I've been riding my '89 Schwinn Voyageur around of late loaded with four Ortleib panniers (~15 lbs empty), four gallons of water (32lbs), usual high school teacher supplies (10 - 20 lbs) plus the bike itself (33 lbs); an all up weight of around 90 lbs. This my usual training regime in preparation for a possible 2,000 + mile tour this summer. I have always used what the bike came with, 170 mm cranks. Seemed logical,; I'm only 5'6" with a 30" inseam.


Just recently I ungraded to 175mm cranks, wondering here why I didn't do this a long time ago. I'm not a high speed rider who "spins", I just mosey along ~10mph, especially on tour. Where I really notice the mechanical advantage of the slightly longer cranks is when pedalling that 80lb barge up hills and when cranking hard to to get going from a stop or to speed up. From an aging standpoint too (I'm 61) I do appreciate the greater range of motion my knees have to travel too.


Any thoughts?

Somewhere around age 40 I fitted my heavy, MTB-based commuter with much longer cranks They worked and still work well with my custom high gearing. I have always been a masher rather than a spinner. However, I turn 57 next month and have found my knees don't like mashing anymore, and the longer pedal travel can sometimes aggravate my hips. I have lowered the gearing on my other two bikes over the last year, but my MTB commuter already has a very low gearing range. I have serious thought of of refitting shorter cranks.

I don't remember exactly, but I think I went from 168 to 175mm cranks.

Even with the slight knee and hip aggravation I love having longer cranks....for now.

the bikes I own all have cranks that are either 172.5 or 175. Although Im not short, I've wondered if shorter (170 lets say) would be better for my more natural higher cadence.
Like you, Im not fast, and 10mph, 16 kph is more the upper limit of my usual avg speed over a day, often lower in mountains, but my skinny legs are not mashers, so a faster cadence than others like just works better for my knees.
The thing is that Ive never had the opportunity to try shorter cranks, and the 175 crankset on the bike that Ive spent the most on touring the last few years has been fine for me....so I dont see myself changing it just to try it out.
Maybe my cadence with the 175s is a bit slower instinctively than shorter ones, but I cant say I feel a diff between the 172.5 and 175....

whenever this topic comes up, I think unless someone has the unlikely opportunity to change out cranksets easily on the same bike, so that fit and everything is a constant, its probably not easy to get proper answers.

I know you dont use spd cleat shoes, but a few years ago, I moved my cleat position slightly that puts my foot more "centered" on the pedal , it was feeling like I was "tippy toeing" too much before, and this helped with getting more slower cadence torque into the pedal....dont know if that is explained properly, but this may have helped with the 175 cranks Ive used a lot lately.
Also, I dont have a cadence reader thingee, so the times I have figured out my cadence for an idea, it was while touring, usually going up a long hill, and just counting for 30 secs or a min, just for something to do, and for climbing with a heavy bike, 80 rpm is about what my legs prefer, maybe 85, just less torque on the knees.

If your knees don't protest after a really long mileage day using 175mm, that is great. But keep in mind if you overstress your knees just a bit, that can make the rest of your long tour a lot less enjoyable.

I no longer stand on the pedals to power up hills or to accelerate from a light that turned green. I stay in the saddle and gear down, my knees are much happier that way. My knees are four years older than your knees are.

Until recently Nashbar USED to offer their own $60 ISIS mountain bike triple crankset (44-32-22), when they did it came in 170mm and 175mm options. Over the last five years I put two of the 175mm versions on mountain bikes I own and one of the 170mm versions on my Voyageur. I just switched out the 170mm cranksets with the lightly used 175mm one on my wall hanger mountain bike.

Sure glad I had that extra one handy, triple cranksets have suddenly become scarce. ISIS cranksets even more so. Why that matters is that two years ago I put a $150 SKF bottom bracket on that Voyageur, ISIS to fit the budget Nashbar crankset, according to SKF that BB has nine year's worth of use left on it, at least.

With respect to the crank issue 5mm of added crank length makes a surprisingly big difference.

Put M730 180s on my touring bike , I am a goldilocks, gear ratio , modrest cadence, slow , 10mph riding Cyclist..

BB just high enough to not drag toe clips when pedal upside down..

transferred them to my WTR.. initially,, for the sense of more setback when seatpost had none..


I have a variety , 170, 172.5, 175 & 180.. did not notice on tour with the 180, only notice as I go back & forth 170 to 180 on the same day..



...

Good point, but longer cranks don't have to be stood on to benefit from the greater leverage/torque they afford. For the last 18 months this has been my daily ride, a worked-over '95 Hard Rock, with the 175mm cranks....



It's great urban commuter bike, but just doesn't seem to roll as easily as my Voyageur, which is a high mileage-eating machine, maybe the wide-rim wheels I had built along with those stout 2" Marathon Plus Tour tires are too heavy.

When I got back on the Voyageur after a year and a half, the short cranks just felt confining and inefficient.

Im genuinely interested in your question, I do wonder though if the diff size/shape/seat to bars to pedals setup of your two bikes would be a factor.
To me, it would stand to reason that if you set the seat back on the voyageur, it could feel better (essentially putting your legs hips further back from pedals, , maybe replicating the 175 position ish.......lots of variables I wonder if are a factor.

tahts what I meant that it would be neat to try out on same bike the setups of diff cranks, with some time to fine tune seat position etc, to see if your assessment would still stand up or be the same to other riders also.

Off topic, but if that was my Brooks, I would tighten up the adjuster a bit and apply some Proofide to increase water resistance.

That is a nice looking bike, but the Marathon Plus tires have a reputation for being slow. Not because they are heavy, they just have a lot of rolling resistance. I have toured on Marathon Extreme 57mm wide tires (now discontinued) and they rolled better than I expected, they had a supple sidewall and did not consume a lot of energy when rolling. For a tire designed for rough roads and gravel, I was surprised how well they rolled on smooth pavement.

The bike in the photo has the 57mm wide Marathon Extremes. A third of my trip was on rough gravel (or rock), thus my choice of tire, but two thirds of my trip was on good quality pavement, thus I wanted a tire without a lot of rolling resistance.

you know, the more I think about it, I think that on my bikes with 175 cranks, I probably tend to spin a bit slower compared to my faster bike that has 172.5 on it. I realize my touring bike 175 is generally used with 40+lbs of stuff on it, and the faster bike 172.5 is used with hardly anything on it, and often riding hard and fast---but I do suspect that the longer cranks help with pushing a heavy bike along, as each pedal stroke generally takes more effort throughout the stroke.

again, I dont know if this is all in our heads, and I'd love to be able to do a back to back switcheroo on the same bike, same day, to really be able to see if we could feel a difference.
I still suspect that we adjust our "natural feeling" cadence for whatever setup to a certain extent, and I also suspect that unless someone is really short, or really tall, the differences are pretty small.

Thanks for the heads-up, I did notice it had grown softer and more droopier that the much higher mileage Brook's B17 on my Voyageur but hadn't thought much of it.

I can pretty much guarantee it isn't. Once a week, most weeks I ride with an evening "Social Ride" downtown, impromptu sprints on this ride are common. I unload the bike of all the panniers for this ride. When I sprinted a couple of weeks ago on the Voyageur I keenly felt the difference with the shorter cranks, and ironically I stood up in the saddle to try and make up the difference. Same bike this week, 5mm longer cranks, different ballgame.

The circumference of the circle described by the 175mm cranks is only about 3% longer than the 170mm crank, sure does feel different to me though.

I like my 180's, but can't seem to find them with all chainring combos. In particular, I'm not sure if I've ever found 110/112 BCD 5-arm Campagnolo Carbon cranks in 180 BCD.

Anyway, I had 172.5 cranks on my old bike for many years, but now mostly have either 175 or 180 cranks on all of my bikes, and I hardly notice the difference between them when riding.

As far as leverage. There is a trade-off. More leverage, but also longer circle (and thus lower cadence)... so no "free power".

Even though I rarely stretch, I am reasonably flexible, so the cranks work well.

One thing, however, I've had the battle of the bulge... not huge... but a bit of a bulge. And, longer cranks limit the ability to do a tight tuck without the knees/thighs whacking the stomach. Thus, 175's on any "TT" style bike. And, definitely nothing longer than 180's.

I have never had anything other than 175, so I have nothing on the crank length talk. However, If your knees are having issues, practicing resting squats is very helpful for strengthening the knees up. Spending upwards of 30 minutes a day and most peoples knees feel much stronger and capable of handling more.

Some are rather sensitive to crank arm length. Some find this out early and others are late to that party. I was an early bird. At 5'6" I have found 170s to be right. I've tried 175s a few times on personal bikes (either used road bikes or a few mountain bikes) but never felt right on them. So to with the 165s that are common on "real" track bikes and many 1970s 3 speeds. Now all my bikes (well, not the Monty trial bike) have 170s on them. All 10 that I ride somewhat routinely. As such I have some odd cranks on my shelves. Andy

my winter commuter is an old mtb with mtb tires on it. It has a 12-25 cassette on it, but the front shifter has been dodgey the last few years, but just havent been bothered fiddling with it, as I just stay in the mid ring all the time and tend to ride slower anyway on snow and whatnot.

The connection to the topic is that on the downhills I hit on my commute, Im in the 32/12, or only 70 gear inches, and I spin it regularly up to my max, which is I dunno, 110-120. The bike computer stopped working a few years ago also, so I dont know how fast I get up to, probably 35k or so, but I do realize that I guess I am not particularly bothered by the 175s, as I can happily spin them pretty well and it doesnt feel overly weird or anything.

thats interesting, and pretty much conclusive then isnt it? If it feels better, then thats all that matters.
I assume you didnt move the seat in the rails at all right? That would mean your feet are that 5mm further forward, and less bend in your knee with each rotation also then.
This kinda touches on the whole "fore/aft seat position" thing vis a vis the bend in our knees-which I figure is also a factor in how a bike "feels" for our knees. For sure, too forward and we risk "overbending", which isnt good for knees.

It's essentially like making all of your gears 2.8% lower. Depending on your gear spacing, each gear will generally be 10-15% apart from one another. 2.8% is one-third of a gear at best, probably closer to one-fourth or one-fifth of a gear. It's just enough to make a difference, but not a big difference. But if the extra motion doesn't bother you, why not?

The size of your tires also has an effect on your gear ratios. Wider tires stick out from the rim more, giving your tire a larger circumference and raising your gear ratios. Going from a 700 x 38 tire to a 700 x 32 tire will lower your gear ratios by almost the same amount as going from a 170 mm to 175 mm crankarm.

I'm a short guy, so I'm sticking to 170 mm. Anything larger would probably bother my knees or other joints. If I want lower gears, I'll get lower gears.

I run a 22 tooth granny with a 36-tooth big cog in back, but even so I know from experience that four or five miles of unremitting 7 - 9 % grades on a 75 lb bicycle will have me wishing for another 2.8%. I guess I'm not a very strong rider.

But more than simple ratios, there's gotta be complex issues of internal musculature and anatomy involved, in my case climbing with 175mm cranks just feels easier, and more than 2.8% easier.

90 lbs? Yikes. Tell me you are going to tour with less?

Crossing East Texas and Arkansas in the second half of June in '16 I arrived at a ratio of ~10 miles per 24oz water bottle and I had four, so I was carrying 40 miles of water which weighed 6 pounds. Would possibly need more than that out West.


Four Ortleib panniers, a surprisingly heavy 15lbs, but they last forever.


Bike weighs 33 pounds with front and rear racks.


Plus 20 pounds of tools pump, folding tire, camping stuff clothes etc.

Adds up to ~75 lbs.


Riding west in summer would mean going against prevailing winds during the hottest and driest time of year, all the while facing the afternoon sun. Sixty miles between accessible water is possible in some places.


So add two gallons (16lbs) water insurance ~90 pounds.


Maybe I'm a pessimist or a worrier, but hey I was a Boy Scout...... "Be Prepared"

Guessing TX is hot in June? Frying temps. Tried frame bags? They work well for me. I'm 235, with a Rigid Karate Monkey, plus 29er tires, so not light either. I like my big fork cages for carrying heavy stuff down low. My tours are in New England, so not as hot, more water. But some big mountains too, I " try " for 65 lbs or so, with food and water. Cheers.

had to look up what 24oz is in ml and its 700, so about a larger regular bike bottle.
One per hour when really really hot is just about the same as my experiences riding in hot weather.
I've never had to bike in places where I had to carry more than 4 litres, but can completely appreciate being prepared and carrying more for places you've been in, and your possible Death Valley trip.--but boy, water is heavy. But as you say, not having enough water sucks pretty badly, it aint fun and I certainly remember the few times its happened to me.

30 inch inseam and 5' 6" ... I would ride 170mm

No worries, I'll bring along the old crankset just in case, the crankarm puller thingimabob, a ratchet and some sockets, and a torque wrench

there's a good scout!