Not All Bike Fits Are Created Equal

I've had a few bike fits in my time.  I think - I hope - I've just had one of the best.

It has taken my new Cervelo P2 Triathlon Bike from being "I'm not sure I can ride that comfortably", to pure "whhhoooo".  Also I suspect I've saved quite a few watts.  Free speed has to be good.

I've written about my bike fits several times, including a piece about Retul Fitting that was published in Scottish Cycling Magazine.

I like the way Retul works, using motion capture to accurately report the wangles through which your major joints were working, then the fitter's skill is used to optimise those angles.

It worked great for my Specialised Roubaix and my Parlee road bikes.  So far so good.

When I had my Parlee set up for triathlon with TT bars, the fit wasn't quite so great.  It needed tweaking by me and by coach Joe Beer.  He made some great changes just by looking at photos.
Unfamiliar roads
For my 2017 races I've bought a Cervelo P2.  Quite why I chose that bike is a blog post in itself, but I've been a bit worried.  Despite coming with a 'free' Retul fit - it didn't.  I was starting to doubt I would ever get comfy on the bike.

James Thomas at Sigma Sport
Imagine how delighted I was to sit on the bike yesterday and ride for an hour in comfort.  The roads were unfamiliar (we're having a short break down south) so I had to weave around sharp turns and inevitable pot-holes.  Through it all the P2 was like a dream.

The difference has been made by James Thomas, the bike fitter at Sigma Sport in Kingston on Thames.

It's a long story as to how I came to find James, but I'm pleased I did.  His 'secret system' is experience.

He fits on a jig - a fully adjustable bike-like machine - and once you're in the right position he transfers to the bike.  There's much much more to it than that, including video analysis, biomechanical assessment, a study of leg and other imbalances with orthotics and shims to correct.  It's the whole package.


For example, take a look at the pressure map of my backside on the saddle.  There's too much pressure on the left, which suggests I'm hanging off to the right.  Lower the saddle just 5mm and the pressure map equalised.  Result.

This whole process takes around three hours and costs, sit down for this, three hundred pounds.  Yes, it's a lot of money.  But think how much time you spend on your bike, how much money you spend on your bike, and you'll quickly realise it's worth every penny.

Cleats in right position & orthotic inside
So why did this work for me and, on this occasion, Retul didn't?  It's 'by the numbers' approach worked best when fitting me to a road bike.  I suspect that's because it had shed loads of data for middle-aged men in lycra, among whom my measurements would make me Mr Average.

Faced with a Time Trial bike, the 'by numbers' approach didn't suit me, because I wasn't using the bike to time trial.  Most TT events are around 10mile, yet I wanted a bike for mid to long course triathlon, 56 to 112 mile.  What's more, I wonder how many cyclists start TT when they're nearly 60?


I strongly suspect Retul, or the fitter, didn't have a wide enough data sample to find the angles best suited to me, my body and the type of riding I want to do.  Far from being Mr Average, as I was on the road bike, I was an outlier in their system.

One ride does not make a perfect fitting.  I might need to tweak a few things.  But at least I'm now comfortable and would be happy to head out on a 2-3 hour ride, something I would not have done on this bike before.

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