Saddle Height, Simplified

Saddle Height

Here’s a simple and reasonably accurate method for determining proper saddle height (SH). Depending upon how you prefer to do the math, it’s known as either the “Rivendell Method” or the “LeMond Method”. Regardless of what you call it, the results are essentially the same.

First you’ll need to determine your pubic bone height (PBH). You’ll need a wooden dowel* (something like a broom handle will do), a metric tape measure, and a helper. In bare feet, stand with your feet flat on the floor, 10″ apart. Place the dowel between your legs, and while pulling it upward with a force that approximates sitting on a saddle, have your helper measure the distance from the floor to the top of the dowel in centimeters. This measurement is your pubic bone height. To be sure you get an accurate reading, repeat the process a few times while making sure to keep the dowel level. Once you’re sure you have a good number, write it down or send it to yourself in an email so you have it for your next bike purchase.

Once you have your PBH, it’s simple to calculate your saddle height. Here’s the Rivendell math:

PBH – 10 to 10.5cm = SH

And the LeMond math:

PBH x .883 = SH

Let’s use my 88.5cm PBH as an example.

Rivendell: 88.5 – 10 to 10.5cm = 78.5cm-78.0cm.
LeMond: 88.5 x .883 = 78.15cm

I like the Rivendell math for its simplicity, but I like the LeMond math because it scales at the extremes. Either are accurate enough and will place you in a range that will give you plenty of power while sparing your knees.

Once you have your SH number, adjust your saddle to the proper height by measuring along the seat tube from the center of the bottom bracket (where the cranks bolt on) to the top of the saddle. Note that Rivendell recommends adjusting the math slightly for extreme crank lengths, but for the large majority of people riding either 170mm or 175mm cranks, these numbers are good.

There are number of other ways to determine saddle height, but I’ve gotten consistently good results using this simple, straightforward method. Enjoy!

Rivendell on PBH

*A wooden ruler or relatively thin hardbound book can be used in place of a dowel.

Park Tool N360 Installation and Adjustment Guide

Park Tool

Park Tool has posted a complete installation and adjustment guide for the NuVinci N360 hub on their website.

Park Tool

From the Archives: Bike Fitting is an Art, Not a Science

[Recently, I've received a number of questions about bike fit so I thought it would be worth re-posting this article from our archives. —ed.]

What counts in sizing and fitting a bike are the points where the bike intersects with the body. The relationships between the saddle contact point, pedals, and the handlebar grip area, determine the riding position. These relationships can be affected by a number of factors including frame size, saddle adjustment, crank length, stem size and adjustment, and handlebar design.

I’ve learned through many years of riding that, for me, the most important factor in bike fit is handlebar height in relation to saddle height (after setting saddle height, of course). I prefer the primary grip area of the handlebar to be at or slightly above the top of the saddle, when the saddle is adjusted to the proper height (more on saddle adjustment here). Too low and there’s too much weight on my arms, too high and there’s too much weight on the saddle. This is a personal preference based upon how I ride, and others will certainly come to different conclusions based upon their physique and riding style.

What I find less important is the length of the cockpit, or in other words, the horizontal distance from the saddle to the handlebar. If the saddle to handlebar height relationship is correct, I feel equally comfortable on bikes of different lengths (within a reasonable range). Consider the photo above. The Surly LHT is a 56cm frame and the Rivendell Sam Hillborne is a 60cm frame. As you can see, the Rivendell is longer, but because the bars are at my favored height, I still find it comfortable. In fact, these two bikes both fit me quite well for how I use them. The Surly is a city bike for hauling weight in traffic, and its shorter front is good for that type of riding. The Rivendell, on the other hand, has a more open cockpit and the stretched out position is better for longer rides on open roads.

Where it gets tricky is when you start looking at different handlebars, stems, and top tube angles. When I purchased my Rivendell, I knew from the start that I wanted to spec the bike with Moustache handlebars. These bars have much less rise (they actually drop a bit) than the North Road bars on the Surly. To get the grip area at or above the saddle, I knew I had to either use a stem with an extreme amount of rise or choose a larger frame to bring the front end of the bike higher. Since I didn’t want an exorbitant amount of stem showing above the headset, and I also wanted a more open cockpit than on the city bike, I went with the larger frame. On the other hand, if I had planned on speccing Albatross or North Road bars, I would have gone with a smaller frame size because of the handlebar’s greater rise.

Some modern sizing methods use upper body measurements and top tube length to determine frame size. While this may work for some people (but usually only if they’re speccing drop bars), it invariably places me on a bike that is too small. One of my bikes is a 54cm and it was sized using the top tube method. I’ve never been able to get the handlebars at my preferred height in relation to the saddle on that bike. The bars are too low and the cockpit is cramped, even though according to a popular “scientific” sizing method, this is the correct frame size.

All of this is a long-winded way of saying bike sizing is complex and I don’t believe it can be boiled down to a codified method. The photo above demonstrates that with careful component choices it’s possible to achieve similar riding positions on bikes of widely differing sizes. The number of variables in the process, including the intended use of the bike, frame geometry, saddle set-back, and handlebar/stem choice, make the process more an art than a science. Seeking out a knowledgeable salesperson or builder who has experience with transportation bikes, clearly understanding and stating your personal preferences, and remaining flexible in your assumptions, is much more likely to land you a properly sized bike than any mathematical formula.

Civia Commuter Remix

Civia Bryant
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Earlier this year, I made the decision to sell my Surly Long Haul Trucker and purchase a replacement primary commuting bike. Besides wanting to go to a low maintenance drivetrain with an internal gear hub and belt drive, I figured building (or rebuilding in this case) a new commuter would be a fun project for both me and our readers. I ended up purchasing a Civia Bryant Belt Alfine back in March and this article outlines some of the changes I’ve made to the bike since then.

From the start, this bike was intended to be a test bed for new parts. I started with a stock 2010 model-year build. It was a very nice bike straight out of the box, though I initially added a pair of Civia Market alloy fenders, a Pass & Stow porteur rack, a Tubus Logo rear rack, and a Pletscher double-legged kickstand. I also swapped the stock BB5 disc brake calipers for a set of BB7 calipers. The Civia could have easily kept me happy in this initial incarnation, but I already had other plans in the works.

Civia Bryant

The Drivetrain

Upgrading the drivetrain was the most significant and technically challenging portion of the remix. It involved two separate, but related, efforts: swapping the stock Alfine 8 internal gear hub (IGH) for a new Alfine 11 IGH; and, swapping the stock Gates CDX belt and pulleys for a new Gates CenterTrack (CT) belt and pulleys.

Civia Bryant
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Swapping the hubs presented a pair of challenges. The cassette joint (the part on the drive side of the hub to which the cable connects) on the Alfine 11 is significantly longer than on the Alfine 8. Because the cable stop on the Civia’s chainstay is designed for the shorter 8-speed cassette joint, the housing run between the cassette joint and the stop on the chainstay is very short with the 11-speed installed. This makes it a little more difficult to install the belt and rear wheel. It’s not a deal breaker, but it’s something to be aware of if you’re planning a similar upgrade. On bikes with either Paragon-style sliding/vertical dropouts, full housing runs from shifter to hub, or cable stops further forward on the chainstay, this is a non-issue.

Civia Bryant
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The other challenge was that Shimano swapped the rotational direction of the cassette joint on the 11-speed. The result is that the Versa VRS-11 shifter designed for the Alfine 11 shifts in reverse. On the 8-speed, the large lever was used to shift to higher gears and the small lever was used to shift down. On the new hub with the new shifter, the small lever is used to shift to higher gears and the large lever is used to shift down. While this doesn’t bother me on a thumbshifter, I found it disconcerting enough on the Versa VRS-11 to switch to a different shifter (more on this later).

The most critical aspect of installing a belt drive is getting spot-on alignment between the front and rear pulleys. Belt drives are much less forgiving in this regard than conventional chain drives. That said, a perfect belt line is certainly achievable, and once the drive is set-up properly, it’s truly a set-it-and-forget-it system.

Civia Bryant
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In the case of my upgrade, I replaced both the front and rear pulleys as well as the crank and bottom bracket. My existing crank was a 4-bolt 104BCD Civia, but CenterTrack pulleys are not available in that size (for the time being), so I opted for a Shimano Alfine crank and matching Hollowtech II bottom bracket (the BB is included with the crank). This combination represented my best chance of achieving a good belt line with minimal fuss. The bottom bracket and crank were direct bolt-on parts, and I’m happy to report, getting a perfect belt line with this set-up was not difficult. I installed the bottom bracket in the Civia’s 68mm shell without spacers, and with the CT pulley installed on the inside of the spider with the logos facing toward the frame (the CT pulley is asymmetrical), the front and rear pulleys are aligned to within 1mm, with approximately 2-3mm of clearance at the chainstay.

Civia Bryant
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In the process, I ended up removing the Civia’s belt guard. The guard mounts under the drive side bottom bracket cup and installing it would put the belt out of alignment 1-2mm. In my opinion, a guard is unnecessary with a belt drive anyway. I’ve tried my best to catch my pants in every belt drive bike I’ve ridden, and I’ve never been able to do it. After two weeks on this bike in street clothes, I can safely say it’s a non-issue.

Civia Bryant
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So, how does it ride? It love it. The biggest improvements from my perspective are the closer and more evenly spaced gears, the smaller number of mis-shifts when compared to the Alfine 8 (essentially zero), and the generally smoother and quieter operation (I didn’t think a drivetrain could be quieter than the Alfine 8/Gates CDX, but this one is quieter and smoother to the point of qualifying as “silent”). Because I’m in Northern California, I won’t be able to report on the snow and ice clearing capabilities of the CT belt and pulleys, but I do like the fact that rear wheel alignment (not to be confused with pulley alignment) on the CT drivetrain appears to be less critical than with Gates’ older pulleys and belts.

This wasn’t an inexpensive upgrade, and as you can see, it wasn’t without its challenges. Most of the issues I ran into would be non-existent on a new production bike. There are a few Alfine 11/Gates CT bikes available this year, and it looks as if quite a few more are coming out in 2012. Whether a major aftermarket upgrade such as this is worth the cost and effort will depend upon the individual. Even though I don’t at all regret undertaking the project, for many, selling an existing bike and replacing it with a dialed-in Alfine 11/CT production bike may be a better option.

The Cockpit

The Civia Bryant is one of the few production bikes on the market that comes spec’d with both drop bars and an internal gear hub. This was one of the reasons I was initially attracted to this bike. I’ve enjoyed drop bars in the past and I was looking forward to trying them again on the Civia in combination with the IGH and belt drive. It was a fun experiment, but after commuting with drops on a daily basis for the past few months, I’ve switched back to a set of 50 degree Civia Aldrich flat bars (these are the same bars I had on my Surly LHT before I sold it).

Civia Bryant
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There were a few issues that led to the change, the most troublesome being that, as outfitted with a tall stem and Versa levers, the bike wouldn’t fit into our City bike lockers without a wrestling match. I’ve also been carrying more weight on the front rack and I found myself wishing for less reach and more leverage than was provided by the drops bars. And finally, I wasn’t happy with the new Versa VRS-11 shifter in combination with the “reverse” shifting Alfine 11 hub. This may be a non-issue for most people, but I could not get used to using the small lever for upshifts and the large lever for downshifts. This ended up being the straw that precipitated the cockpit revamp.

Civia Bryant
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The cockpit upgrade included swapping the stem, handlebars, shifter, and levers. The stock stem had a 26.0 clamp diameter designed for drop bars, so I replaced it with an equivalent Civia stem with a 25.4mm clamp designed for flat/city bars. As mentioned above, the handlebar is Civia’s 50-degree Aldrich which is one of my favorite flat bars (the 50-degree sweep falls naturally under my hands). The shifter is the Shimano Alfine 11-speed designed for use with the Alfine 11 hub. And finally, the brake levers are Paul’s “Canti Levers” designed for use with road brakes. These levers are a particularly good match for Avid BB7 “road” disc calipers. They seem to have just the right pull ratio to take best advantage of the BB7, providing plenty of mechanical advantage while locking the brake well before the lever reaches the bar.

The Lighting System

No year-round commuter bike is complete without lights, and no commuter bike is more of a car replacement than one outfitted with an always-available dynamo-powered lighting system. In the past, I’ve owned bikes with dynamo systems, but in recent years I’ve relied mostly on battery-powered LED lights and rechargeable batteries. This is mostly due to the fact that we have so many bikes coming and going that it makes sense to use removable lights, but it’s also because I’ve been waiting for LED’s to fully make their way into the dynamo world.

Civia Bryant
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Civia Bryant
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With this bike I decided the time was right, so I installed an Alfine dynamo hub and Supernova E3 Pro headlight and E3 tail light. I’m going to save the full light review for another time, but I can say that it’s an awesome set-up that’s making me anxious for the dark-thirty commutes of fall and winter.

Civia Bryant
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Civia Bryant
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Conclusion

I’d say these upgrades were a great success. Most notable for me in my circumstances are the better gear ratios, the simplified oil bath hub maintenance, the more appropriate cockpit for multi-modal commuting and cargo hauling, and the always-available lighting. The upgrades weren’t cheap, and the technical hurdles certainly weren’t for the faint of heart, but at least for me, the results justify the effort.

Overall, I’m quite pleased with the Civia in its current incarnation. With its fenders, internal gear hub, belt drive, and disc brakes, the bike is all-weather friendly and should require very minimal ongoing maintenance. Plus, it can haul significant loads with its heavy duty front and rear chromoly racks and double-legged centerstand. With the addition of the dynamo lighting system, it may be the most commute-ready car-replacement I’ve owned to date.

Specifications

Disclosure: Civia and Gates are sponsors of this website and provided assistance with the drivetrain upgrade.

Note: For those who were wondering, all of the original parts taken off of the Civia will either be donated, sold, or re-purposed in some way. Very little goes to waste here… :-)

Shimano Alfine 11 / Gates CenterTrack Progress Report

For those who have been following my drivetrain upgrade project, I made good progress this week. The Alfine 11 internal gear hub and Gates CenterTrack belt drive are installed and everything is running smoothly. I’ve also totally revamped the cockpit (more on that later) and I’m working on setting up a dynamo lighting system. I’ll have a full report on the Bryant “makeover” next week once the lights are installed. In the meantime, here are a few photos.

Gates CenterTrack
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Gates CenterTrack
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Gates CenterTrack
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Gates CenterTrack
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Gates CenterTrack
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Gates CenterTrack
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Go Big

I have a suspicion that many people would enjoy their bikes more if they went to slightly larger cross-section tires and ran them at lower pressures than what they’re accustomed to. I typically ride at least 32mm tires for commuting and general utility riding, and I’ll often go up to over 40mm. Of course, the clearance around the fork and chainstays, as well as rim width, place limits on tire size. But still, I often see relatively narrow tires mounted on bikes that would accept wider rubber. And there’s nothing that says you have to pump your tires to the max pressure listed on the sidewall. I’ll often run my tires at 20% under the recommended max pressure to soften the ride; you’d be amazed how much this improves the comfort of any bike. If you’re running small cross-section, high pressure tires, you might be pleasantly surprised by the improvement in ride quality you’ll get from a wider tire run at lower pressure.

Rivendell has an excellent tire recommendation chart that breaks tire choice down by road surface and rider weight/load. View the chart here.

Which tire size do you prefer for utility riding?

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CenterTrack in the House

CenterTrack

For those who have been waiting and wondering (and sending emails), a care package arrived this week with everything I need to move forward with the Alfine 8/Gates CDX to Alfine 11/Gates CenterTrack upgrade on my commuter bike. The only thing I lack now is time. The work will happen this weekend, and if all goes well (knock on wood), I’ll have a report for you next week.


 
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