Llewellyn...ditemi un po'

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sdg71

Guest
I believe there is no difference between TIG and Lugs in how the frame feels or reacts.
The tube diameters and the wall thickness and the length of the butt reinforcements will have effects on the frame's feel and reactions.
( and geometry)
A carefully built frame without cold setting so there are no in built stresses will give a sweeter riding frame.

Your last question. This question is a huge question. It will take 30 years to explain 30 years of experience
but to boil it down

I want to know your position data points. (attached drawing)
How to determine these data points? Some riders understand these, for some we must seek the position data with a biomechanical assessment (a big subject which I will not explain here),
also the position on the bike will change as the rider gets fitter, stronger, posture can change,
and then we all get older so things have to change.

"A bicycle is not a sofa"
Dario Pegoretti

all things have to be taken into the project
It is about the intended use for the bike.
and then I design the frame geometry to fit under you for the bike's intended use.
I select the materials.
I do use fragile tubes, there is no benefit in saving 100 grams and havijng a fragile frame, there is no performance gain. I long lasting bike for your hard earned dollars is important.
We speak and I explain my rational of design and choices.
Refer to attached sample CAD drawing.
Then the metal work will begin.

for me it is about
[FONT=&quot]A bicycle that gives them many years of enjoyable riding. So with each passing year, their Llewellyn bicycle gives them greater value. Thus they Cherish their Llewellyn. That pleases me.[/FONT]


kind suggestion to the moderators of this forum....please put this post in the homepage....post like this one are not easy to find in my modest opinion....
 

Dazza

Pignone
What is the weight limit for a rider between cutodian and cadenzia?
When, for you, a rider is heavy in kilograms?
I do not know if I explained well.

there is no definite line to cross from OS (Custodian) to XL (Cadenzia) size tubes.
I think XL tube sizes are best when the rider
a: the rider is more than 75kgs
and or
b: The frame size is bigger than 58cm seat tube.
c: If the rider is very powerful
d: Some riders want stiffness in the frame to feel confident.
e: Some times the rider's pedaling style and technique is an influence

It is important to match the fork to the rider
The fork blade thickness selection will vary to suit the rider's weight.
I use .8mm for light riders (-65kg) and .9mm (normal) and 1.00mm for heavier riders. +80kg
For very stiff forks I use Columbus MAX fork blades. (+ 95 kg)

It is also important to match the seat stays (posteriore verticale) to the rider and the ride feel desired.
I use 16mm, 17mm and 19mm diameter for the very big riders and track frames.

XL tubes (Cadenzia) is approx 20% greater stiffness then OS tubes (Custodian)

I explain to the client the direction and rational and we confirm so all understand the desired result.
 
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Dazza

Pignone
which is the difference between common xcr tubes and xcr for lugs?

When Mary Ann and I visited Caldanazzo, Dario thought it would be interesting to get Columbus to make XCr tubes to fit the new Cadenzia lug set (and to fit my XL Compact lug set, "Crescendo" model frame).

The existing XCr tube set was made for TIG welding and the down tube is 38mm which is too big for the lugs.
The reinforcements are too short for lugs.

Dario and I discussed dimensions and we agreed on drawings for the new tubes. I was not happy to use other brands of stainless (inox) tubes but I liked the Columbus product. Dario did some test brazing and the properties of the XCr was extremely good after silver brazing. Only 8% reduction.
Very good!
So Columbus made two sets for me, I made a Fixie frame which I took to NAHBS 2010. The other set Australian frame builder Ewen Gellie has used.
All is good.
I have a a raw untreated off cut of XCr tube out side my work shop, it looks still new after 16 months (refer to picture)

So the XL XCr for lugs is the correct size and has correct dimensions butt/reinforcements to use with lugs.

the problem is supply of the raw material to Columbus for them to make the tubes.
I have waited 16 months for my four sets of XCr here now.
Only four sets!

(I may use one XCr set for myself as an experiment and use to also test Dario's new fork when it is ready )


Columbus also plan to make OS XCr but when they will arrive is the ????
 

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Dazza

Pignone
whoops
I meant to say

I do not use fragile tubes, there is no benefit in saving 100 grams and havijng a fragile frame, there is no performance gain. I long lasting bike for your hard earned dollars is important.

You are right...



I fully agree with Dario.



Basically I agree this strategy.
Practically I felt enormous differences between frames with 100-200g of weight range. Maybe the biggest part of these differences must be the geometry, but even in the cases the geometry was the same traditional one with similar angles, I felt big differences while climbing "fuorisella", sorry but I don't know how do you say when you ride without being sat on the saddle.
Approaching the discussion following this concept, what is the weight of the lugs you need to add for building a lugged frame? (this is only a curiosity)

Tnx a lot Dazza for your kindly and friendly answers.

And last but not least, my best compliments for your lugged frames.

You explain well.

Cadenzia lugs unmodified in a raw state 170gr

however, with TIG you must use a heavier head tube and also seat tube with the reinforcement at the seat post binder.
There is a lot in tube selection.

I find it difficult to find
'enormous differences between frames with 100-200g of weight range."

The differences between bicycles is hard to define, there are so many variables in geometry, materials, tube dimensions, parts and wheels, tyres on the bikes.

I always ask the rider if their bike feels faster after they tip put 200ml of water from their bottle?
An empty water bottle weighs 85 grams

I have been at testing at an Australian Altitude training camp at Livigno Italy, repeated timed efforts on the climbs and 500 grams added to complete body/bike weight and times could not be detected. There was no consistency at all with time and weight.
Science and maths will tell us the theory, but in the application outside it is hard to detect.
The differences was all down to the rider's form and power on that effort.
As long as the bike is not a boat anchor
and all is running smooth
and good tyres
and bike feels nice
then you ride fast
with enjoyment

I am pleased you are enjoying my responses.
I tell it as I see it and how I have experienced it.
 
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ciofecca gialloblù

Apprendista Velocista
16 Maggio 2009
1.392
94
Verona
Visita sito
Bici
de fero
Thank you every one.
I am pleased I am can provide entertainment
with reason
I cannot always devote a lot of time to forums
life is short
and I have lots of projects

Darrell your presence is certainly valuable, but you're certainly right in claiming priority to other projects, which involve the personal and professional life.
The attention that you gave us, I think I speak for all those who have spoken, has far exceeded our expectations.
When you log in you are always welcome of course. o-o
Hello and good day.

Roberto
 
S

sante pollastri

Guest
in my opinion a steel frame need of a steel fork,if this material is good for a frame,it is good for a fork too.
columbus max fork is,for me,the best one.
how much is important the stem bar lenght?
if you have to build a frame,e.g. 56x56,do you prefer an 11 cm lenght or 12?
thankso-o
 

Dazza

Pignone
in my opinion a steel frame need of a steel fork,if this material is good for a frame,it is good for a fork too.
columbus max fork is,for me,the best one.
how much is important the stem bar lenght?
if you have to build a frame,e.g. 56x56,do you prefer an 11 cm lenght or 12?
thankso-o
Steel forks, I agree are the best.

It could be 110mm or 120mm (I prefer millimeters) depending of the handle bar curve. The sum of these two dimensions may be the same!

The stem length has to take into account the shape of the handle bar,
the distance of the handle bar curvature is variable
for example
Deda Newton Shallow (Italian Classic) is 94mm
Nitto Mod 104 is 79mm
and every brand and model of handle bar is different.
I measure the bars to be used and keep the data, example Cinelli 66 is 95mm. Even the tilt of the bars will change the reach dimension.

So a 110mm stem with big curve handle bar (Nitto) is going to have longer reach to the curves and brake lever hoods
than a 120mm stem with Newton shallow bars.

I plot where the hand will be in the drop curve and on the lever hoods.
Then plot the dimension back from the there to the handle bar stem centre. Then the stem length is the dimension to the chosen place of the steering axis.

Position first.
Feet, hands and bum.
The frame and bike parts go under this.
 

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Dazza

Pignone
What do you mean about very powerful?
I want to understand.
For example, approximately: A very powerful rider, how many watts he must have at the Onset Blood Lactate Accumulation?
Can you explain what you mean?

I do not have a number.
It is general observation and comment on the rider.
There are riders who never use bigger than 42 x 17 on the flat roads
and are in 30 x 25 as soon as the road becomes 5% for 200 meters.
This is fine.
I am getting close to this :cry

Some riders can thump 53 x 15 at 90 rpm = 40kmp + on the flat roads
and then grunt 53 x 14 at 50kmph for 5 mins

It is an estimation as it is too difficult to determine with numbers.

Some heavy riders 90kgs may not be powerful for very long durations but when they stand on the pedals there is a lot of force swinging on the pedals when this rider grunts in a sprint or up a short sharp hill.
 
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L

loscaligerocancellato

Guest
I do not have a number.
It is general observation and comment on the rider.
There are riders who never use bigger than 42 x 17 on the flat roads
and are in 30 x 25 as soon as the road becomes 5% for 200 meters.
This is fine.
I am getting close to this :cry

Some riders can thump 53 x 15 at 90 rpm = 40kmp + on the flat roads
and then grunt 53 x 14 at 50kmph for 5 mins

It is an estimation as it is too difficult to determine with numbers.

Some heavy riders 90kgs may not be powerful for very long durations but when they stand on the pedals there is a lot of force swinging on the pedals when this rider grunts in a sprint or up a short sharp hill.

then, of course, a rider, sprinter, who has peak power needs of a rigid frame.
 

Dazza

Pignone
then, of course, a rider, sprinter, who has peak power needs of a rigid frame.

yes
and the tests and the science shows that flexy frames do not soak up energy more than stiff frames
they do not heat up dissipating energy, this is a huge myth
but the rigid frame will handle and track better
giving confidence to the rider
thus it feels nice to ride!

but importantly the front wheel and the back wheel stay in better plane/alignment if the frame is rigid under high wattage stress
(Stress = the force, Strain = the deflection)
so rolling resistance of the wheels/tyres is lower as the wheels track better.
If the frame bends a lot the wheels are not in the same plane
and rider counter steers the bike with each pedal stroke

This is what riders call responsive when there is less input to direction/handle bars to the pulse on the pedals.
it feels like the bike jumps to the pedal stroke.

An Extreme example is the kilo rider, when they start they generate over 2,500 watts for a few seconds
and the frame distorts huge amounts, but the wattage drops as the pedal rpm increases but it is still WOW. Still over 1000 watts.

1000 + watts on a frame that is as rigid as over cooked pasta (pasta just like how the French cook pasta :cry )
is terrible.
For a road frame we have to ride for many kilometers for a long time
so harshness must be reduced
All road frames are a compromise of rigidity for good feel and responsiveness with flex for comfort
a good builder designs the frame to find this balance for the particular individual rider


I know steel is the best for this ;-)
weight is less important
but the market just sells weight as the most valuable item
 
L

loscaligerocancellato

Guest
please
for our Italian friends
[url]http://translate.google.com.au/?hl=en&tab=wT#[/URL]
and do not be shy

per quelli un po' pigri e restii ad usare il traduttore di google:


e le prove e la scienza dimostra che il telaio flexy non assorbire più energia che il telaio rigido
non riscaldare la dissipazione di energia, questo è un grande mito
ma il telaio rigido consente di gestire e tenere traccia migliore
dare fiducia al pilota
così ci si sente bello da guidare!

ma soprattutto la ruota anteriore e ruota posteriore soggiorno in una migliore aereo / allineamento se il telaio è rigido sotto stress alto wattaggio
(stress = la forza, la deformazione Strain =)
così la resistenza al rotolamento delle ruote / pneumatici è inferiore, come le ruote pista migliore.
Se il telaio si piega molto le ruote non sono sullo stesso piano
e contrastare il pilota dirige la moto ad ogni colpo di pedale
Questo è ciò che i piloti chiamano reattivo quando c'è meno input di direzione / manubrio per il polso sui pedali.
ci si sente come la moto salta la corsa del pedale.

Un esempio estremo è il pilota kilo, quando cominciano essi generano più di 2.500 watt per pochi secondi
distorce e la cornice di enormi quantità, ma la potenza scende come il pedale i giri aumentano, ma è ancora WOW. Ancora più di 1000 watt.

1000 + watt su un telaio che è così rigida come sulla pasta scotta (pasta, proprio come la pasta come cuoco francese)
è terribile.
Per un telaio da strada, dobbiamo correre per diversi chilometri per un lungo periodo
così asprezza deve essere ridotta
Tutti i telai da strada sono un compromesso di rigidità per stare bene e la reattività con la flessione per il massimo comfort
un buon costruttore disegna il telaio per trovare questo equilibrio per il pilota di singole persone

So che l'acciaio è il migliore per questo
il peso è meno importante
ma il mercato vende il proprio peso come elemento più prezioso
 

Mardot

Velocista
25 Febbraio 2008
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Cadenzia lugs unmodified in a raw state 170gr

however, with TIG you must use a heavier head tube and also seat tube with the reinforcement at the seat post binder.
There is a lot in tube selection.

I find it difficult to find
'enormous differences between frames with 100-200g of weight range."

The differences between bicycles is hard to define, there are so many variables in geometry, materials, tube dimensions, parts and wheels, tyres on the bikes.

I always ask the rider if their bike feels faster after they tip put 200ml of water from their bottle?
An empty water bottle weighs 85 grams

I have been at testing at an Australian Altitude training camp at Livigno Italy, repeated timed efforts on the climbs and 500 grams added to complete body/bike weight and times could not be detected. There was no consistency at all with time and weight.
Science and maths will tell us the theory, but in the application outside it is hard to detect.
The differences was all down to the rider's form and power on that effort.
As long as the bike is not a boat anchor
and all is running smooth
and good tyres
and bike feels nice
then you ride fast
with enjoyment

Well, basically I agree with your approach in terms of philosophy.

But I have some remarks: if I have a steel frame of 1450g, like my frame for example, and you add 500g to the bike as an external pack, like you did in Livigno, this is not the same situation of having a frame of 1950g, this is sure.

The behaviour of the bike is mainly driven by the frame, not by the bike entirely, so if you have 1500g of frame and you add 300g (plus 20% of the frame wheight) you would really have big differences, both climbing and descending at high speed, because they are completely different frames.

The weight of 300g globally distributed on the frame implies enough to change your feeling with your bike.

Probably if you have 300g of difference between two frames, they are built with different tube series, as well.

Do you agree my remarks or am I overlooking some other aspects?

I am pleased you are enjoying my responses.
I tell it as I see it and how I have experienced it.
Tnx Dazza for your time, I'm really enjoining. o-o
 
S

sante pollastri

Guest
Well, basically I agree with your approach in terms of philosophy.

But I have some remarks: if I have a steel frame of 1450g, like my frame for example, and you add 500g to the bike as an external pack, like you did in Livigno, this is not the same situation of having a frame of 1950g, this is sure.

The behaviour of the bike is mainly driven by the frame, not by the bike entirely, so if you have 1500g of frame and you add 300g (plus 20% of the frame wheight) you would really have big differences, both climbing and descending at high speed, because they are completely different frames.

The weight of 300g globally distributed on the frame implies enough to change your feeling with your bike.

Probably if you have 300g of difference between two frames, they are built with different tube series, as well.

Do you agree my remarks or am I overlooking some other aspects?


Tnx Dazza for your time, I'm really enjoining. o-o

i think that is almost impossible feel differences between two identical frames but of different tube series.
a good bike,in my opinion,weight more than 8 kg.