bike positioning help please

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horizon
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Re: bike positioning help please

Post by horizon »

531colin wrote:
horizon wrote:............

But to answer colin531's point: I also felt (like cycle tramp) that KOPS might come later..................


OK...if KOPS comes later, that means either there is something more important than getting the saddle set right in relationship to the pedals, or there is a better way of doing it....could you share your thoughts with us?

I'm not saying that KOPS is a magic bullet, but I don't see any point in knocking KOPS if you are not going to replace it with something better.


I'm not knocking KOPS (or any rules of thumb etc). I was saying that the OP just needed to wiggle everything about a bit and not overdo the high gears. My impression was that he felt that his pain and discomfort would be cured by applying a formula but IMV no perfect fit was going to help him until he had got himself comfortable. I'm no expert on this but someone thrashing out a 17 mile commute in cold weather in cleats on drops that he isn't used to has easier options to explore first (like easing off!). I do believe strongly in getting it right however, of which KOPS etc are a part.
When the pestilence strikes from the East, go far and breathe the cold air deeply. Ignore the sage, stay not indoors. Ho Ri Zon 12th Century Chinese philosopher
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531colin
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Re: bike positioning help please

Post by 531colin »

Fair enough. 34 miles is a bit of a push in addition to a days work.
How about a one way commute?....depends on public transport, or leaving the car at work, I guess.
samsbike
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Re: bike positioning help please

Post by samsbike »

I am going to persevere for a bit, I really don't want another mistake. Next option is a uncut fork, but I need to get my basic position right first.
cycle tramp
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Re: bike positioning help please

Post by cycle tramp »

531colin wrote:how is it helpful to rubbish KOPS and put nothing in its place?
How is the riding position on a recumbent significant when setting up an upwrong?
For a touring cyclist, where you put the saddle has a lot to do with weight distribution between hands, feet, and backside ....its not like sitting in a deckchair.


Two very good points there.. everyone is different, of course, but the main things i tend to check for my own personal comfort on a bike.. includes, flat pedals, without clips, (because i am one of these people who can fall off a bike on a level, clean road, in good riding conditions, all by myself) 170mm crank length, a distance of 91.5 cm or there abouts (which is my inside leg measurement from bare foot to crouch times by the 1.09 thing).. which means that my leg has a slight bend at the end of the pedal stroke, and if i straighten my leg my ankle just dips under the pedal spindle.. handle bars level with the saddle, and a distance from the saddle to the handlebar itself of; the length of my forearm with my fingers out stretched, plus my other hand turned at 90 degrees to my forearm, to my index finger... i ride with straight bars and ergo bar grips.. feel free to shout if i've got it wrong..
It's time to go :-)
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531colin
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Re: bike positioning help please

Post by 531colin »

cycle tramp wrote:................ 170mm crank length, a distance of 91.5 cm or there abouts (which is my inside leg measurement from bare foot to crouch times by the 1.09 thing).. which means that my leg has a slight bend at the end of the pedal stroke, and if i straighten my leg my ankle just dips under the pedal spindle.. handle bars level with the saddle, and a distance from the saddle to the handlebar itself of; the length of my forearm with my fingers out stretched, plus my other hand turned at 90 degrees to my forearm, to my index finger... i ride with straight bars and ergo bar grips.. feel free to shout if i've got it wrong..


Yes, I do all that (well, not those numbers, the procedure)
but in addition, it matters to me how far behind the BB axle the saddle is....I can have the right reach from saddle to bar, but if they are both "too far forward relative to the BB spindle" by less than an inch, I'm uncomfortable.....ymmv!
Ayesha
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Re: bike positioning help please

Post by Ayesha »

I went for a bike fitting session.

Firstly, he set my shoe cleat position to my second metatarsel.
Then he set the saddle height to get good upper leg angles.

He had me riding my bike for half an hour on a Tacx Bushido at 200 Watts absorption at about 85 rpm.
He took 30s or so of high speed video, and then analysed the footage to determine if my knee was coming over the pedal spindle. A 'Dynamic' test.

The second run was at 240 Watts. There was a slight change in KOPS cus my backside had drifted forward, cus it felt easier to get the power on 'the rivet'.
The bike was set up to get KOPS at 240 Watts. This meant that when I was 'cruising' my knee was very slightly behind the pedal spindle.

After much testing. A grid of nine saddle positions ( 3 fore/aft + 3 height positions ) were tested.

A 'blind' test was done for all nine where I couldn't see the Wattage readout. I was asked to ride at the same RPE for each test, with the guy shifting the saddle while I was stood up pedaling.

The optimum was finalised.

£140 WELL SPENT.
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NATURAL ANKLING
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Re: bike positioning help please

Post by NATURAL ANKLING »

Hi,
Ayesha wrote:I went for a bike fitting session.
Firstly, he set my shoe cleat position to my second metatarsel.
Then he set the saddle height to get good upper leg angles.
He had me riding my bike for half an hour on a Tacx Bushido at 200 Watts absorption at about 85 rpm.
He took 30s or so of high speed video, and then analysed the footage to determine if my knee was coming over the pedal spindle. A 'Dynamic' test.
The second run was at 240 Watts. There was a slight change in KOPS cus my backside had drifted forward, cus it felt easier to get the power on 'the rivet'.
The bike was set up to get KOPS at 240 Watts. This meant that when I was 'cruising' my knee was very slightly behind the pedal spindle.
After much testing. A grid of nine saddle positions ( 3 fore/aft + 3 height positions ) were tested.
A 'blind' test was done for all nine where I couldn't see the Wattage readout. I was asked to ride at the same RPE for each test, with the guy shifting the saddle while I was stood up pedaling.
The optimum was finalised.
£140 WELL SPENT.

All good, can you be more specific on what relationship the foot has with the pedal spindle :?:
That is where a pro fitter places the foot metatarsel to the pedal spindle.
Thanks,
NA Thinks Just End 2 End Return + Bivvy - Some day Soon I hope
You'll Still Find Me At The Top Of A Hill
Please forgive the poor Grammar I blame it on my mobile and phat thinkers.
Ayesha
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Re: bike positioning help please

Post by Ayesha »

NATURAL ANKLING wrote:Hi,
Ayesha wrote:I went for a bike fitting session.
Firstly, he set my shoe cleat position to my second metatarsel.
Then he set the saddle height to get good upper leg angles.
He had me riding my bike for half an hour on a Tacx Bushido at 200 Watts absorption at about 85 rpm.
He took 30s or so of high speed video, and then analysed the footage to determine if my knee was coming over the pedal spindle. A 'Dynamic' test.
The second run was at 240 Watts. There was a slight change in KOPS cus my backside had drifted forward, cus it felt easier to get the power on 'the rivet'.
The bike was set up to get KOPS at 240 Watts. This meant that when I was 'cruising' my knee was very slightly behind the pedal spindle.
After much testing. A grid of nine saddle positions ( 3 fore/aft + 3 height positions ) were tested.
A 'blind' test was done for all nine where I couldn't see the Wattage readout. I was asked to ride at the same RPE for each test, with the guy shifting the saddle while I was stood up pedaling.
The optimum was finalised.
£140 WELL SPENT.

All good, can you be more specific on what relationship the foot has with the pedal spindle :?:
That is where a pro fitter places the foot metatarsel to the pedal spindle.
Thanks,


The joint of the second metatarsel and phalanges is directly above the bolts on an SPD.
On an SPD-SL, there is a little notch in the plastic.

You can use the shoe's box to do the marking up.
Estimate the packing required behind the heel ( Thickness of shoe, usually about 4mm ). Put it between heel and box end wall and make a mark across the box floor in line with the metatarsel-phalanges joint.
Put shoe in box on its side and make a mark on the sole in line with the mark in the box.
Bolt cleats in as appropriate.

With SPDs and SPD-SL cleats, there is room for a little adjustment. With shoeplates on Olde Worlde shoes for quill pedals, there's not cus they're nailed into position. :D
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NATURAL ANKLING
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Re: bike positioning help please

Post by NATURAL ANKLING »

Hi,
The metatarsels joint is where to the pedal spindle? I dont have cleats at all.
Metatarsels joint inline with pedal spindle or behind or in front :?:
Sorry if I did not make myself clear.
Thanks,
NA Thinks Just End 2 End Return + Bivvy - Some day Soon I hope
You'll Still Find Me At The Top Of A Hill
Please forgive the poor Grammar I blame it on my mobile and phat thinkers.
rogerzilla
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Re: bike positioning help please

Post by rogerzilla »

It all depends on how much you want to use your calves. I have the cleats very far forward and use my calves a lot, because they're slightly longer than normal when compared to my thighs. Generally sprinters have the cleats further forward than rouleurs.
samsbike
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Re: bike positioning help please

Post by samsbike »

I thought I would update this thread.

Spookly, Colin was pretty much spot on with most of his observations. Since the thread started I moved my saddle back in 0.5cm increments. I did try 1cm in the beginning but it just did not work. Since Sunday I have been riding with another 1cm back (ie. total 1cm from where I started). I have dropped the saddle slightly to compensate and it feels OK.

I did manage to hurt both my knees when I left the saddle too high last week and learnt that I tend to drop my toes when the saddle is too high. From memory, I tend to drop my heels when the saddle is too low.

What I am confused about is the reach. Now when I do the elbow against saddle and index finger to the bars there is a gap of 0.5cm. However on the hoods the front hub is still obscured. The hub was obsured when the saddle was 0.5cm more forward so I am not sure what I am doing differently.

My shoulder ache is still there but I am managing it with stretches and it doesn't last that long so I am happier. If would be good to be pain free but its a lot better. I need to work more on my core (and I have been doing the plank exercise)and do focus on keeping my hands light.

Once I settle in this current position I may end up trying some bars with longer reach just to see if I am more comfortable as I am not that comfortable in the drops, but that could be due to the bars being a lot lower (well around 4cm) than the saddle.
rfryer
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Re: bike positioning help please

Post by rfryer »

I like the methodology described here.

Basically, it's all about positioning the saddle such that your normal riding position, when pedalling with your normal technique, results in minimal weight being carried by the arms. Once you've achieved this, you can simply swing your arms forward and get a feeling for where the arms ought to be.

Unfortunately, to use this at home, I think you need to already have a good understanding for what "feels" right.
samsbike
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Re: bike positioning help please

Post by samsbike »

rfryer wrote:I like the methodology described here.

Basically, it's all about positioning the saddle such that your normal riding position, when pedalling with your normal technique, results in minimal weight being carried by the arms. Once you've achieved this, you can simply swing your arms forward and get a feeling for where the arms ought to be.

Unfortunately, to use this at home, I think you need to already have a good understanding for what "feels" right.


cheers I didnt get that from that I will try it as I settle into the position.
JohnW
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Re: bike positioning help please

Post by JohnW »

Can I make a suggestion to the moderators, or whoever is responsible for these things, that this thread becomes a "permanent", or "sticky" or whatever those who know what they're talking about call it, as something worth hanging on to, and being readily accessible for future Forum members/users? These are questions which are asked so very frequently and a really valuable resource.

People are always asking the questions - not only on the Forum, but cyclists who are new to cycling, recent additions to our section, novice cyclists - and being able to point them to something like this is a real boon.

It's true that the "rules" get us very close to the optimum, and that some of us will fine-tune after that, but they do help to avoid newcomers getting it all horribly wrong.

To add my personal two-pennorth - after over 50 years of serious adult cycling, I'd say that colin531's advice and input is well informed and worth heeding - he clearly has experience both as a long-term, high mileage cyclist himself, and as a professional bike-builder. And no, I don't know him, never met him (as far as I know - although he may have served me at Spa sometimes) and I'm not flannelling him.

And a final question.............is it ever going to stop raining?
Vorpal
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Re: bike positioning help please

Post by Vorpal »

JohnW wrote:Can I make a suggestion to the moderators, or whoever is responsible for these things, that this thread becomes a "permanent", or "sticky" or whatever those who know what they're talking about call it, as something worth hanging on to, and being readily accessible for future Forum members/users? These are questions which are asked so very frequently and a really valuable resource.


It has been added to the 'too good to lose' section viewforum.php?f=25
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