The Fitting Process     I’ve spent most of the past three articles in this series talking about good bike fit and how it makes for a fast race.  The most expensive bike is not fast unless it’s the right size and has been fitted correctly.  An entry level bike can produce nearly as good a result as its five figure cousin in the hands of a creative bike fitter.  This issue I’m going to explain in some detail how I go about fitting a bike to its rider.  It’s not the definitive guide by any means (every bike fitter has ‘their’ method) but I thought it might fill in some of the detail around the emphasis on ‘correct’ bike fit.   So what are the mechanics of a good fit?  How does your fitter arrive at their conclusions?  I’ll talk you through a ‘typical’ day in the fit studio to hopefully shed some more light on this black art.     Step One – Coffee.   I don’t like to rush and I never start a fit unless I’ve had at least one decent coffee.  The first thing I need to know about the person I’m about to fit is what do they want the bike to do for them?  My shopping list of questions covers their race history thus far, their race calendar for the next year or so, injuries they’ve got, and why are they seeking out a bike fit.  I like to get an idea if they were a swimmer, biker or runner prior to joining the cult of tri, find out if they are working with a coach and what levels of training they are maintaining.  I also need to understand if I’m fitting them to a specific bike, or if they want me to help them select a bike that will best fit.  This sort of pre-fit conversation throws up all sorts of useful information and gives me a really good idea of what to focus on over the next few hours during the fit.  The fit will either be occurring because of the person being new to triathlon, buying a new bike (or wanting a new bike), the current bike being uncomfortable/injury issues or race results not being what they should be.     Step Two – The body and the bike   Human bodies are more alike than they are different.  It’s the commonality between people’s bodies that makes bike fitting formulas a good place to start.  On the other hand it’s the small differences between people that mean that the ‘numbers’ will only take us so far.  I start by running my fit subject through a few basic stretches to see what their flexibility limits are, get some idea of their inherent core strength and then attack them with the tape measure to see if they are more in the leg department or the arm/torso department of length.  A quick note on genetics…  Could you please ask your chosen deity or your genetics selectors (that would be your parents) to give you an even split between the two or if anything err a little on the torso side of the equation.  For the people who are all legs (and this includes the majority of girls) it makes the fit a tiny bit more difficult and your higher seat requirements mean a larger drop from saddle to aerobars and this can cause a few issues.  Fortunately most of the girls are reasonably flexible so this works out just fine.  For the guys with long legs, short torso/arm mesurements and limited flexibility, well you are my problem children.  Don’t worry a great fit is still possible but frame selection and component selection become more important at this point.  I take the view that most people can get a great fit on most tri frames as long as they have the right size frame.  Every so often I come across a person who is in the correct overall height for a given frame but their leg/arm/torso ratio makes getting a good fit near impossible (there is a limit to how many spacers your bike fitter can jam underneath your stem…).     Step Three – The Engine Room   I prefer to start at the back of the bike and work my way forward.  The first puzzle to solve here is the saddle.  For triathletes, who will spend large amounts of time seated on the bike and tapping out a steady rhythm on the pedals, then a comfortable saddle is the basic ‘Must Have’.  Comfort on a bike is a relative term but I’m trying to find a saddle that will not cause numbness or pain for the intended duration of the bike leg.  To date I have not come across a proven method for selecting saddles other than trial and error.  At the start of the fit I will rotate through a few different saddles until I find one that is comfortable and does not have the subject squirming around looking for their ‘happy place’.  The final selection of saddle will play out over the next few months (longer in some cases).  So it can take time to try different saddles to find the one that works for you.  Once I’ve got the person I’m fitting on a seat that is ‘OK’ then I can start the actual ‘bike fit’.   Next is pedal cleat placement and knee bend.  I’m a bit suspicious about bike fitters who can turn themselves into orthotics specialists overnight.  For serious foot issues I tend to refer out to experts in this field.  Fortunately most people don’t need expensive orthotics in their bike shoes.  For tri cleat placement I’m looking to get the foot well over the pedal spindle (mostly to support the rider who is more forward from a steeper seat tube angle) and I want their foot feeling nice and neutral in the shoe (no torsion through the ankle or knee).  A quick word on the plumb bob method…  I don’t think it works very well on tri bikes.  This method was developed around 72 degree road riding positions.  Moving to a 78 degree tri bike and the rotation of the pelvis and leg around the bottom bracket means the plumb will fall further forward along the foot, I’m not convinced this method is useful for tri fitting.   Once the saddle type, height and cleat placement are pretty close to being finalised we reach a critical point in the fit – seat tube angle.  Most good tri bikes allow for at least 76-78 degree adjustments.  This is an area where the fitting formulae are not of much use.  Some people ride better at steeper angles and some better at slacker angles.  This is very much a ‘what feels right’ moment rather than a prescriptive answer.  In some cases the person I’m fitting will automatically ride the same seat tube angle no matter where I put the seat, so this sorts itself out.  In other cases I have seen the people I’m fitting squirm in a steep position and then relax in a slacker position.  Sometimes finding the right seat tube angle can be a drawn out process involving multiple passes at different angles and sometimes it just clicks.  This is very much an area that is not suited to using a calculator to determine, it requires a good gut call and I’m always careful of keeping an open mind down the track that it may need to change as the athlete progresses.   Once the engine room is dialled in I move on to the hips through upper body.  To a certain extent my chosen seat tube angle will determine the hip angle.  The last part of the indoor portion of the bike fit revolves around moving the aerobar pads and extensions into a position to comfortably support the upper body.  I fit based on comfort first and then balance the power/aero component depending on how my fit subject is laying up on the bike.  My pet gripe is with the makers of aerobars.  Dear manufacturers, please note the following: triathletes are your biggest customer base.  They out buy time triallists by at least 10 to 1.  So, please understand that they have swimmer’s upper bodies and need to be on the bike for long periods of time.  Please make your arm rest pads adjust out wider, please make the arm rest pads bigger and please make better after market kits to allow for height and fore/aft adjustment independent of the extensions.  Please agree on a standard drill pattern for arm rest pads to allow your stressed and overworked bike fitter to put your beautiful and expensive aerobar in the right spot.   So the indoor ‘core’ adjustment part of the bike fit is nearly over.  To this point I’ve been guided by a set of angles and placements for feet, knee bend, hip angle, shoulder angle and elbow placement.  But, I’ve also remained willing to work outside these numbers to make the frame and the athlete live together happily.  I’ve tried to account for ‘invisible’ things like core strength (or lack of?) flexibility, weight and propensity to ride steep or slack.  Hopefully at this point the person being fitted is feeling better about life in general, wanting more coffee and a looking for a chance to get out of workshop and have a test ride in the real world.     Step Four – The Real World and other Iterations   If I’ve done my job, what feels good indoors will usually feel even better out on the road.  The remainder of the bike fit usually plays out over the next three months or so.  At this point I need real world data from the person I’ve fitted.  Their normal training rides and racing (leading up to their ‘big one’) give me all the info I need to continue to tweak the position until we get to a point where we mutually agree that no extra amount of bike fitting is going to result in a faster ride or run (and remember for most of us, a triathlon is a running race with wet hair, the bike is just the warm-up).  In some cases the fit is perfect straight off the bat, in more complicated cases I’m still making adjustments months after the initial fit.  It’s a case of comfort, results and temprement of the athlete that determine when my job is done.