Soma San Marcos, an in depth review

This is my 51 CM Soma San Marcos purchased and built in Late September 2012. Built as an alrounder with a retro / randonneur vibe. For those who may not be familiar, the San Marcos was designed by Grant Peterson of Rivendell Bicycles for Soma Fabrications.
ALERT - this post is filled w/technical data that some may find boring. If you just want to know about the overall feel of the bike, just look at the pics and skip down to the final few paragraphs.



The Obligatory garage door photo

Even before my Cannondale was stolen from my garage I had already been searching for a new bike. I was looking into a semi custom Gunnar and playing with the geometry on bike CAD when I discovered the Soma San Marcos. I plugged the specs into Bike CAD and realized the San Marcos would give me the fit I was looking for at a much lower price, $800 vs $1650. Some may argue that there is a difference in quality between the two frames. The San Marcos is Tange Prestige with a Tange Infinity fork, while the Gunnar's are made from True Temper. I believe the main tube thickness for the San Marcos is a respectable 9/6/9. The feel of the Tange is compliant without being noodlish. I decided to pull the trigger and started collecting parts for the build.

Steve at Niantic Bay Bicycle built the 650b wheels at my request with Synergy machined side wall rims, Ultegra hubs, Wheelsmith double butted spokes and alloy nipples. At the time Velocity's 650b Synergy rims were the lightest ones available but the machined side walls were on back order for quite awhile. Eventually they came off back order and the build began.

The astute may notice dry cracks on the sidewalls.

I originally purchased a set of Dia Comp 610 center pull brakes, but the brake arms did not reach far enough on the rear. I lucked out because the shop had a rear Paul Racer hanging around. It had been too short on another build, so I got it at cost!  As you can see in the photo, the Paul Racers are just barely long enough.

Classic Rivendell Lugs

About 9 months after the initial build I up graded the front brake to a Paul Racer. I immediately felt a significant difference in the braking power.

Cane Creek 100 Classic threaded headset and a Funky Monkey

Even before I up graded the front brake, I changed the cable hanger to a Paul Components Funky Monkey. It kinda of sounds like a Ben and Jerry name doesn't it? Weird name, nice product.  

The Funky Monkey's barrel adjuster is by far the easiest to adjust of all the cable hanger barrel adjusters I have tried. The added length of the Funky Monkey reduces the amount of cable running from the barrel adjuster to the brake reducing the potential for cable shutter on a larger bike. 

Being able to adjust the Funky Monkey's barrel adjuster easily is vital since I've found it necessary to loosen it in order to open the brakes via the quick release when I want to remove the wheel.

Shimano 105 STI Brifters

Initially I had set up the bike with Shimano Tiagra brifters, since I had used them on the Cannondale and found them to be adequate. The new, at the time 4600 Tiagra line had just become 10 speed and had benefited from the higher end components trickle down affect.  The Tiagra's price point was a little easier to handle at the time of the initial build so that is what I put on the bike. The 4600 Tiagras had a different shape from the 4500 Tiagra I had on the Cannondale but I got used to it and found they shifted well with the 105 rear derailleur and IRD Alpina front derailleur. I later changed to the 105 brifters pictured above.

To me the 105 brifters have a nicer shape which is both more comfy and visually more appealing. The 105's also pull more brake cable thus increasing modulation. The cables exit at the handle bar making it easier to mount a small bag. One note about the 105 shifters, when shifting from the small 24 tooth chainring to the 36 tooth ring I have to give the shifter 1.5 shifts to get it to shift up to the 36 tooth ring. Interestingly with the Tiagra shifter the front derailleur was able to shift to the middle ring with only 1 shift. It was a little slow but it got there in one swing of the brifter's arm. Perhaps the extra turn the cable makes inside the brifter to allow it to exit at the handle bar creates just enough cable friction to cause this sub-optimal shifting with non Shimano parts. 

Note the flare of the 105 shifters

I had purchased a Nitto Randonneur handle bar for another bike, so when I was changing the shifters I decided to try them. Originally I had used the Nitto B115 drop bar, but I wanted a little more length in the ramps. I really love the shape of the Randonneur bar, the flare is very comfy and creates a sort of hip at the first bend. The increased length of the ramps allows me to move my hands more and gives my whole body a choice to be more upright or more aero.

Funny how one change leads to another.  After I changed the handle bar to give me what was essentially about 10 cms more reach I found I wanted my Brooks saddle setback more.  Sadly I removed the beautiful Thompsons zero setback seat post and replaced it with an old Sun Tour seat post w/setback which I found to be much more comfy. Eventually I changed to a Velo Orange Long Setback seat post which allows micro adjustments to the seat angle.



Velo Orange long setback seat post with Brooks saddle set all the way back.

Lovely Nitto Randonneur handle bar and a Nitto stem

The final change to the original build was the fancy gold Jagwire housing. I had to change the cables since I was changing shifters so I decided to go ahead and change the housing too.

Paul Components Light mount with Light & Motion Urban 550 light attached.

Here is the final Paul's product I have on the San Marco. It's their light mount which I have stuck a handle bar plug into and mounted it to half of an old brake arm, which I then mounted to the front rack. I used the brake arm to allow the light to be mounted a bit lower which makes it much easier to remove when needed. Otherwise it would be dead level with the rack, which sometimes causes interference with items on the rack. I like having the light mounted at tire height beneath the front rack.  You can see the road well without shining your light into the eyes of oncoming traffic and the cargo on the rack never interferes with the light's beam.

My front rack hack 

I only have one beef with Soma. Why didn't they have midfork braze-ons in the first place?  The new 2014 models all have midfork braze-ons, but the original models didn't.  So you have two options, use p-clamps to mount a front rack or get a different rack that allows you to mount to the dropout eyelets. The later is what I chose to do, although I think such an arrangement may increase the fork's stiffness.

  Originally I had a small cut down Wald basket mounted to the rack. This was quite convenient but baskets can also cause limitations in regard to the size of the load you can carry.  IE. I couldn't carry a 12 pack flat on its side. Thus my rack hack was born. It is the top part of the Wald basket bent to approximately a 10 x 10" square which I clamped onto the Velo Orange front Constructeur rack. 



Front rack in use, semi wet rain gear on the bottom with stuff from store on top all strapped down with a basket net.

The VO. Construteur front rack is quite strong and light at 425 grams. 

note the way the rack attaches to the fender in two places

I also installed a VO. Construteur rack on the rear of the bike. At 365 grams it is one of the lightest rear racks available. It is a bit small at 4.3 x 10.23 inches, the hooks of my inexpensive panniers just fit on the rails.  The rack is mounted to the fender and the rear dropout eyelets which is surprisingly sturdy.

 

Velo Orange Cranks and touring pedals

The crankset is a Velo Orange triple with 24, 36, and 48 tooth chainrings. I love my triple, combined with an Ultegra 12-30 cassette it gives me 21-105 gear inches. Now that's range!  I'm also quite fond of the VO. Touring pedals. They are super light at 236 grams for the pair while being plenty comfy and grippy. 

As I mentioned earlier I am using an IRD Alpina front derailleur. I chose the Alpina because it is supposed to provide better shifting with the smaller 48 tooth outer chainring. Perhaps if I ran a Shimano 105 front derailleur the shift from the small to the middle ring would be cleaner?  I wish Shimano would be like Sram in regards to having the same amount of cable pull for the road and mountain shifters.  This would allow both groups to be interchangeable and make it easier for someone like me who prefers to run smaller chainrings with STI shifters. 

All that being said, I don't spend a lot of time in the smallest chainring.  Most of the time I only have to shift from the 24 to the 36 tooth ring when I start out in the morning, since I park the bike for the night with it in the smallest chainring and sprocket.

 

The final bit of Velo Orange bling are the hammered fenders. Initially I had the VO. Zepplin 52 mm fenders for 650b wheels mounted but they were really wider than needed for 32 mm tires. Also it was my first time mounting a pair of aluminum fenders, hence errors were made. Here's a tip for anyone who has never installed metal fenders; squeezing the width of the fender to make it narrower effects the radius, essentially making it larger. I Eventually got the Zepplins installed but decided to change to the 45 mm hammered fenders later on.

I like the look of both fenders but the hammered fenders hide small scratches. I attached a Spanniga Pixeo Xba tail light to the rear fender, which required 2 holes to be drilled.

My first set of tires were Hutchinson 650b x 32 mm. I managed to get about 2300-2700 miles out of them before I had to replace the rear tire which was just about ready to go. Currently I am using the Grand Bois 650b x 32 mm Cypress tires. As you can see in the photo above, the sidewalls are getting cracked and dry. I also have a couple of small gashes in the tread of the rear tire, but I still have quite a bit of tread left. They have been run for approximately 2000 miles. 

 Soma San Marcos with the original build June 2013

So that's pretty much the build and some of my thoughts about it but what do I think about the finished product and the frame itself?  After riding 4500 miles I can say I am completely in love with this bike 95% of the time. The other 5% of the time I wished the bike were a bit lighter.

It's not really a heavy frame at about 6 lbs for the frame and fork, and I tried to select the lightest parts I could while still having all the features I wanted. Before I put the racks, kick stand and bag with gear on the bike it weighed 26 lbs.  Once I added the racks, etc. the bike gained 5 lbs. To loosely quote Grant Peterson,"it's hard to build a useful bike for less than 30 lbs".  The five percent of the time when I wish it were lighter I'm usually carrying some weight and/or going up hill or against the wind.

Lets get back to the 95% of the time when I am completely smitten with this bike. First thing is the fit, it's everything I hoped it would be. When I first started riding this bike It was like it was made for me. The Cannondale fit me pretty well once I had the stem extender installed, so that was my starting point when I started plugging dimensions into bike CAD. The San Marcos is 2 cm longer in the top tube, which I was a bit worried about, so I used a shorter 50 cm stem. Once I started riding the bike I was happy to have a little extra room to stretch out. 

 I am using a Nitto Technomic stem with about 4 inches of rise. Let me first say I love the threaded stem with it's ease of height adjustment. Also I personally prefer the aesthetic of a threaded stem. I must also compliment the geometry/design that Grant Peterson used on this bike. With a longish head tube set at  71 degrees, the higher you raise the stem the more it moves back towards you, effectively shortening the reach.

I also love the slacker seat tube angle of 71.5 degrees. That is an angle that is extremely hard to come by in a 51 cm frame, the typical angle is 74-75 degrees. My knees appreciate the slacker angle and I doubt that I would be able to use a leather saddle with their usually shorter seat rails if the seat tube angle was any steeper. 

 

 

Another uniquely Grant Peterson design is the lower bottom bracket height. With my seat set at maximum height for me I am still able to comfortably put my toe down while remaining seated at a stop light. The bike suffers no  clearance issues due to the lower bb. On the contrary I have ridden it through wooded trails filled with rocks and roots with nary a problem. 

The ride is sublime. It rides like a Cadillac, smooooooth.  I'm sure it must be the combination of the Tange Prestige steel and the supple 650b tires. On the road the ideal tire pressure for me is 60-55 psi in the rear and 40-35 psi in the front. Being a 51 cm bike I'm sure it is stouter than it needs be since a small diamond frame is inherently strong. On the other hand I have no worries that the tubes will dent easily and I have full confidence it can handle any load I pile onto it.

Aesthetically I never grow tired of looking at this bike. The color is a pearlescent turquoise which photographs more like a light blue. It is a difficult color to capture.  

Unless I one day have a custom frame built for myself, I am sure I will be riding the San Marcos for a long time.