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Emanuel Berg[_2_] February 27th 18 01:15 AM

1p crank
 
Here is a good image of the/a
one piece crank [1].

I have a couple of such from Japan and Taiwan
and they seem to be 100% interchangeable down to
the last washer.

What I can see they are also identical to the
one depicted, only sometimes there is a big
washer/spacer between the chainring/sprocket
and the stationary cone, and they have a large
dustshield between the adjusting cone and
the lockwasher.

The locknut is sometimes 31mm which is a rare
combination spanner size. More often they are
32mm tho.

[1] http://user.it.uu.se/~embe8573/bike/1p-crank.jpg

--
underground experts united
http://user.it.uu.se/~embe8573

AMuzi February 27th 18 01:40 AM

1p crank
 
On 2/26/2018 6:15 PM, Emanuel Berg wrote:
Here is a good image of the/a
one piece crank [1].

I have a couple of such from Japan and Taiwan
and they seem to be 100% interchangeable down to
the last washer.

What I can see they are also identical to the
one depicted, only sometimes there is a big
washer/spacer between the chainring/sprocket
and the stationary cone, and they have a large
dustshield between the adjusting cone and
the lockwasher.

The locknut is sometimes 31mm which is a rare
combination spanner size. More often they are
32mm tho.

[1] http://user.it.uu.se/~embe8573/bike/1p-crank.jpg


Crank shown is different, being 28tpi. The others are 24tpi.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971



Emanuel Berg[_2_] February 27th 18 01:55 AM

1p crank
 
AMuzi wrote:

Crank shown is different, being 28tpi.
The others are 24tpi.


OK, that's a pretty important difference :)

No I was thinking more as a guide to putting
them together...

--
underground experts united
http://user.it.uu.se/~embe8573

Emanuel Berg[_2_] February 28th 18 06:47 AM

1p crank
 
AMuzi wrote:

Crank shown is different, being 28tpi.
The others are 24tpi.


Is this the same old English "Imperial" system?

24tpi = 24G Whitworth 55 deg?

Sure looks like that...

And yes, I counted the Taiwanese crank has
6 threads for 4/16" or 24tpi as you say.

--
underground experts united
http://user.it.uu.se/~embe8573

AMuzi February 28th 18 07:38 PM

1p crank
 
On 2/27/2018 11:47 PM, Emanuel Berg wrote:
AMuzi wrote:

Crank shown is different, being 28tpi.
The others are 24tpi.


Is this the same old English "Imperial" system?

24tpi = 24G Whitworth 55 deg?

Sure looks like that...

And yes, I counted the Taiwanese crank has
6 threads for 4/16" or 24tpi as you say.


No.
They are American SAE 60-degree thread.

p.s. You need a set of thread gauges:
http://toolguyd.com/blog/wp-content/...itch-Gauge.jpg

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971



Emanuel Berg[_2_] February 28th 18 07:53 PM

1p crank
 
AMuzi wrote:

No. They are American SAE 60-degree thread.

p.s. You need a set of thread gauges:
http://toolguyd.com/blog/wp-content/...itch-Gauge.jpg


I have one, but only for Metric 60 and
Whitworth 55.

The Whitworth 55 24G blade looks like a very
good fit to the crank thread but having it
perpendicular and holding the crank and
thread gauge to a light bulb I do see some
light shining thru so perhaps that's it?

BTW why are the Japanese and Chinese/Taiwanese
using a US system? Not that there is anything
wrong with that! Only the English system is
everywhere I can understand because of them
pioneering manufacture/industrialism...

--
underground experts united
http://user.it.uu.se/~embe8573

Emanuel Berg[_2_] February 28th 18 08:02 PM

1p crank
 
The Whitworth 55 24G blade looks like a very
good fit to the crank thread but having it
perpendicular and holding the crank and
thread gauge to a light bulb I do see some
light shining thru so perhaps that's it?


I just now did the same thing with an M8 bolt
and the metric 1.25 pitch blade from the same
thread gauge and there were light there as
well, just a little but still, so perhaps one
shouldn't use that method when in doubt...

--
underground experts united
http://user.it.uu.se/~embe8573


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