talking torques

[fatblokish]

Could someone please answer the folllowing two-part question.

1. How many torques does a 14 stone bloke, standing on a 120mm long allen key in a size eight shoe, apply to the central chainset tightening nut thingy of a 10 year old ultegra triple at an altitude of 75 m above sea level? (other relevant data may include the colour of the bike: red, and my favourite colour: red).

2. Is the answer to item 1. above sufficient?

ta

 

[RecordAceFromNew]

Too much, unless you and your bike are somewhere higher in orbit...

A 10 year old Ultegra is probably the FC-6400 for square tapered bb? If so according to Park it needs 305 - 391 lb-inches of torque, say 350 lb-inches. What you need is a 350 inch long white weightless allen key extension with pink dots and hang a pound of Tate & Lyle demerara at the other end.

If you must you can also hang your 74lb 50" flat-screen TV on the end of your 120mm (4.72 inches) allen key.

Hope it helps.

 

[Piemaster]

1. As its a size 8 boot - 77 ft lbs. If you had the equivilent metric boots (size 42) it would be 104Nm.
Stll a fair bit more than Park says

2. No. Unless you have rounded off the allen bolt, in which case, yes.

 

[2Loose]

Get a longer Hex key :-)

 

[subaqua]

you could always try WD40

 

[slowmotion]

If you are balancing daintily on the very end of the horizontal allen key (like a ballerina on her points) and if you are totally naked, the answer is 104.64 Nm.


BTW, I would attempt this feat of bike servicing in a very private place....

 

[byegad]

NOW I'm going to have nightmares.

 

[EdgEy]

Torque is simply distance from pivot multiplied by force.
14st = 88.9kg
Force of gravity = 9.81 newtons per kilogram
Distance 0.12m

0.12 * 9.81 * 88.9 = 104.7Nm, as slowmotion says.

Not quite sure what you intend to use this for though.

 

[slowmotion]

Torque is simply distance from pivot multiplied by force.
14st = 88.9kg
Force of gravity = 9.81 newtons per kilogram
Distance 0.12m

0.12 * 9.81 * 88.9 = 104.7Nm, as slowmotion says.

Not quite sure what you intend to use this for though.

Piemaster beat me too it. He deserves the credit. I merely suggested suitable "workwear".

 

[EdgEy]

Piemaster beat me too it. He deserves the credit. I merely suggested suitable "workwear".

Didn't quite catch that. Oh well.
I'm a Physics student and I wouldn't have thought of the 1kg bag of sugar on the end of a pole as a makeshift torque wrench. Clever idea.

 

[Piemaster]

Sometimes I hate being an engineer. I just can't stop myself from answering questions like the OP, even though I know one wasn't needed.

 

[asterix]

Can you just do it up till it feels right?