will i need to move the front mech...

[alecstilleyedye]

if i go from a 52 teeth chainring to a 53?

 

[S-Express]

Depends how much clearance there already is.

 

[Sharky]

I knew there was a reason for learning geometry at school now after 48 years I've found it.

Cirmcumference = 2 pie R
so R = Circumference / 2 pie
so 53*0.5 / 2* pie - 52 *0.5 /2* pie = "not a lot"

 

[S-Express]

Probably. About 2mm if my sums are correct.

Your sums would only be correct if the mech is in the right position to start with.

 

[Yellow Saddle]

Geometry is very clear in this. It says maybe.
Precise science aside, surely, if you have enough tech savvy to remove and replace a chainring, you have enough skills to loosen a FD and move it up a fraction?

 

[alecstilleyedye]

replacing the whole crankset and bb. probably have mi5 on my case as it says isis drive on it...

 

[fossyant]

You'll likely have some adjustment with a new cranks for shifting but you might just get away with not moving the mech up if you have enough gap.

 

[ianrauk]

I knew there was a reason for learning geometry at school now after 48 years I've found it.

Cirmcumference = 2 pie R
so R = Circumference / 2 pie
so 53*0.5 / 2* pie - 52 *0.5 /2* pie = "not a lot"

 

[Ajax Bay]

I knew there was a reason for learning geometry at school now after 48 years I've found it.
Cirmcumference = 2 pie R
so R = Circumference / 2 pie
so 53*0.5 / 2* pie - 52 *0.5 /2* pie = "not a lot"

There was a reason, @Sharky - so why didn't you? Number of teeth is not 'r'.

Radius of a '53' is 108mm. Radius of a 52 is therefore 108 x52 /53 (= ~106mm).
Hence @User 's 2mm recommendation, with the probably / "if the mech is in the right position to start with" caveat.

 

[cyberknight]

@vernon ?

 

[Dogtrousers]

There was a reason, @Sharky - so why didn't you? Number of teeth is not 'r'.

Radius of a '53' is 108mm. Radius of a 52 is therefore 108 x52 /53 (= ~106mm).
Hence @User 's 2mm recommendation, with the probably / "if the mech is in the right position to start with" caveat.

@Sharky 's forumula for the radius of a 53 is pretty good I thought: 53*0.5 / 2* pie gives 4.21" or 107.1 mm. The overall delta formula 53*0.5 / 2* pie - 52 *0.5 /2* pie = "not a lot" gives a delta of 0.08" or 2mm - in line with what @User suggested.

 

[Sharky]

@Sharky 's forumula for the radius of a 53 is pretty good I thought: 53*0.5 / 2* pie gives 4.21" or 107.1 mm. The overall delta formula 53*0.5 / 2* pie - 52 *0.5 /2* pie = "not a lot" gives a delta of 0.08" or 2mm - in line with what @User suggested.

I know it was 48 years since I left school. but I thought I was nearly the same as @User.

Cheers Keith

 

[Dogtrousers]

I know it was 48 years since I left school. but I thought I was nearly the same as @User.

Cheers Keith

Why do we like pie so much? It's irrational.

 

[Tim Hall]

Why do we like pie so much? It's irrational.

The volume of a flat bread, of Italian origin,(typically topped with tomato, cheese and other savoury items and baked in an oven) thickness "a", radius "z" is given by the formula pizza.