What is 1/2 inch pitch?

[Carl]

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?

Thanks in advance


Carl

 

[Dave Larrington]

Also sprach Carl <[email protected]>:
> 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.

 

[Simon Brooke]

in message <[email protected]>, Dave Larrington
('[email protected]') wrote:

> Also sprach Carl <[email protected]>:
>> 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 protected] (Simon Brooke) http://www.jasmine.org.uk/~simon/

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

 

[Dave Larrington]

Also sprach Simon Brooke <[email protected]>:
> in message <[email protected]>, Dave Larrington
> ('[email protected]') wrote:
>
>> Also sprach Carl <[email protected]>:
>>> 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!

 

[Richard]

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.

R.

 

[Dave Larrington]

Also sprach Richard
<[email protected]>:
> 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.

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

 

[Tony Raven]

Dave Larrington wrote:
> Also sprach Richard
> <[email protected]>:
>
>>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?

--
Tony

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

 

[Dave Larrington]

Also sprach Tony Raven <[email protected]>:
> Dave Larrington wrote:
>> Also sprach Richard
>> <[email protected]>:
>>
>>> 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.

 

[Richard]

Dave Larrington wrote:
> Also sprach Richard
> <[email protected]>:
>
>>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.

 

[m-gineering]

Richard wrote:
>
> Dave Larrington wrote:
> > Also sprach Richard
> > <[email protected]>:
> >
> >>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

 

[Richard]

m-gineering wrote:
> Richard wrote:
>
>>Dave Larrington wrote:
>>
>>>Also sprach Richard
>>><[email protected]>:
>>>
>>>
>>>>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
Thanks.

R.

 

[Roos Eisma]

Richard <[email protected]> writes:

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

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

Roos