Any question answered...

Helpful as always tester, much obliged.

Now to the brake situation, they bike has studs front and rear for what I assume to be a old style centre pull caliper.

I'm having trouble in my searches to determine between calipers that either mount to said studs or to the hole in the fork crown/brake bridge. Is there a keyword I'm missing? Or is there anything stopping me running modern cantilevered set-up?

You need to determine whether you have studs for cantilevers or centre pull calipers (like Mafac or Universal).
They're mounted a different distance apart and are different dimensions.
This page might help.
http://ruedatropical.com/2009/01/mafac-brake-bosses-v-canti-bosses/

Cantilevers you say...

Aha, makes more sense now. I've been looking as I had assumed they were mafac but I'm still struggling between the distinction of the nutted fitting at the top and the two studs. Different models?

Studs look like attached

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That stud looks like it's halfway between a cantilever and a centre pull position. Is it a 700C or 26×1⅜ wheel in a 27" fork by any chance?

I believe so as its a road frame and there's loads of clearance on the back too

I meant yes - the fork is 27" to match the 27" wheeled bike pictured with little wheels

.

What does a man do if he wants to run drop bars with a 3 speed nexus hub gear?

Friction bar end lever?

Here's the rear end, I'm finding it hard to find any mafac brakes that don't have the nut and bolt fitting for the fork crown/brake bridge. Am I missing something or are they just hard to come by?

You can also see the cable guide in the photo which is what originally made me think it was a traditional centre-pull.

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Maths people, I am stuck!

I have a formula D = (A*B*C)/10000 where all values are %.
If I know the ratio between A, B & C and I know value D, what formula do I use to individually calculate A, B & C?
I got twisted in knots yesterday and made my head hurt, even though I know I should be able to do this.
A:B:C = 2:47:51 if it helps!

Am I missing something or are they just hard to come by?

They're rarer than centre pull brakes with a single centre bolt fitting, simply because the latter are much cheaper to integrate into a frame. Check the parts diagrams, some of the Mafac brakes with a centre bolt fixing are just the stud mounted brakes with a bridge plate, so you can take them apart and use the arms on brazed on studs.

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Looking at the pictures of the frame and testers centrepulls,surely this means that the brake blocks will come into contact with the spokes as they are below the pivot studs. If As I think you have said the wheels are to small then this means you need brakes with the blocks above the pivot presumably cantis.

I know value D

What is it?

10000D = A × (47/2)A × (51/2)A

= A³ × (47 × 51)/(2 × 2)

so

A³ = (10000/((47 × 51)/(2 × 2))) × D

so

A = ∛(16.6875260743 × D)

Once you know the value of D, you can evaluate A, then B and C are simple fractions of that.

This place is wonderful.

D is a quality target, increasing over the years.
So I know D is 81% for FY16, 83% for FY17.
A, B and C are constituent sub targets.

so for D = 0.81, A = 2.38209453119

I think there's an error in your formula, if you want to put D = 81 then your divisor needs to be 100 not 10000 which would give

A = ∛(0.166875260743 × D)

= 2.38209453119

B = 55.9792214829
C = 60.7434105453

Of course, there is also an error in your formula if you want A+B+C=100 or A+B+C=81

Perhaps percentages confuse the issue? For this calculation we treat as normal numbers.

Example calculation

Sub targets = 70%, 80%, 90%
Total target = 50.4%

As 50.4 = (70*80*90)/10000

You've got me wondering if my ratio calculations are wrong.

A+B+C can be anything between 0 and 300.

Thank you for your help!

Very good point!

That makes things a bit more straight forward.

Thanks for the help.

Perhaps percentages confuse the issue?

They usually do :-)

What are they percentages of? Why are they in a fixed ratio? It's easier to tell whether you're doing the right maths (and the maths right) when you know what the numbers actually mean.

If I'm machining a 3:2:1 tooling block with sides A B and C, and I want to make sure it weighs D, a set of equations of the form

A=3C
B=2C
D=kABC

will work, and that's what you've got. I set k as the density and can find the lengths of the sides for any arbitrary target weight, but the last equation always simplifies to

D=6kC³

because the variables A B and C are not independent. It seems unlikely that your quality system would need 3 variables on the input side if they are not independent.

Let's say I want 90% of my headset covers to be saleable. There is a boring operation, an OD turning operation and a parting off height operation. The probability P₀ that the final product is right is the product of the probabilities P₁, P₂ and P₃ that each of the three operations is done right, assuming that they are completely independent of one another. If my boring is always 100% right but my turning and parting are only hitting 90%, I'm at 81% overall. There's no point looking to my borer for improvements, I need to talk to my turner and my parter to see whether one of them can get up to 100% or both can get to about 95%, or some other arrangement which gets the product of their two outputs up to 90%.

On the other hand, I could find that the boring is 90%, the turning is 90% and the parting off is 100%, but from inspection I find that the turning is always offset from the bore. That makes the ratio between turning and boring 1:1 but the turning is dependent on the boring. My success rate is 90% because everything with a good bore also has a good OD.

Sjs cycles may have something, there are companies that do drop bar shifters (sorry can't think of name right now) :)

So you bought that flying gate. Well done Sir!

sram 10 speed - when chain is on the big chainring, shifting to the biggest 2 sprockets, the chain doesn't sit properly on the lower jockey wheel, what's causing this?

Sorted, chain was slightly too short.

what's causing this?

The large angle between the chain line and the pulley centre plane. Shift to the little ring

Do cassette tools without the pin in the middle exist? I have a wheel with a solid axel and it's long removing the axel just to do cassette stuff.

My park tool shimano cassette tool does not have a pin.