Author Topic: Identifying Speedo & Rev Counter  (Read 9145 times)

Online bsa-bill

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Re: Identifying Speedo & Rev Counter
« Reply #15 on: 14.07. 2010 08:24 »
Quote
I guess the "maths" is just not interesting.

I had a good look at them ( always liked maths at school ) getting to be a lost art these days Richard what with spreadsheets and calculators.
but handy to have the mental agility learned pre chips
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Offline Goldseeker

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Re: Identifying Speedo & Rev Counter
« Reply #16 on: 14.07. 2010 09:46 »
I guess the "maths" is just not interesting.

They were indeed interesting Richard and I will be testing my maths skills once I get my ageing head around them.  *smiley4*

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Offline Goldseeker

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Re: Identifying Speedo & Rev Counter
« Reply #17 on: 14.07. 2010 09:57 »
Hi there

The chronometric refers to reference to a clock. The clock - escapement movement is powered by the drive cable. The purpose of the clock movement is to time the movement of a meshing gear which mates with another gear driven in relation to the speed of the drive cable. The meshing gear is in contact with the drive gear for 0.6 of a second. Thus the pointer moves in increments of 0.6s. The faster the speed  the further the pointer moves in the 0.6s it is engaged. This all means that the pointer jumps to a new reading every 0.6s. The movement in these speedos is a masterpiece of engineering. These speedos contain 100s of parts in comparison with the modern magnetic ones.

Hope this is clear enough?

Stu

Stu, very interesting, explains why the needle jumps as normal. However I think that mine may be jumping a bit more than it should. I will look at it again with a second pair of eyes as it was not easy trying to keep one eye on the dial and the other on the test meter.

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Online flashblack

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Re: Identifying Speedo & Rev Counter
« Reply #18 on: 18.07. 2010 16:22 »
Just for the record, this is mine in action: --- old link removed, correct link on my next post ---
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Offline Goldseeker

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Re: Identifying Speedo & Rev Counter
« Reply #19 on: 18.07. 2010 22:15 »
Just for the record, this is mine in action: http://www.youtube.com/watch?v=c1dqq2Kt2ko  (ftp://http://www.youtube.com/watch?v=c1dqq2Kt2ko)

Link doesn't work for me  *dunno*
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Re: Identifying Speedo & Rev Counter
« Reply #20 on: 19.07. 2010 11:04 »
Not just you Col, I can't get the link either.
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Re: Identifying Speedo & Rev Counter
« Reply #21 on: 19.07. 2010 15:40 »
Right i`ll try again: http://www.youtube.com/watch?v=c1dqq2Kt2ko

I think i`ve cracked it this time (should have done it before a beer!)
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Re: Identifying Speedo & Rev Counter
« Reply #22 on: 19.07. 2010 18:00 »
Right i`ll try again: http://www.youtube.com/watch?v=c1dqq2Kt2ko

I think i`ve cracked it this time (should have done it before a beer!)

Thats better  *smile*

I greased the cable this morning and now mine works very similarly to yours, result.  ;)

Col.
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