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  • KOPS and other golden bike fit rules. Do you?
  • RustySpanner
    Full Member

    Never been one for overanalysing road bike fit.

    I inhaled ‘Richard’s Bicycle Book’ in the early 80’s and have always used that as a basic fitting guide – he was right about everything else.
    🙂

    Shortarse and a sensitive little soul when it comes to set up, so all bikes have 170mm cranks, the latest one 165.

    All bikes set up on feel, until now.

    Just checked KOPS for the first time ever and it would appear I’m pretty much bang on on all the bikes.

    Seat height always just goes off feel.
    Claustrophobia vs rocking hips – you just know, right?

    Drop and stem length?
    Whatever feels right.
    Sporty bike – big drop, weight more on hands.
    Only out for a while, don’t care.

    All day bike?
    Experiment until you get the balance right.
    I try to find a position that I can maintain without using my hands, then try a few longer rides to balance the weight between arse and hands.

    Do you have any golden rules for bike setup that always work for you?

    Always wondered if a bike fit would be of use, even though I’m happy as I am.
    Benefitted greatly from an offroad coaching session which eliminated some bad habits I’d had for years, so open to new ideas.

    Which magic formula works for you?
    Was a bike fit worth it?

    Just pondering.

    aracer
    Free Member

    KOPS is BS – KB did this ages ago:

    http://www.sheldonbrown.com/kops.html

    RustySpanner
    Full Member

    That’s one of the pieces that made me post.
    🙂

    amedias
    Free Member

    basic fitting guide

    And there’s the nub of it, and all these systems, they have to have a starting point, a set of rules/guidelines to get you into a basic starting position that isn;t awful, everything else from there on is personal.

    personal anatomy
    personal preferences
    personal priorities
    personal tolerances

    That’s not to say a good fitter couldn’t help you improve your position*, but you need a good one who takes the time to understand you, how you work and what you’re after, not just plugs your numbers into a calculator.

    KOPS is one of those things that for normal upright bicycles and normal shaped people doing normal riding just happens to roughly turn out to be a good place to start.

    *improve for what? comfort, power, speed, it’s all compromises and the formula approach not only doesn;t take into account the personal bits, it’ll be weighted towards at least one of those things, which means there’s never a correct formula for all cases with all people.

    bencooper
    Free Member

    My golden rule for bike setup is to ride with an Allen key set and just try messing about with things to see what works. KOPS is nonsense, it’s cargo-cult bike fitting – just look at a recumbent, for instance.

    RustySpanner
    Full Member

    I’ve always set bikes up on feel.

    I’m just very surprised that the positions I’ve settled on all seem to conform to the KOPS rule.
    🙂

    KB’s piece is spot on re the mechanical relationship between knees, hips, feet and seat angle, but doesn’t enlighten much regarding the limits imposed on geometry by weight distribution and it’s effects on comfort.

    I assume that a recumbent position is different to a rotated upright position?

    holst
    Free Member

    On the night of the full moon align your bike precisely east-west on perfectly level floor, then use Uranus to determine the best setting for your saddle.

    timba
    Free Member

    My dad started my racing off in the 70s with 109% of my inseam measurement to determine saddle height (1967 research) and Greg LeMond developed a variation

    On my road bikes I start in my “normal” position on top of the bars and look down at the front wheel hub; the bars should hide the hub if the stem is the right length

    I still use both as starting points. IANAE

    nathb
    Free Member

    I setup my first road bike a couple of years blindly, and adjusted things as necessary over the course of a year until it was perfect.

    As I use the same saddles on all my bikes, on road/gravel/adventure bikes 2&3; I used the measurements off the first road bike to setup the new ones. Normally I don’t have to adjust anything from there onwards, but did drop the seat a couple of mm to compensate for longer crank arms on one of them.

    The only guide I’ve ever used was when setting up the missus’ road bike, this was a very good (imo): http://wheel-easy.org.uk/uploads/documents/RIDING%20%20POSITION.docx

    bencooper
    Free Member

    I assume that a recumbent position is different to a rotated upright position?

    It’s the same for leg length, but apart from that recumbents don’t have any hard and fast rules – basically because recumbents are much better for you biomechanically, so there’s no conflict between comfort and speed. Just adjust the bars for reach and a comfortable angle, adjust the seat for the same, and you’re done.

    thepodge
    Free Member

    I’m off for my first bike fit this evening, it’ll be interesting what I come back with.

    Main reason for going is no matter what I try I can never quite get comfy on the road bike so I figure it’d be 2 hours well spent.

    STATO
    Free Member

    Yes KOPS is not anatomically based, so you shouldn’t follow it as a hard and fast rule. From the article linked…

    Still, it is easy to see how the KOPS method can get by. It usually puts the rider in the range of correct fit, although in my experience, the more anatomical proportions vary from the norm, the more off the mark the KOPS method is.

    Its a starting point, and youll find if you are normally proportioned and buy a normal bike and just set the saddle to the right height you’ll probably be not far off, but it does needs to be adjusted over time to suit you and also your riding.

    Take a modern ‘enduro’ bike geometry, they have really steep seat tubes as they are designed for climbing seated and then standing descending, setting them up with KOPS on flat ground makes no sense.

    senorj
    Full Member

    Level saddle,heel on pedal and then a lot of fiddlling about.
    I’d hadn’t ridden a drop bar cycle in anger before 2012,it’s taken me 3 years to get it to feel lovely. (And that time to strengthen myself) Stem ,bar height,bar width, hood position etc…..

    greyspoke
    Free Member

    bencooper – Member

    I assume that a recumbent position is different to a rotated upright position?

    It’s the same for leg length, but apart from that recumbents don’t have any hard and fast rules – basically because recumbents are much better for you biomechanically, so there’s no conflict between comfort and speed. Just adjust the bars for reach and a comfortable angle, adjust the seat for the same, and you’re done.
    Interesting, I’ve only ridden a recumbent for 2 minutes. When pedalling hard on a recumbent, what do you push against? Is it your back/bottom on the seat, or do you also tug on the handlebars?

    bencooper
    Free Member

    No pulling on the bars, you push with your lower back against the seat. It should be just light steering input on the bars.

    That’s the bit that you have to unlearn when riding a recumbent – not to pull with your arms and down through your back, just push directly with your legs.

    On racing recumbents, when the seat angle gets less than 45 degrees, you do start to push a bit more with your upper back and shoulders as well, but it depends on BB height.

    thisisnotaspoon
    Free Member

    KOPS and 109% or heal on pedal all work for a first attempt, then just go for a ride and tweek it.

    Pain behind knee at the hamstring attachments, saddle too high or far back.

    Pain in front of knee (anywhere, or in general) saddle is too low or forward.

    Pain in the ITB saddle is too far forward.

    Pain above kneecap, cranks are too long.

    Most of those overlap, and you could have pain from badly fitting shoes/cleats, but all else being equal it’s pretty straightforward to just ride 5 miles, change soething, ride another 5, change something, ride another 5 etc.

    I always find my saddle needs to be a lot further forward than I think. With the added benefit that it tilts me forward into a more aero position too.

    amedias
    Free Member

    On my road bikes I start in my “normal” position on top of the bars and look down at the front wheel hub; the bars should hide the hub if the stem is the right length

    This is another one of those rules that gets trotted out, which really is another ‘accidental correlation of the average’ like KOPs.

    It doesn’t take into account variations in frame and fork geometry, or bar reach Vs stem reach, or any other aspects of positioning. Rules that relate bits of the bike which change regularly with fashion and trends (compare bar reach vs stem length on older bikes and these days, the relationship is almost completely inverted) are always at risk of becoming outdated very quickly.

    There’s also big variation between bike types and intended use. The ‘correct’ position on my fast road bike is nothing like the position I run on my audax bike, and even less like my tourer, they are all road bikes with drop bars, and all set up different, and they’re all correct, so put that in your formula and smoke it! 😉

    greyspoke
    Free Member

    Thanks. Racing – so I guess on a recumbent “aero” means horizontal, but for biomechanical efficiency there has to be enough bend at the hip, but the trade-off would lead to it being only just enough. (That is reading a bit into your comment about racing bike seat-back angles and bb height.) On upright bikes it is the other way round, aero means all scrunched up with the hips rotated forward as far as possible (particularly bearing in mind UCI rules about saddle nose position etc). If comfortable pedalling was your goal, that would probably get you to similar body angles whether recumbent or upright, just rotated.

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