Here's the thing nobody tells you about bike fitting: it doesn't end when you walk out of the studio.
You've spent $300 on a professional fit. The fitter has dialled in your saddle height, your reach, your cleat position. You've got a fit sheet with numbers measured to the millimetre. You ride home and everything feels brilliant. Three months later, your lower back starts aching. Six months later, your hands go numb on anything over two hours. A year later, you're back where you started — uncomfortable, confused, and wondering if that expensive fit was a waste of money.
It wasn't. But it was a snapshot. A photograph of your body on that day, in that state of flexibility, at that weight, with that level of fatigue. And your body didn't stay in that state. It never does.
Here's where it gets really interesting: the riders who stay comfortable year after year aren't the ones who got the best initial fit. They're the ones who treat their fit as a living, evolving thing — something that needs attention every few months, not every few years.
Let me break this down.
Why a Single Fit Is Never "Done"
The entire premise of a one-and-done bike fit is built on a flawed assumption — that your body is static. It isn't. Not even close.
Between the day you get fitted and six months later, at least three things will have changed. Your hamstring flexibility has shifted, either because you've been stretching consistently or because winter took you off the bike for eight weeks and everything tightened up. Your core strength has changed with your training load. And if you're over 40, your thoracic spine mobility has continued its slow, relentless decline.
Phil Burt has talked about this on the podcast, and it's one of the most important things I've learned about fitting. He doesn't see a bike fit as a single intervention. He sees it as the first step in an ongoing conversation between you, your body, and your bike. When he fitted riders at Team Sky, those athletes weren't getting one fit per season. They were being assessed continuously — after crashes, after training blocks, after illness, after off-season weight changes. The fit evolved because the rider evolved.
Now, you're not a WorldTour pro. You don't have a fitter following you around. But the principle still applies. Your body is changing month to month, and your position needs to change with it.
Three factors drive this more than anything else.
Flexibility changes. This is the big one. Your hamstring range, hip flexor length, and thoracic rotation don't stay constant. They respond to training, to stretching, to sitting at a desk for ten hours a day, to that period where you didn't ride for six weeks because life got in the way. A fit that was set for your January flexibility won't be right for your July flexibility — or vice versa.
Strength changes. As your core gets stronger through consistent riding, you can sustain a more forward position without loading your hands and wrists. As it weakens during the off-season, you can't. This is why many riders find their hands going numb in January and February — their core has lost the fitness to support the reach they were comfortable with in August.
Age. I know nobody wants to hear this, but it matters. After 40, hip flexor range decreases by roughly 3-5 degrees per decade. Thoracic mobility declines. Shoulder flexibility changes. These aren't dramatic shifts year to year, but over five years, they accumulate enough to turn a comfortable position into an uncomfortable one. If you got fitted at 42 and you're now 47, your body has moved on even if your bike hasn't.
The 3-6 Month Review Cycle
The question most riders ask is: how often should I actually look at my fit? And the answer is simpler than you might expect.
Every three to six months, do a structured self-assessment. Not a full re-fit — that's overkill unless something is specifically wrong. A self-assessment is a 20-minute check that tells you whether your current position is still working or whether something has drifted.
Here's the protocol I use, and it's based on what I've picked up from fitters like Phil Burt and Steve Hogg over years of conversations.
The Quarterly Self-Assessment
Step one: the pain audit. Before you change anything, write down any discomfort you've experienced in the last month. Be specific about location (inside of left knee, base of right thumb, right side of lower back), timing (after 60 minutes, only on climbs, only at high cadence), and severity (mild annoyance vs. ride-ending). This matters because pain is information. It tells you where the fit has drifted.
Step two: the visual check. Set your phone up on a tripod or ask a mate to film you from behind while you ride on the turbo for five minutes at a moderate effort. You're looking for three things: does your pelvis rock side to side, do your knees track straight over the pedal spindle or do they drift inward or outward, and does one hip drop more than the other. You can't feel these things while you're riding. You need to see them.
Step three: the flexibility snapshot. Three tests, done cold — not after a ride, not after stretching. First, sit on the floor with straight legs and reach for your toes. Measure how far past your toes you can get (or how far short). Second, lie on your back and pull one knee to your chest while keeping the other leg flat — check whether the flat leg lifts off the ground (tight hip flexors). Third, sit upright on the floor and rotate your torso as far as you can in each direction — note the range. These three measurements, tracked every three months, tell you whether your flexibility is improving, declining, or staying the same. And that tells you whether your position needs to move with it.
Step four: the ride test. Go for a ride of at least 90 minutes at your normal intensity. Don't think about your position — just ride. After the ride, note any new discomfort or any old discomfort that's returned. Compare it to your pain audit from step one. If nothing has changed, your fit is probably still good. If something new has appeared, it's time to investigate.
When to Book a Professional Re-Fit
The self-assessment tells you whether something is off. It doesn't always tell you what to do about it. Here are the triggers for booking a professional session:
- Your pain audit shows a problem that has persisted for more than three weeks despite self-adjustment
- Your visual check reveals asymmetry you can't explain (one-sided hip drop, significant knee tracking issues)
- Your flexibility snapshot shows a decline of more than 2-3cm in reach or noticeable hip flexor tightening
- You've lost or gained more than 4-5kg since your last fit
- You've had an injury that affected how you move — even something that seems unrelated to cycling, like a twisted ankle or a shoulder issue
For most riders doing the self-assessment honestly, this means a professional re-fit once a year. For masters riders over 50, twice a year is worth considering.
What You Can Safely Adjust Yourself
Not every fit change requires a studio appointment. Some adjustments are safe, simple, and actually better done by you over time because you can feel the results ride by ride.
Here's the list of what's in your territory.
Saddle Fore/Aft: 2-3mm at a Time
This is the single most forgiving adjustment on the bike. Moving your saddle forward or back by 2-3mm changes where your weight sits relative to the bottom bracket, and you'll feel the difference within a ride or two.
Forward = more weight on your hands, more quad engagement at the top of the pedal stroke. Back = less pressure on hands, more hamstring and glute loading.
The rule: move it 2-3mm, ride for a week, assess. If the change improved things, leave it. If it made things worse, move it back. If you're not sure, ride another week. Never move it more than 3mm at a time — larger jumps make it impossible to isolate the effect.
Bar Angle and Hood Position
If your wrists ache in the hoods, your hoods might be rotated too far up or too far down. If your hands go numb on the drops, your bar angle might be pushing too much weight forward. These are Allen-key adjustments that you can tweak in minutes.
The test: sit in your normal riding position on the hoods. Your wrists should be in a neutral position — not bent up, not bent down. If they're cocked at an angle, rotate the hoods until they're neutral. It's that simple.
Saddle Tilt
Small changes in saddle tilt — we're talking half a degree to one degree — can make a significant difference to perineal pressure, lower back comfort, and how much weight transfers to your hands. Most riders do well with a level saddle or one tilted very slightly nose-down (1-2 degrees maximum).
Use a spirit level app on your phone to measure it. Adjust in half-degree increments. If you tilt the nose down too far, you'll slide forward and load your hands more. If you tilt it up, you'll increase soft tissue pressure. The range of acceptable tilt is narrow — stay within 2 degrees of level in either direction.
Spacer Changes (Small Ones)
Adding or removing a single 5mm spacer under your stem is a safe self-adjustment. This changes your bar height and therefore how much your torso tilts forward. If your neck and upper back are aching on long rides, a 5mm spacer added under the stem can take enough load off that area to resolve it.
One spacer at a time. Ride for two weeks before deciding. And know that adding spacers raises the bar but also slightly shortens the reach — you might need to nudge the saddle back 1-2mm to compensate.
What Needs a Fitter
Here's where I need to be really clear: some adjustments create ripple effects through your entire position, and getting them wrong costs you more than getting them right saves you. Leave these to a qualified fitter.
Cleat Position
Cleat fore/aft and rotation affect your knee tracking, your ankle stability, and the load distribution across your foot. Phil Burt is emphatic about this one — cleat position is not a guess-and-check exercise for most riders, because the effects are delayed. You might feel fine for three weeks and then develop a knee issue that traces back to 2mm of cleat rotation. A fitter watches your knee tracking in real time and sets the cleat to match how your body actually moves, not how you think it moves.
The exception is if your cleats have float (most SPD-SL and Look cleats do). Float gives you a range of rotational freedom at the cleat, so small errors are partially absorbed. But fore/aft cleat position — how far forward or back the cleat sits on the shoe — has no float to cushion mistakes.
Stack and Reach Changes
Moving the stem length, flipping the stem, or making significant spacer changes (more than 5mm) alters the fundamental relationship between your saddle position and your handlebars. These changes need to account for your spinal flexibility, shoulder width, arm length, and core strength simultaneously. A 10mm longer stem doesn't just make you reach further — it changes your weight distribution, your elbow angle, your shoulder loading, and how much your lower back has to stabilise.
This is interconnected stuff. It's not one variable — it's five variables that all shift together. A fitter sees the whole picture. You see the one thing you changed.
Crank Length
I've written about Phil Burt's approach to crank length before, and his position is clear: crank length comes first in a fit because everything else is built around it. Changing crank length changes your saddle height, your knee angle at the top and bottom of the stroke, your hip closure, and your ankle mechanics. If you change it without adjusting everything downstream, you'll create problems in places you didn't expect.
This is categorically not a home adjustment. If you suspect your cranks are too long — and for most masters riders, they probably are — that's a conversation for a fitter who can set the new length and rebuild the rest of your position around it.
The Four Red Flags Your Fit Has Drifted
Your body is good at compensating. It will adapt to a sub-optimal position for weeks or months before the discomfort becomes obvious. But there are four warning signs that are reliable indicators your fit needs attention. Learn to recognise them early, because catching a fit issue at week two is a 20-minute self-adjustment. Catching it at month six is a $300 re-fit and three weeks of recovery.
Persistent Knee Pain
Knee pain is the most common and the most specific fit indicator. Where the pain sits tells you what's wrong.
Inside of the knee (medial): Almost always a cleat issue. The cleat is rotated too far outward, forcing the knee to track inward during the pedal stroke. Or the saddle is too high, causing the knee to overextend at the bottom.
Outside of the knee (lateral): Often the opposite cleat problem — too much inward rotation — or an IT band issue aggravated by a saddle that's too high.
Front of the knee (patellar): Saddle too low or too far forward, causing excessive load on the quadriceps tendon at the top of the stroke.
Behind the knee: Saddle too high, causing the hamstrings to overstretch at the bottom of the stroke.
The pattern here is useful: knee pain almost always traces back to saddle height, saddle position, or cleat setup. It's rarely random, and it's almost always fixable.
Numb Hands
If your hands go numb or tingle after 60-90 minutes, too much weight is on your handlebars. This is usually one of three things: the reach is too long, the bar drop is too much, or your core isn't strong enough to support your current position.
The first two are fit issues. The third is a fitness issue. How to tell the difference: if your hands go numb at the start of the season but not in August, it's probably core strength — your off-season fitness has declined and your body is dumping weight onto your hands because your core can't hold it. If your hands go numb consistently regardless of fitness, it's the fit.
Short-term fix while you investigate: move your hand position frequently — hoods, tops, drops, rotate through them. And check that your hoods aren't rotated too high, which forces a wrist angle that compresses the ulnar nerve.
Lower Back Tightness
This is the one that creeps up on you. Lower back tightness that builds through a ride — especially on efforts over 90 minutes — usually means one of two things. Either your reach is too long, forcing your lower back to stabilise a position your core can't support. Or your saddle is too high, causing your pelvis to rock side to side with each pedal stroke. That rocking creates a repetitive micro-strain on the lumbar spine that compounds with every revolution.
Phil Burt's first move here, as I've written about before, is to check crank length. If the cranks are too long for your hip flexibility, they force excessive hip closure at the top of the stroke, and the body compensates by rounding the lower back. Shorter cranks open the hip angle and take the load off the spine. It sounds counterintuitive, but it's one of the most reliable fixes he uses.
Neck Pain and Headaches
Neck pain on the bike is almost always an extension problem. You're reaching too far forward, which means you have to crane your neck more to see the road. Or your bars are too low, which increases the angle your neck has to extend through.
This is one that gets worse with age because cervical spine mobility decreases. A position that let you comfortably see the road at 35 might have you straining at 50, even if nothing on the bike has changed.
The fix is usually a combination of a shorter stem or higher bars and off-bike neck mobility work. But the key point is that this is a fit issue presenting as a pain issue. No amount of stretching will fix a position that demands more cervical extension than your spine can deliver.
How Weight Changes Affect Your Position
This is the one most people don't think about, but it's significant. If you've lost or gained more than 4-5kg since your last fit, your position has shifted even if you haven't touched a single bolt on the bike.
Weight Loss
When you lose weight, three things happen to your position. First, your saddle pressure distribution changes. Less tissue between your sit bones and the saddle means the contact pattern shifts, and a saddle that was comfortable at 85kg might not be at 78kg. Second, your flexibility usually improves — particularly in the hamstrings and hip flexors — because there's less tissue restricting the range of motion. This means you can potentially sustain a slightly more aggressive position. Third, your centre of gravity shifts, which changes the weight distribution between saddle and handlebars.
The practical implication: after significant weight loss, you might benefit from a slightly lower saddle position (your effective leg length changes when tissue volume changes), a slightly more forward and lower bar position (because your flexibility allows it), and possibly a different saddle entirely.
Weight Gain
The reverse applies. Weight gain typically reduces flexibility, increases soft tissue pressure on the saddle, and shifts your centre of gravity. The body's natural response is to sit more upright to take pressure off the hands, but this loads the lower back more.
If you've gained weight and your lower back is bothering you, the instinct is often to raise the bars — and that might help. But check the saddle situation first. More weight on a saddle that no longer distributes pressure well will cause you to shift your pelvis, and that pelvic shift is what creates the back pain. Sometimes the fix is a saddle with a wider profile or a different cutout, not a higher bar.
Keeping a Fit Log
Here's a small piece of practical advice that pays off massively over time. Keep a fit log.
It doesn't need to be complicated. A notes app on your phone is fine. Record these measurements every time you change something:
- Saddle height (centre of BB to top of saddle)
- Saddle setback (from the nose of the saddle to the centre of the BB, measured horizontally)
- Saddle tilt (degrees from level)
- Bar reach (from the saddle nose to the centre of the bars)
- Bar drop (from the top of the saddle to the top of the bars)
- Cleat position (take a photo of each cleat from above — it's the easiest way to record and reproduce it)
- Date and reason for any change
This log does two things. First, if something goes wrong, you can reverse your last change precisely. Second, when you visit a fitter, you can hand them a history of what you've tried and what happened. That context is worth 20 minutes of their assessment time. They're not starting from scratch — they're building on data.
Over a few years, patterns emerge. You might notice that every January you nudge your saddle forward 2mm because your hamstrings tighten over the off-season, and every June you move it back. That's useful information. It tells you something about your body's seasonal flexibility pattern, and it turns an unconscious adjustment into a conscious one.
The Annual Cycle in Practice
Let me put all of this together into what an annual fit maintenance cycle actually looks like for a masters rider.
January (start of the base season). Do a full self-assessment. Check flexibility, film yourself on the turbo, note any discomfort from the off-season. If your flexibility has declined, consider adding a 5mm spacer and moving the saddle back 2mm. Ride for two weeks and reassess.
April (as volume and intensity increase). Second self-assessment. Your fitness is building, your core is stronger, your flexibility is returning. You might be able to remove that winter spacer. Check that your knee tracking is clean now that you're putting more power through the pedals.
July (peak season). You're at your fittest and most flexible. This is often when riders feel best on the bike — and ironically, it's the best time for a professional fit, because the fitter is seeing you at your functional best. The position set now represents what your body can sustain when everything is working well.
October (end of season). Quick self-assessment before the off-season. Note your current measurements so you have a benchmark to return to. If you're planning to ride through the winter, no changes needed. If you're taking time off, accept that January will require a reassessment.
This cycle isn't rigid. Life intervenes — injuries, illness, travel, motivation dips. But the framework gives you a structure that catches fit drift before it becomes a problem.
The Off-Bike Work That Makes Your Fit Last
A fit is only as stable as the body it's built on. If your flexibility and core strength fluctuate wildly through the year, your position needs to move with them — and you'll spend more time adjusting than riding.
The riders who maintain a stable position are the ones who do consistent off-bike work. Not hours of it. Three sessions a week, 15-20 minutes each.
Flexibility work. Hamstring stretching, hip flexor stretching, thoracic spine rotation. These are the three areas that affect bike position most directly. A daily five-minute routine of hip flexor stretches, hamstring stretches, and thoracic rotations will do more for your fit stability than any piece of bike fitting technology.
Core stability. Planks, side planks, bird-dogs, dead bugs. These exercises build the stabilisation strength that lets you hold a position without dumping weight onto your hands or loading your lower back. You don't need heavy weights — bodyweight resistance is enough. The goal is endurance, not maximum strength. Hold planks for 45-60 seconds, do 10-12 reps of each exercise, focus on form.
Glute activation. Clamshells, single-leg glute bridges, lateral band walks. Weak glutes are one of the most common contributors to knee tracking issues, and they're something that gets worse with age and desk-based work. Two sessions a week of targeted glute work keeps the muscles that stabilise your pelvis on the bike firing properly.
This isn't optional extra credit. It's the foundation that makes your fit work. Phil Burt has said repeatedly that the best fit in the world won't survive a body that can't hold the position — and conversely, a body with good flexibility and core strength is forgiving of minor fit imperfections.
The Conversation That Never Ends
Bike fitting isn't a transaction. It's not something you buy once and file away. It's an ongoing relationship between you, your body, and your bike — and like any relationship, it needs regular attention.
The good news is that once you understand this, it becomes simple. Do your quarterly self-assessments. Keep your fit log. Change one thing at a time. Know which adjustments are yours to make and which need a professional. Do the off-bike work that keeps your body stable.
And when something hurts, don't ignore it. Pain on the bike is information. It's your body telling you that the position has drifted, that something has changed, that the fit needs to evolve.
If you want to get into the detail of how this works — the specific flexibility tests, the filming protocols, the adjustment sequences — we talk about it regularly in the Roadman community. Riders sharing their fit logs, comparing seasonal adjustments, troubleshooting each other's pain patterns. It's one of the most practically useful conversations we have. Join us at the Roadman Cycling community on Skool and bring your fit questions.
Because the best bike fit isn't the most expensive one. It's the one that keeps evolving with you.