Boardman AiR 9.8 in Fluid Platinum - collector's edition
Over the years, I have done fitting on myself and my friends. Armed with knowledge (read: mistakes) and observing pros and elites on how they setup their bicycle. Specialised bike fitting is expensive affair. It can cost anything from RM600 to well over a thousand ringgit. Some fitter allow for 2 bikes, typically a road bike and a triathlon or TT bike. For those asking, a TT and Triathlon bike is "same-same but different". A TT bike rides more aggressively with aerodynamic being the main purpose while a triathlon bike strikes a balance between comfort and aerodynamic. A Triathlon bike has a raised extension arm rest and a TT bike are often slammed all the way down unforgivingly.
Today, I will share what I know about fitting for a a basic road bike and TT fit you can do yourself. This is assuming you has procure a bike that fit your height.
Let's start with this sequence. The aim is a neutral position that is comfortable, stable and lets you produce power without rocking your hips or overreaching. Being comfortable meant you will be able to enjoy the experience better.
1. Set saddle height first
A practical starting point:
- Sit on the saddle with the bike supported.
- Put your heel on the pedal.
- At the bottom of the pedal stroke, your knee should be almost completely straight, without your hip dropping to reach the pedal.
- When you place the ball of your foot over the pedal axle, this should leave roughly 25–35° of knee flexion at the bottom of the stroke.
Signs saddle is too high: hips rocking, pointing your toes excessively, hamstring discomfort, feeling like you're reaching for the bottom of the stroke.
Too low: excessive knee bend, cramped feeling, burning quads, sometimes pain around the front of the knee.
Protip: Inseam method
If you want to get a bit more technical, you can measure your inseam (in cm) and multiply by 0.883 factor.
- Stand against a wall barefoot with your feet roughly 15cm apart.
- Use a book (hardcover) and press it against your groin. Book because it's 90 degree angle between you and the wall, versus using a ruler which may tilt.
- Measure the distance between the floor and the top of the book. Easier to get another person to help instead of doing it alone.
- Calculate inseam x 0.883. Measure from centre of bottom bracket to the top of the saddle, following the line of the seat tube.
- Adjust from here onwards, dropping or raising 5mm until you get a nice fit.
2. Saddle fore/aft
With the cranks roughly horizontal (3 o'clock position):
- Start with the front of the knee approximately around the pedal spindle.
- Treat this as a starting point, not an absolute fitting rule.
- Then assess whether the front of your knee is over the spindle (move seat behind) or behind the spindle (move seat to front). Aim for the knee right on the spindle.
For a triathlon bike, the saddle will normally be further forward than a conventional road position, expect a tighter fit between elbow-knuckle and consider fist to be on top of the steer tube/headset.
3. Saddle tilt
Most modern phone has a build in level gauge. Start essentially level (0°).
- Road: approximately 0 to -2° nose-down.
- Triathlon: often slightly more nose-down, particularly with split-nose saddles such as an ISM.
Avoid aggressively tilting the saddle down to solve discomfort. You may simply end up sliding forward and loading your arms.
4. Reach and handlebar height
On a road bike, when you're on the hoods:
- Elbows should have a slight bend.
- Shoulders should feel relaxed rather than shrugged.
- You shouldn't need to lock your elbows to reach the controls.
- You shouldn't feel as though you're constantly pushing yourself backwards with your hands.
If you're an endurance/triathlon rider, prioritize a position you can actually sustain for 2–5 hours, rather than chasing the lowest possible front end.
Protip: Sometimes the tilt of the brake hood plays a part in your overall comfort. Some bike come assembled in a way to get an aesthetically pleasing look (brake hood too flat for a clean streamlined handlebar look), so tilting the handlebar up 1 or 2° may help.
Lastly, if you are immediately planning to use a cleat (or clip).
5. Cleat position
Start conservatively:
- Place the pedal axle around the ball of the foot or slightly behind it.
- Set cleat rotation so your feet naturally point where they want rather than forcing them perfectly straight.
- Make sure left/right positions are reasonably symmetrical unless you have a reason for them not to be.
For long-distance triathlon, I generally prefer a slightly more rearward cleat position as the starting point rather than an aggressively forward one. Be warned though, that a slightly more rearward cleat position will take considerable effort to clip in due to the stiff sole that doesn't allow for flexion to clip more readily than the frontward position.
Protip: Setup a camera to record you from the back wheel, so you can see the movement of both left and right foot as you pedal down. Check to ensure your knee is tracking straight, and not flare-out. Adjust your cleat to enable a more neutral position of leg movement.
6. The ride test is important
After initial adjustment, ride 30–60 minutes and pay attention to where discomfort appears. These discomfort however may not manifest immediately in the first ride. Do bring a bike tool for minor adjustments as you ride. Even for experience fitters, they will offer a follow up readjustment based on your feedback. Do bear in mind that some of us do have imbalance torso (leg, hands, longer body, longer legs) that may throw some of the fitting off - especially when you attempt it yourself the first time.
| Symptom | First thing I'd investigate |
|---|---|
| Front of knee pain | Saddle potentially too low/forward |
| Back of knee pain | Saddle potentially too high |
| Hips rocking | Saddle potentially too high |
| Numb hands | Excessive reach/drop or too much forward weight |
| Neck/shoulder fatigue | Reach/drop |
| Saddle pressure | Saddle shape, position and tilt |
| One-sided knee pain | Cleat rotation/alignment or asymmetry |
| Sliding forward | Saddle tilt/reach/position |
| Can't comfortably stay aero | Aero reach, pad width/stack, saddle position |
Don't change several things simultaneously. Measure your starting position, change one variable, typically 2–5 mm at a time, and retest.
Do try the tips above - see you on the road!
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