What is 1/2 inch pitch?

Also sprach Carl <[email hidden]>:

Quoted message said:

Hi

I recently bought a couple of old brooks saddles and in the box with
them were what I was told were some 1/2inch and 1inch pitch chain
wheels from the 1960s. The thing is I've no idea what they were used
for and I was hoping somebody out there might be able to tell me.
Something to do with sprinting? Single gear perhaps?

1" pitch chains were quite commonly used on track bikes in the Old Days, but
1/2" is now universal, save with a few ruthlessly individualistic
streamliner builders.

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
Among the calamities of war may be jointly numbered the diminution of
the love of truth, by the falsehoods which interest dictates and
credulity encourages.

in message <[email hidden]>, Dave Larrington

(') said:

Also sprach Carl <[email hidden]>:

Quoted message said:

I recently bought a couple of old brooks saddles and in the box with
them were what I was told were some 1/2inch and 1inch pitch chain
wheels from the 1960s. The thing is I've no idea what they were used
for and I was hoping somebody out there might be able to tell me.
Something to do with sprinting? Single gear perhaps?

1" pitch chains were quite commonly used on track bikes in the Old
Days, but 1/2" is now universal, save with a few ruthlessly
individualistic streamliner builders.

If one were a ruthlessly individualistic streamliner builder, what
benefits would one gain (or claim to gain) from using one inch pitch
chains?

--
[email hidden] (Simon Brooke) http://www.jasmine.org.uk/~simon/

;; not so much a refugee from reality, more a bogus
;; asylum seeker

Also sprach Simon Brooke <[email hidden]>:

Quoted message said:

in message <[email hidden]>, Dave Larrington

(') said:

Also sprach Carl <[email hidden]>:

Quoted message said:

I recently bought a couple of old brooks saddles and in the box with
them were what I was told were some 1/2inch and 1inch pitch chain
wheels from the 1960s. The thing is I've no idea what they were
used for and I was hoping somebody out there might be able to tell
me. Something to do with sprinting? Single gear perhaps?

1" pitch chains were quite commonly used on track bikes in the Old
Days, but 1/2" is now universal, save with a few ruthlessly
individualistic streamliner builders.

If one were a ruthlessly individualistic streamliner builder, what
benefits would one gain (or claim to gain) from using one inch pitch
chains?

They don't, they use (IIRC) 8mm industrial chain, thereby permitting
chainrings with enormous tooth counts to be made smaller and lighter.

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
Mushroom! Mushroom!

Dave Larrington said:

They don't, they use (IIRC) 8mm industrial chain, thereby permitting
chainrings with enormous tooth counts to be made smaller and lighter.

Um...you've lost me. Shirley it's not actually the number of teeth
that makes any difference to the gear ratios, etc, but the effective
diameter.

R.

Also sprach Richard
<[email hidden]>:

Quoted message said:

Dave Larrington said:

They don't, they use (IIRC) 8mm industrial chain, thereby permitting
chainrings with enormous tooth counts to be made smaller and lighter.

Um...you've lost me. Shirley it's not actually the number of teeth
that makes any difference to the gear ratios, etc, but the effective
diameter.

A 77-11 (say) is a a seven to one step-up irrespective of the pitch of the
chain, but a 77T conventional chainring has a diameter of 311 mm, whereas an
8mm pitch one would be but 196 mm across.

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
It would appear apparent, to me at least, that dinosaurs were largely
burrowing creatures.

Dave Larrington said:

Also sprach Richard
<[email hidden]>:

Quoted message said:

Dave Larrington said:

They don't, they use (IIRC) 8mm industrial chain, thereby permitting
chainrings with enormous tooth counts to be made smaller and lighter.

Um...you've lost me. Shirley it's not actually the number of teeth
that makes any difference to the gear ratios, etc, but the effective
diameter.

A 77-11 (say) is a a seven to one step-up irrespective of the pitch of the
chain, but a 77T conventional chainring has a diameter of 311 mm, whereas an
8mm pitch one would be but 196 mm across.

But how does that work at the back because the 11 tooth would now be
28mm across and not fit on the hub shirley?

--
Tony

"I did make a mistake once - I thought I'd made a mistake but I hadn't"
Anon

Also sprach Tony Raven <[email hidden]>:

Quoted message said:

Dave Larrington said:

Also sprach Richard
<[email hidden]>:

Quoted message said:

Dave Larrington wrote:

> They don't, they use (IIRC) 8mm industrial chain, thereby
> permitting chainrings with enormous tooth counts to be made
> smaller and lighter.

Um...you've lost me. Shirley it's not actually the number of
teeth that makes any difference to the gear ratios, etc, but the
effective diameter.

A 77-11 (say) is a a seven to one step-up irrespective of the pitch
of the chain, but a 77T conventional chainring has a diameter of 311
mm, whereas an 8mm pitch one would be but 196 mm across.

But how does that work at the back because the 11 tooth would now be
28mm across and not fit on the hub shirley?

If one is going to go to the time and effort to make one's own sprockets,
then making a hub should not pose insuperable problems...

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
Although the hippopotamus hath no sting in its tail, the wise man would
rather be seated upon the back of a bee.

Dave Larrington said:

Also sprach Richard
<[email hidden]>:

Quoted message said:

Dave Larrington said:

They don't, they use (IIRC) 8mm industrial chain, thereby permitting
chainrings with enormous tooth counts to be made smaller and lighter.

Um...you've lost me. Shirley it's not actually the number of teeth
that makes any difference to the gear ratios, etc, but the effective
diameter.

A 77-11 (say) is a a seven to one step-up irrespective of the pitch of the
chain, but a 77T conventional chainring has a diameter of 311 mm, whereas an
8mm pitch one would be but 196 mm across.

Still lost. If you wanted a chainring 196 mm across, with the gearing
and weight that implies, then why not make it with *mumble*50ish*mumble*
teeth and the usual pitch?

R.

Richard said:

Dave Larrington said:

Also sprach Richard
<[email hidden]>:

Quoted message said:

Dave Larrington wrote:

>They don't, they use (IIRC) 8mm industrial chain, thereby permitting
>chainrings with enormous tooth counts to be made smaller and lighter.

Um...you've lost me. Shirley it's not actually the number of teeth
that makes any difference to the gear ratios, etc, but the effective
diameter.

A 77-11 (say) is a a seven to one step-up irrespective of the pitch of the
chain, but a 77T conventional chainring has a diameter of 311 mm, whereas an
8mm pitch one would be but 196 mm across.

Still lost. If you wanted a chainring 196 mm across, with the gearing
and weight that implies, then why not make it with *mumble*50ish*mumble*
teeth and the usual pitch?

R.

because at the other end you would need a tiny 7T cog which is far from
round . It wouldn't last and you'd have terrible driveline vibrations
--
---
Marten Gerritsen

INFOapestaartjeM-GINEERINGpuntNL
www.m-gineering.nl

m-gineering said:

Richard said:

Dave Larrington said:

Also sprach Richard
<[email hidden]>:

>Dave Larrington wrote:
>
>
>
>>They don't, they use (IIRC) 8mm industrial chain, thereby permitting
>>chainrings with enormous tooth counts to be made smaller and lighter.
>
>Um...you've lost me. Shirley it's not actually the number of teeth
>that makes any difference to the gear ratios, etc, but the effective
>diameter.

A 77-11 (say) is a a seven to one step-up irrespective of the pitch of the
chain, but a 77T conventional chainring has a diameter of 311 mm, whereas an
8mm pitch one would be but 196 mm across.

Still lost. If you wanted a chainring 196 mm across, with the gearing
and weight that implies, then why not make it with *mumble*50ish*mumble*
teeth and the usual pitch?

R.

because at the other end you would need a tiny 7T cog which is far from
round . It wouldn't last and you'd have terrible driveline vibrations

Ahhhhh (sounds of mental illumination) got it.
I blame my inability to ride at anything near those gear ranges 8-)
Thanks.

R.

Richard said:

Ahhhhh (sounds of mental illumination) got it.
I blame my inability to ride at anything near those gear ranges 8-)

It would be equally useful in producing a very low gear without making
the rear cogs too large ;-)

Roos