Sue's Views: on the ragged edge at La Ruta

Trek-VW SUPERSTAR Susan Haywood just wrapped up the overall victory at La Ruta in Costa Rica.  She's got a crazy story to tell!!  Check out the race website as well as Sue's blog.

I sat on the starting line  on stage one of the La
Ruta de los Conquistadors mountainbike stage race.  I
was nervous as hell.  It was dark, about 5:30 in the
morning.  The fireworks celebrating the 15th year of
the race were really spectacular, but they hardly put
me at ease.  I worried about my fitness, did I train
enough?  I was worried about the chaotic nature of
racing south of the border.  Would I collide with a
moto or get bit by a dog?  I was nervous about hurting
myself.Would I break my upper mandible like Jeremiah
did here last year?

But one of the biggest worries of the morning was the
bike.  My sweet carbon 9.9 was MIA.  My suitcase
showed up at the San Jose Airport, but the bike never
made it.  The TACA airlines clerk said don't
worry...think positive!  That actually made me feel
better and I was sure it would show up later that
night or the next day or at least before the racce.

I called Luis Fonseca, the marketing director, who
invited me down to La Ruta after we met at Trans
Rockies.  The tone of his voice said it all, "oh know,
that's not good"  He wasn't saying no problem like the
clerk.  He mobilized and said I'll call the local Trek
dealer and get you a bike for the race. 

Its good to have a Trek family all over the world! In
the morning I was taken over to Pazos bike shop owned
by Claudio Brenes.  I guess they helped Jeremiah last
year when he was hurt.  They didn't have a bike right
there for me, but they would bring it to Jaco Beach
that night.  They got my info like size, stem size,
tires and pedals.  Super, I was set.

So, at least I was going to be able to race.  The guys
from the bike shop drove all the way to Jaco Beach to
deliver me a bike.  They arrived at 11.  The race
started in six hours.  The bike was a beauty, but lost
in translation was my size.  It was a small 9.9.  It
seemed like a toy bike as I pedaled it around in the
hotel lobby.  We were both a little disappointed.  I
said to myself you have to learn spanish so these
awkward moments don't happen so often. 

So as I sat on the start line with 550 other racers, I
felt the nerves of the unknown.  What will this day
bring?  Will my back seize up?  Will the front wheel
come flying out?  Are all the bolts tight?  What does
15,000ft of climbing feel like?

The day was amazing and difficult.  The bike was
great.  It was a little small, mostly because of the
short stem.  It was quite good on the climbs, but on
the downhills I was wanting my bike for sure.  I
stopped once to raise the saddle, but thats it.
Whenever I was hurting I wondered if it was the bike ,
or just my november fitness.  But, by the end of the
day I was in the leaders jersey of La Ruta!  It was a
long day on someone else's saddle, but It was success.

I continued to call the airlines with no progress. I
won day two on the borrowed bike.  I was getting used
to it.  I always wanted a bike with a shorter top tube
so that was pretty cool.  What wasn't so cool, was the
absurd amount of climbing on day two.  Day one was
15,000ft of uphill and day two was 12,000.  Someone
said that there were grades of up to 38% on pavement
that day.  The hardest part was never knowing where
the summit was.  The most soul crushing part was after
all that climbing, the downhill singletrack was a
slippery clay ditch that was hazardous to even walk.
There was a cliff to one side that some racers even
slipped off of.  I was cussing the promoter, Roman,
for sure.  But I couldn't be too mad having won the
stage and grown my race lead.

TACA was really starting to piss me off as well.  They
were starting to act like it was my fault that my bike
wasn't with me.  I implored the help of Hillary
Harrison's mom, Karen, and her friend, Pipa.  Karen
said if anyone can get your bike back its Pipa.  Pipa
called and explained who I was, how expensive my bike
is and how important it is that I get that bike back
to continue as the leader of La Ruta.  Pipa convinced
them and I got my bike later that night.  Apparently,
it had gone to Panama for several days.

So, day three I got to ride up the Irazu Volcano on my
own bike.  I was putting a little pressure on myself
now.  Would I be tons faster on my own bike.  Well the
funny thing was, I couldn't get too comfortable on my
own saddle.  Maybe the damage was already done.  I
struggled up the volcano.  It was only 9,000ft of
climbing today.  But, on the downhill I was so happy.
Finally, La Ruta has a downhill.  And I felt great on
my bike on the downhills.  It was a burly downhill and
claimed a lot of victims, including JB last year.

Day four was brtually long.  It was 120 Km and a lot
of pedaling over very rough roads and railroad tracks.
I was not very motivated to push it.  I was in stage
race mode...protect the lead and thats it.  Do the
minimum to win the overall.  Thank god, I had Louise
to follow the whole day.  I trusted her lines and her
experience on this last day.  It was over 6 hours of
riding for a total of 23 hours in four days!

La Ruta was crazy hard, but such a thrilling and
challenging experience that I would recommend that
everyone give it a try.  It is exactly the hurt so
good experience that mountainbike racers love!

It did take its toll on my body, though.  I got a
quick stomach bug for about three days after I came
home and then I got a bad cold after that.  Plus, my
bike is trashed.  The hubs won't spin at all.  The
white lithium grease is still packed in every part of
the drive train and the kerosene is eating away at
every surface it can.

But, La Ruta was an experience of a lifetime!

Conquering La Ruta de los Conquistadores

Trek-VW's Susan Haywood and top Texas regional rider Scott Henry ventured to Costa Rica for La Ruta de los Conquistadores last weekend.  Scott's report is below:

La Ruta de los Conquistadores 2007

This year the organizers shook things up a bit.  Rather than the 3-day grueling race of the past 14 years, it was now a 4-day stage race in celebration of its 15^th anniversary.  The extra day allowed the journey to be a true coast to coast adventure across 9 microclimates, spanning from Playa Jaco in Jaco and ending at Playa Bonita in Limon.

Approximately 550 riders began at the start line at 5am on Day 1, a number which significantly decreased over the next 3 days.  Susan Haywood and I representing Trek were at the start, along with Tinker Juarez, Frederico Lico Ramirez, Thomas Dietsch and several other top endurance racers.

Each morning began with a wake-up call between 3 and 4am, breakfast at 4:15, all personal items packed and loaded on buses by 5 and the race kick-off at 6:30.  Between the time we arrived and the start of the stage, there were about 30 minutes to find our bikes in storage and make sure they were in the same condition we left them the night before.  Lucky for me my Trek Fuel stayed in excellent shape so I wasn’t at a disadvantage of having to make last minute repairs before the start.

Stages lasted anywhere from 3 ½ hours to as many as 12 hours, depending on the rider.  Following each stage riders would shower, go through the buffet line, then wait for the buses to shuttle them to the new hotel of the night, sometimes as much as an hour and a half away and 8,000 feet higher than the stage finish, only to re-fuel, re-pack and return a few hours later for another exhausting day on the bike. 

Broken collarbones, dislocated shoulders, intestinal disorders, broken ribs, and as many as 100 stitches in a single arm were among a few of the injuries and illnesses encountered in the almost 8 miles of vertical climbing and descents through mud, rivers, rock, cow manure, broken railroad trellises and other grueling terrain. 

The race was truly an adventure mentally, physically and logistically, but one I would recommend for any passionate and talented rider. 

Susan Haywood of Trek finished 1^st in the Women’s Division and I finished 5^th in the Masters A division.

Check out www.adventurerace.com for more course & race information.

Tech Talk with Dylan: In Response to the Comments

Recently, a few comments have emerged on this blog in regards to Trek’s Full Suspension Technology.

At first, I was a little thrown off by how each poster wasn’t posting in exactly the most friendly manner, but then I remembered that forums and blog postings can be rude. And, when dealing with a large company, it’s easy to forget that there are actual people dealing with things.

So, rather than lash out at each poster and degrade them for poor etiquette, inexperience and just plain rude attitude, I decided to ask Dylan and Jose, our in-house suspension gurus.

Hold tight, this is going to be a long post.

But before you get started, here are a couple book suggestions courtesy of Jose Gonzalez that will help you understand the issues:

Motorcycle Tuning : Chassis by John Robinson (partial ibook download)
Motorcycle Design & Technology by Gaetano Cocco (for purchase at motorbooks.com)

And now, here’s a look at the comments that inspired the feedack.

Comment:
“I just read the article. I can't say I am buying the "engineering" behind the hype. First off, the  graph which shows the comparison between 07 and 08, where the first bullet states better small bump compliance while the graph shows lower initial leverage ratio is a clear mistake. Lower leverage ration means the suspension is harder to compress, so no, it is not more supple for small bumps. Your comments on DW-Link are also incorrect. Since the air spring has a progressive rate curve with very little progression in the mid stroke (curve nearly flat), it is wise to reduce compression ratio, which reduces the wallow, whereas at the end of stroke, it is again wise to increase the leverage ratio to fight the highly progressive behavior of the air spring and be able to achieve full travel. These are just a couple of comments I have. Seems like the Full Floater would be best used with a coil sprung shock. A high volume sleeve air shock may work OK as well.
- Michael K”

Comment:
“The Trek spiel is incomplete and has some really bad mistakes as well. Spring curve changes with starting pressure?! Wrong. The shape of the curve is the same starting with 10 psi or 10000. Not debatable, just wrong. They don't include the shock spring curve and the force at the rear wheel vs travel. You'd see a graph of what the rider feels. It's a level or two deeper in the calculations. Maybe next year. Then the following year, they can start on anti squat. After that they can ask Dave for a license once they understand what's going on!
-Rick”

We would like to start by apologizing to both of you. I can understand your need to argue over this as we’ve obviously made you feel very bad about your own bikes, thus ruining all your rides since reading this.

Rick, you’re absolutely right – shape of the curve doesn’t change with pressure change. However, the higher pressure creates more stiction, and combined with the higher compression damping needed, the rider will feel a firmer overall ride.

Michael K, you’re also right. A lower lever ratio does mean the suspension is hard to compress – at the same pressure or spring rate. But for the same travel and rider weight, a lower initial ratio means less air spring pressure is needed, reducing friction, and allowing a more fluid suspension response.

You’re right too that we didn’t include the “force at the rear wheel vs travel” graph. However, the information from that chart only shows the amount of force required to move the wheel at any given point in the travel. It does not show the effect of the damper and the speed at which the shock shaft is moving -- and that is a more accurate picture of what the rider feels than just spring force. That's the reason that we look at and manipulate instant leverage ratio curves to truly “tune” how the system feels to the rider.

“A level or two deeper in the calculations”? Hardly!

“Force at the wheel vs travel” is one of the first things I look at as a frame designer – it’s what is used to determine loads on the system, and what I use to determine bearing sizes, pivot sizes, tubing wall thicknesses, etc. The “level or two deeper” part is understanding that instantaneous lever ratios are the true variables that affect suspension feel and response.

Michael K, again you’re completely right in referring to how leverage ratios should work with an air spring. Reducing leverage ratio works extremely well in helping to control the flat mid-stroke curve of an air spring, and increasing it at the end allows the system to reach full travel with the progression of an air spring.

However, here is where actual suspension design experience comes in handy. SOME leverage ratio increase at the end helps the system get full travel – the Mojo’s huge regression at the end leads to blowing through the travel at the end if the shock is properly set for sag and small bump compliance. If the shock were set to deal with this huge regression, the overly high levels of compression damping needed would make the bike feel harsh initially and on small bumps. As we stated, it is nearly impossible to tune a shock to work properly with such levels of ratio change.

And then of course there’s “anti squat” -- what the motorcycle guys have understood for years and refer to as “Chain Pull Effect.” Chain pull effect refers to the drive system’s (in our case, the chain and drivetrain) ability to extend the rear suspension. This is generally a good thing – when we accelerate, the weight shift causes the suspension to compress, and extending the suspension helps work against this. Extending the suspension also helps push the tire into the ground, increasing traction (especially helpful in steep climbing situations, for example). The higher the chain pull, the more suspension will want to extend. So more must be better, right?

Now keep in mind that although this sounds good on paper, our “motor” has a pretty low frequency to it, has a very on-off power stroke, and has two heavy, oscillating pistons that move through a large stroke.
When you combine this highly on-off power system with a bicycle that “rides” at sag – that is, about 30% on average into the suspension travel, and given that “chain pull” forces want to pull the suspension all the way to fully extended (there is no magic to make it stop pulling at sag) and you can easily see how too much “chain pull” quickly leads to a very “bobby” ride. Power on, pull chain, extend suspension, power off, suspension sinks back to sag. Power on, pull chain, extend suspension…..

The calculations and diagrams used for determining chain pull have been used by motorcycle designers for years and are exactly the same as used to determine chain pull effect in bicycles. So let’s take a look at how some various designs stack up. Keep in mind, this is shown in the same gear for all bikes. These curves move depending on the gear – no way around that, no magic that changes that.

The Santa Cruz Blur LT actually has more chain pull the deeper you get into the travel. This does actually make the Blur a very efficient pedaler. However, this comes at the expense of large amounts of pedal feedback, and a system that has to have very high bump force to overcome the chain induced suspension extension. In other words, suspension extension is always fighting against bump absorption, meaning efficient pedaling, but less effective suspension.

Due to its low instant center, the Specialized FSR bike has a very low amount of suspension extension under pedaling. While this does make for good bump absorption and a very active suspension, there is not much force to resist suspension compression due to weight shift. This is why FSR bikes are not very efficient pedalers and are reliant on high levels of shock platform or lockouts.

The Iron Horse MkIII, while an efficient pedaler, has higher levels of suspension extension early on in the travel, and like the Blur, this translates to loss of small bump compliance because of the higher mechanical extensive force the system has.

The Ibis Mojo actually has less suspension extension than the Trek Fuel EX at sag. And although it has higher levels deep into the travel, that is worthless as the rider is never going to really be pedaling that deep into the travel. Since full suspension bikes are designed to ride at the sag point, having high levels of chain pull very early in the travel actually works against small bump compliance. That is, by engineering a bike with more chain pull effect early in the travel, the bike is suspension is actually less efficient for pedaling, even working against you rather than for you.

The pivot location of the Trek Fuel EX has been carefully chosen and tweaked over the years to give us exactly the pedaling efficiency we’re looking for – this is not something we simply picked. It has been chosen and modified to give us exactly the balance of pedaling efficiency, minimal pedal feedback, and ability for bump force to overcome pedaling extension force that we were looking for and have honed over many years.

Keep in mind too that these chain pull forces are pretty small and the differences are not huge. You can see from the graph that at sag, all these bikes have similar amounts of chain pull. Although someone might make an argument as to why a higher chain pull force might be desirable, there is no denying that this comes at the expense of lower small bump compliance, more pedal feed back, and a linkage that combines more bearings, parts and complexity in an area subject to very high loads, limited clearances and close proximity to mud and dirt.

Also, simply designing around a particular suspension extension amount means nothing without designing the bike to work as a whole. The bike’s geometry, stiffness, weight, instantaneous lever ratio, chain pull effect, and shock tuning all have to be considered and designed for AS A WHOLE. All those factors work together to give the bike the ride it has.

I hope this helped give a clearer picture of why we've done what we've done.

I am ICEMAN!

Rad Ross Schnell is back in the competition mode!   He journeyed to Michigan for the Iceman Cometh race, and here's his story:

This past weekend I found myself traveling to Michigan for a dose of Midwest racing at its finest--the Iceman Cometh. I'm pretty sure the odds were stacked against me going in, which made for a rather entertaining weekend. My first mistake was having a flight connection through Chicago O'hare Airport, the bermuda triangle of airline travel and bike transport. I was convinced that they would either a) lose my luggage and/or bike, or b) delay my flight and arrival time at a reasonable hour. Turns out, they only damaged the bike and delayed my flight. I arrived about midnight in Traverse City and was absolutely stoked and rather surprised to see that my luggage had arrived. My pre-race dinner consisted of several delicious Cinnabon cinnamon rolls at the airport, and topped off with some late night carbo-loading at the local drive-thru Wendy's. Race day dawned with blue skies and a balmy 44 degrees for a high. Luckily for me, the weather was condusive to wear the full length, one-piece, aerodynamic Trek "rocket-boy" skinsuit from 1989. Got to the  start about an hour before go-time and began building up the bike. Shortly after starting my solid 15 minute warmup  I realized that the derailleur hanger (and der cage) were totally mangled from the flight. Upon seeing this, I set about attempting the roadside repair
approach of eyeballing the thing till it kinda-sorta-maybe looked straight. With race time approaching, I rode through the parking lot and arrived at the start line with a couple minutes to spare. With 3 minutes until the gun went off, I looked down and noticed a soft and nearly flat front tire. I frantically ran through the parking lot to find a front wheel and handed mine off to some random dude. Found the wheel after the race and heard the story of my front wheel flying off the roof of his car going down the freeway on the way to the finish. The whole weekend was a comedy of errors! The race went ok, except that mid-west racing is really hard and I guess I'm not in very good shape when it comes to riding 30mph on flat roads with sandpits and no technical riding. I got spit out the front group about 40 minutes in and proceeded to stop on the side of the trail more than a couple times to jank with the roached drivetrain and pull the chain out of the spokes. You start to lose motivation after a couple of forced pitstops, but nonetheless I finished and had a good time doing it. The crowds up there were ridiculous, you can't help but be energized by the throngs of crazy fans cheering you on. There were so many cowbells and screaming people that it seriously hurt my ears to ride through it! Good times followed up with a kickin' party on saturday night. I look forward to giving the mid-west bike racing thing a try
in the future!

World Bicycle Relief