180mm crankset – baby step towards going big

Posted by SuperClydesdale on May 24, 2010 under Cranksets, Road Bike Components | 6 Comments to Read

Last week, I wrote that I am going big – big cranks to match my big legs.

I have not yet determined what length of crankset to go for, and since it’s an expensive experiment, I decided to try out different crank lengths by using an adjustable cransket.   Zinn Cycles rents these out for $50, plus a $500 security deposit.  This will allow me to try out varying crank lengths, without blindly picking a length, then being out anywhere from $370 (High Sierra Cycle Center) to $675 (Zinn) – note that custom cranks lengths are available from www.customcranks.de as well, and are priced from 170 Euros to 220 Euros.  The www.customcranks.de guys have some great looking cranksets, available in many colors and finishes.

In preparation for going big, I dug out an old Dura Ace 180mm cransket to begin to get accustomed to longer cranks.  I’ve had the 180mm crankset for a while, but didn’t really use it.  I went straight to a 175mm compact double on my S-Works, and put a triple on my Rocky Mountain.

2010 is the year of bigger gears, getting out of the saddle, strength building and other names for the regimen of self-flagellation that I have decided to submit to.  As a result, I have not been using the granny gear on my triple, and have not been riding the S-Works with the compact crankset.  For a big, heavy guy, abandoning triples and compact cranks is a huge move.   Really, it’s self-inflicted torture.  My legs are getting pretty cooked on nasty climbing rides, and while I know it’s all for the greater good, I also am hungry to take advantage of my long legs.   The 180mm crankset is the first of potentially several steps toward using a significantly longer crankset.

The flagellator

Should I buy this, and keep using my triple crankset? This would satisfy my sadomasochistic urges, but it won't improve my fitness level.

As I stated in my posting last week, 180mm appears to be the longest road crankset you can find from a major manufacturer (Shimano, Campy, SRAM, FSA, Ritchey, etc.).   And, even though manufacturers say that they make them, they are few and far between.  The only way I found my 180mm Dura Ace was to get an older model (7700), and I had to get it used on Craigslist.   When I say, “used,” I mean it looks like the guy was using it as a hammer.

When I went to look at it, I asked the guy, “What the hell have you been doing with this?

I used it!” was his reply.

Now, I don’t baby my bikes.  I ride them, and I put them in the back of friend’s trucks, put them on bike racks where they sometimes rub shoulders with other bikes.  But, I usually at least try to prop the bike up against something when I stop, and I almost always stop before I get off the bike and walk away.  I suspected that perhaps this guys had loaned his bike to Danny MacAskill.

By the way, if you’ve never heard of Danny MacAskill, or watched a video of him.  Stop reading this and do it.  Now.  Watch this, or this, or this.  He’s from a different planet.

So, I had a 180mm crankset, but it was so butt-ugly that I couldn’t bear to put it on my bike.  While some may argue the point, I do have some standards.   Now that I’ve decided I’m going big, I decided to invest some time in “restoring” the cransket.  I bought a bench-mount polisher, and removed about 99% of the scratches and gouges from the cransket.  Now, it’s highly polished, and it looks pretty cool.  Based on what I’ve read about refinishing cranksets, I decided not to clearcoat it because it will just show wear more easily.  So, no clearcoat, no Dura Ace decal, and no paint (I was thinking of painting it but couldn’t decide what color).  This is temporary anyway if I get the 190mm or 200mm crankset.  The biggest problem is – what will I do without that Dura Ace decal?  How will people know that I am a top-shelf kinda guy?  They might  think that I am riding with an Ultegra crankset, or (god forbid), a 105!!!   Since that won’t do, I used a Sharpie and I’ve clearly labeled these bad boys as Dura Ace, so that nobody will think I’m riding something less expensive.  That won’t do.

Oh yeah, I'm riding Dura Ace. Eat your heart out.

I’ve installed my cadence meter on the bike, so I can compare my cadence on the 180mm vs. the compact and the 177.5 that preceded it.   As of this writing (3 rides), I cannot notice any difference in my cadence.  In looking over my data, my cadence appears, on average, to be the same as it was with the 177.5mm compact.  While this is a very small number of rides from which to try to draw any conclusions, I don’t know that I will see any difference until I get into a substantially longer cransket (200mm and above) – I guess I’ll know soon.

I’ve been thinking (some might call it fantasizing) about the longer cranks.

One tantalizing possibility that is opened up by using longer cranks is to explore larger chain rings.  Imagine being able to use a 54 or (gasp!) a 55  instead of a 53!  I could really scorch down hills.  Those smaller riders had better wheel suck right behind me, or I’ll just pull away.   The effects of gravity combined with a 55-tooth big ring could be… impressive.

A splash of cold water on this long crank fantasy may be this — I have noticed a  potential red flag:  frame flex on my aluminum frame when using the 180mm crankset.  When I get up out of the saddle and really hammer it, I’ve been experiencing “ghost shifting” on all three of my test rides.   The bike shifts beautifully, even on steep climbs, but when I really crank hard for a rapid acceleration, it will shift around on the cassette.  My concern is that the longer crank arms are allowing me to exert more leverage on the frame, causing the frame to flex to the point of pulling the chain slightly off the correct cog on the cassette as I bear down.  I am now concerned that if I go even longer (I want to try all lengths between 190mm and 220mm in 5mm increments), that the frame flex will be even more exaggerated.  That could be bad, and may  mean that a longer crank arm requires a much stiffer frame.   Given that I have already broken three frames in my life, I am wondering if these longer cranks are going to put a lot more stress on a frame, particularly around the bottom bracket.

For those interested in exploring this route as well, the three manufacturers of custom (longer) cranksets that I am considering are:

If you are using a longer crankset (longer than 180mm), please share your thoughts and insights.

  • kingdavid said,

    Very interesting comment you made about the extra flex in the frame with the longer cranks. It makes a lot of sense that the flex will be greater. There is more leverage to bend everything.
    That’s why you need a stronger frame and wheels particularly. Just as when you put a bigger engine in your car, you need to toughen up other things like engine mounts, suspension, shocks, brakes, frame joists etc etc.
    I have had issues with 3 bikes I’ve owned in the last five years. You’ve got to have a really robust frame. Doesn’t have to be really heavy and clunky, just well designed. My present bike is an alu Opera Giogione with lovely bulky shaped tubes, shaped almost like bones!
    My Cannondale SystemSix is out the door because it’s nowhere near stiff enough.
    On that, in the last week, I recently ha the pleasure of trying out dozens of customer bikes which we had in a warehouse. One thing I noticed was watch out for aero frames! If they are not brilliantly executed, they can be very wallowy, wobbly and unstable. The ones I mention has a narrow frame and they were just awful. Some of the nicer ones were Scott, Specialized and I don’t remember them all.
    Personally, I’m going for the remarkable KHS FLITE 747 with 200mm cranks as standard. Can’t wait to post more about it once I’ve got it!

  • kingdavid said,

    Very interesting comment you made about the extra flex in the frame with the longer cranks. It makes a lot of sense that the flex will be greater. There is more leverage to bend everything.
    That’s why you need a stronger frame and wheels particularly. Just as when you put a bigger engine in your car, you need to toughen up other things like engine mounts, suspension, shocks, brakes, frame joists etc etc.
    I have had issues with 3 bikes I’ve owned in the last five years. You’ve got to have a really robust frame. Doesn’t have to be really heavy and clunky, just well designed. My present bike is an alu Opera Giogione with lovely bulky shaped tubes, shaped almost like bones!
    My Cannondale SystemSix is out the door because it’s nowhere near stiff enough.
    On that, in the last week, I recently ha the pleasure of trying out dozens of customer bikes which we had in a warehouse. One thing I noticed was watch out for aero frames! If they are not brilliantly executed, they can be very wallowy, wobbly and unstable. The ones I mention has a narrow frame and they were just awful. Some of the nicer ones were Scott, Specialized and I don’t remember them all.
    Personally, I’m going for the remarkable KHS FLITE 747 with 200mm cranks as standard. Can’t wait to post more about it once I’ve got it!

  • brendan montgomerie said,

    I am 6’6″ tall, and started riding in ’93 @ 245 lbs.
    I started using 180mm cranks in ’96, some cooks bros. Mtb cranks.
    These helped right away with no adaptation period.
    In ’09 I finally got my Zinn custom 200mm road cranks.
    I took a year to truly adapt. I have changed my diet and
    chiseled my weight down to my current weight of 170.
    I have a standard height bb height and did do some
    pedal striking in corners. I actually have to level my cranks when
    manuevering my bike while walking it around to keep the pedals
    from hitting the ground. Despite that adaptation phase,
    I noticed climbing speed increased right away.
    I am convinced the inability to pedal through tight corners is more than compensated for by the increase in acceleration out of corners.
    Miguel Indurain admitted after retirement to using
    190mm cranks throughout his tours. The frame flex issue I have read about is a non issue for me because my frame is a 2011 specialized
    s-works, on of the stiffest in the business.
    With the combination of correct crank length (20.5 inch femur)
    Stiff frame, and low body weight, I can now ride up the local
    3 mile climb in 12 minutes, which puts me at
    16th out of over 3000 on the strava leaderboard (tunnel rd, Berkeley ca). Basically I trained my ass of for years and years and still
    Couldn’t climb in double digits. I find that the cranks help me put out
    more power with a lower cadence and less fatigue, lower heartrate.
    It took a combination of proper sized cranks and
    seriously low weight, not years of hard training.
    I never had any knee pain adjusting to them, just a feeling of pedaling
    in huge awkward squares. I would say that for me the
    crank length increase added 2mph to my average climbing rate once I adjusted to them. My average cadence has dropped
    from 85 to 75, and that is not a problem because I have
    large quadriceps and ride saddle forward to take advantage of this.
    I use a 32spoke white industries hub for the rear which is a very
    stout hub with 379gram Kinlin niobium rim, Sapim spokes.
    I wouldn’t recommend the rim for those of you above 200lbs,
    but for the weight it is very strong and straight, for
    only about $35, xr-200. I got 5th last summer
    @ the mt. diablo hillclimb TT, with everybody
    who beat me being well under 6 feet and 150#s.
    If you have long legs, and want free speed,
    get longer cranks. And yeah, If you wanna
    really climb faster, you are gonna have to lose some serious weight,
    I am at my 13yo weight. Keep cranking guys,
    and don’t let anybody tell you proportionate
    cranks don’t make sense! They are just holding you back!

  • brendan montgomerie said,

    I am 6’6″ tall, and started riding in ’93 @ 245 lbs.
    I started using 180mm cranks in ’96, some cooks bros. Mtb cranks.
    These helped right away with no adaptation period.
    In ’09 I finally got my Zinn custom 200mm road cranks.
    I took a year to truly adapt. I have changed my diet and
    chiseled my weight down to my current weight of 170.
    I have a standard height bb height and did do some
    pedal striking in corners. I actually have to level my cranks when
    manuevering my bike while walking it around to keep the pedals
    from hitting the ground. Despite that adaptation phase,
    I noticed climbing speed increased right away.
    I am convinced the inability to pedal through tight corners is more than compensated for by the increase in acceleration out of corners.
    Miguel Indurain admitted after retirement to using
    190mm cranks throughout his tours. The frame flex issue I have read about is a non issue for me because my frame is a 2011 specialized
    s-works, on of the stiffest in the business.
    With the combination of correct crank length (20.5 inch femur)
    Stiff frame, and low body weight, I can now ride up the local
    3 mile climb in 12 minutes, which puts me at
    16th out of over 3000 on the strava leaderboard (tunnel rd, Berkeley ca). Basically I trained my ass of for years and years and still
    Couldn’t climb in double digits. I find that the cranks help me put out
    more power with a lower cadence and less fatigue, lower heartrate.
    It took a combination of proper sized cranks and
    seriously low weight, not years of hard training.
    I never had any knee pain adjusting to them, just a feeling of pedaling
    in huge awkward squares. I would say that for me the
    crank length increase added 2mph to my average climbing rate once I adjusted to them. My average cadence has dropped
    from 85 to 75, and that is not a problem because I have
    large quadriceps and ride saddle forward to take advantage of this.
    I use a 32spoke white industries hub for the rear which is a very
    stout hub with 379gram Kinlin niobium rim, Sapim spokes.
    I wouldn’t recommend the rim for those of you above 200lbs,
    but for the weight it is very strong and straight, for
    only about $35, xr-200. I got 5th last summer
    @ the mt. diablo hillclimb TT, with everybody
    who beat me being well under 6 feet and 150#s.
    If you have long legs, and want free speed,
    get longer cranks. And yeah, If you wanna
    really climb faster, you are gonna have to lose some serious weight,
    I am at my 13yo weight. Keep cranking guys,
    and don’t let anybody tell you proportionate
    cranks don’t make sense! They are just holding you back!

  • brendan montgomerie said,

    Devinci designs makes a 200mm you spider of choice crankset
    for around $220. They are 8 oz’s lighter than
    Zinn’s custom JIS cranks, but the Q-factor (stance) is
    something like 153 mm’s, compared to 147 with Zinn’s.
    I opted for the ZCJIS’s because I like JIS,
    they are heavy and very stiff, and the low Q gets
    you around corners without pedal strikes more easily.
    I believe 143mm’s is dura ace and nearly the lowest q.
    I think that 110 bcd cranks are less subject
    to ring flex. Heavier chainrings really helped me with that.
    That you are having ghost shifting makes me
    think you have a frame that is too weak for
    your power output. I have not experienced that
    self shifting even with a Reynolds trek from
    ’83 with gussets, my first RB, while I still weighed
    245! And at that time my lactate threshold was
    between 360-390 watts. I don’t know your weight
    or power, but I feel like something, or things, Is flexing
    way too much! TMI! Good luck with the cranks,
    I think they are very important, important enough
    to build a bike ” around” them. Start with the cranks
    and eliminate what doesn’t work with them.
    Also, Speedplay, BeBo, will help with cornering.
    Final TMI!

  • brendan montgomerie said,

    Devinci designs makes a 200mm you spider of choice crankset
    for around $220. They are 8 oz’s lighter than
    Zinn’s custom JIS cranks, but the Q-factor (stance) is
    something like 153 mm’s, compared to 147 with Zinn’s.
    I opted for the ZCJIS’s because I like JIS,
    they are heavy and very stiff, and the low Q gets
    you around corners without pedal strikes more easily.
    I believe 143mm’s is dura ace and nearly the lowest q.
    I think that 110 bcd cranks are less subject
    to ring flex. Heavier chainrings really helped me with that.
    That you are having ghost shifting makes me
    think you have a frame that is too weak for
    your power output. I have not experienced that
    self shifting even with a Reynolds trek from
    ’83 with gussets, my first RB, while I still weighed
    245! And at that time my lactate threshold was
    between 360-390 watts. I don’t know your weight
    or power, but I feel like something, or things, Is flexing
    way too much! TMI! Good luck with the cranks,
    I think they are very important, important enough
    to build a bike ” around” them. Start with the cranks
    and eliminate what doesn’t work with them.
    Also, Speedplay, BeBo, will help with cornering.
    Final TMI!

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