that.

On carbon, I personally have cracked or broken three carbon crank arms. My mech (a great one, btw) suggested enough already -- there are plenty of high-end alloy arms out there that are as light and strong. Right now I have the first generation SRAM Rival arms in silver, because I like the look. I'm likely to go Rotor on an incoming build.

Bill Kapaun

You have to find the best balance of what your knees will handle.
I've got a bad knee and have had to go to 165's to avoid pain and have a semi reasonable cadence.
I'm about 5'11"now, but used to push 6'1" in my "yute".
My results- length vs cadence-
175 60 foot was coming off the pedal in the 12 o'clock position.
170 80
165 85
160 80 Obviously there's a point of going too short. it kind of felt like being on a kids tricycle.

You lose "torque" with a shorter crank, but you make up the difference by spinning lower gears.
I've converted both my bikes to 3X9's and run 12-23 cassettes.
Lots of closely spaced gears to keep my cadence in a narrow range that works best for my knee & emphysema.
As I said, you have to find what works for YOU.

TrojanHorse

I'm forgetting their names but there are at least two people who build bikes with long cranks recently. I'm pretty sure BigFred did and I forget the other gentleman's name (he had a custom Gunnar built to accomodate large cranks)

Don't forget to take into account the bottom bracket height - custom bikes designed for longer cranks generally raise the BB a little higher. I also think SRAM makes an Apex crank in 180 if you just want to try out a less expensive version to see if you like the longer length.

vesteroid

you can get most any shimano or sram crank up to 180 at excel sports in stock,

Little Darwin

While I can see how longer cranks would help at lower RPM (which is why mtb cranks tend to be longer), I don't think that they will necessarily help as much as keeping your cadence up during a climb. The main issue hurting clydes in climbing is power to weight ratio. On the flats, riding the size/weight of the rider is not as highly relevant to the speed as it is during a climb.

If 2 riders are roughly equal as far as speed on the flats, one weighing 140 pounds, and the other 240 pounds, there is little doubt about who will be the better climber... no matter what crank lengths they use.

nfmisso

+1

And to expand; it is all about heart and lung capacity. Simplifying things a little a 142.5lbs bike and rider vs 285lbs bike and rider. The second combination requires TWICE as much power climbing as the lighter rider - ignoring aerodynamics for the moment. On the level, the bigger rider MIGHT need 10% more power than the smaller rider - which is not a big deal for the big person. But given human physiology, the bigger person is not going have a bunch more power (not force, power) than the littler person. Equipment makes very little difference in climbing - the mass being pulled/pushed up the hill is the most important factor. This is High School Physics, nothing more.

Drew Eckhardt 

The bigger person will make a lot more power assuming they got that way genetically not growing girth-wise because everything is larger including heart and lungs.

For a given body type and fitness level Watts/kg don't vary too much. At 3W/kg a 100kg rider is good for 300, versus just 210 for a 70 kg rider.

Climbing specialists' ectomorphic shape means that at low body fat a smaller fraction of our total isn't helping with cycling so we do a bit better; but even 4W/kg from a 63kg guy is just 250 Watts.

Sans 65+ pounds of middle age spread my chest measures 34" around without much room for lungs and I weigh under 140 pounds. After a year of easy riding to loose weight six weeks into my build phase I only manage 191W, and at my best after getting a power meter I never had a FTP over 235W. Although I levitate up hills when not fat, at 5'10" I have the aerodynamics of a barn door and keeping up with naturally larger riders on flat ground has always been a problem even when they're less fit than me.

late

Zinn Cycles::custom bicycle cranks :: extra Long bike cranks :: short bicycle cranks | Zinn Cycles website

Thattalldude

Done a couple good climbs (2000 ft, each) with sram x7 180mm crankset, and definitely seems easier climbing (going the same speed or faster).

They didn't feel like a big jump in size, but seems like additional muscle groups getting used and could easily go bigger.

So am thinking of putting this x7 on my aurora and for the gt peace getting a mr whirly 170mm crankset, and also 185mm arms since I can't get a full 185mm whirly crankset... Then do some climbs at each length (looks like they swap out easy) to quantify the perceived improvement.

RR3

I run 200mm Lightning carbon cranks on my Rando bike with Rotor 46-34 Q-Rings and the ceramic bearing upgrade.

I used to be a full clyde in the mid 200's but now just flirt with the weight cutoff.

All works fine.

What would you like to know?

No corner clearance issues since the frame was built for longer cranks. Yes, my climbing improved. My tailbone to floor measurement is 36.25" and my femur is a bit long proportionately although I am only a touch over 6'3"

brawlo

+1. Go and do some searching of @bigfred 's threads. He did a really good and thorough writeup about a new bike he was building with longer 195-200mm cranks and the subsequent adjustment to their length.

I'm 6'5" and ride 180s. I ride 175s on my track bike, and seeing as how that's my primary cycling love, my next bike will have 175 cranks to keep them similar. The is real leverage/gearing difference in using the 180s. If I wasn't so keen on track stuff, I'd be happy to look at 200mm-ish cranks, but they're just too different from my track bike.

bigfred 

My e-mail inbox has informed me that @TrohajHorse and Brawlo are attempting to draw me out of a recent Bikeforums hiatus.

I first adopted 180mm cranks over 25 years ago. I'd been curious about Zinn's proposal for longer cranks for a long time. And, finally, after finding a reasonably priced frame, tried them (@200mm).

They require adaptation. The jump from 180 to 200 requires your foot come 40mm higher at Top Dead Center. I had heard of people taking weeks and months of concerted drills to reach a degree of comfort with the change. I can confirm it took me a few weeks to feel as though I could use them effectively and months before I started to actually feel comfortable with them.

They make a difference. BUT, only if you're racing, riding timed sections or competing against the same group of riders on a regular basis. The difference is NOT night and day. It's on the grounds of 10% or less. I actually experienced a greater percieved difference on the flats than on the hills. That's not to say they didn't contribute just as much on climbs. Just that it wasn't as perceptible to me. I did start consistantly keeping up with or finishing climbs ahead of a couple guys I normally trailed. But, never did catch others that I would otherwise average the same as over a reasonably long ride.

Climbing is most deffinately about weight/power. Loosing 10kg will make a much larger difference in your climbing than the switch to longer cranks.

Lightnings are LIGHT. They won't make anything longer than 190mm in the HD model for clydes. (WEll, at least not if you're expecting them to offer their normal warranty:-) They are flexible. They are known for that. If you are concerned about longevity and durability, they should not be at the top of your list.

Sram offer Apex, Shimano DuraAce and Campy SR, in 180mm. Longer than that requires turning to IRD, High Sierra, Zinn, or in my case Andel. The Andels, in 200mm, with rings and BB weigh approx. 1300 grams! They are beefy. However, the stock rings are not particularly durable or stiff. I suffered a bent tooth on the big ring that required replacing. Others have reported simply flexing the big rings enough to cause rub and skip issues.

If you haven't found it already, here's a link to a thread on my long crank build: https://www.bikeforums.net/clydesdale...tto-build.html

I hope that provides some insight and is of some value to you.

Thattalldude

Thanks Fred; read your thread. Great info and about what I'm expecting and hoping for...

Zinn shows I should be on 190s to 200s (ish); I did 15minute test ride a khs 747 a few months back with 200s and my right knee had discomfort at the top of the stroke, probably from a bad strain I had some years ago... Anyway yeah they would take some getting use to if my knee wasn't an issue, so I'm thinking 190s might be the most I should do...

Also it's s weird no body posts how to compensate for cadence and gearing for crank length changes, so I'll put something up...