headtube reducer

ellis wrote:
> I'm looking to get one of these
> http://store.airbomb.com/ItemDesc.asp?IC=HD7200 to install an 1" mtb fork on
> a 1 1/8" mtb headtube. It says it's "for converting a BMX 1 1/8" headtube
> to a 1" headtube." Is there a difference in size between a mtb 1 1/8"
> headtube and a bmx 1 1/8" headtube? Will this work? TIA
>
>
>
it'll work, but why? sell the 1" for to a retrogrouch that wants it
[and will overpay] and use the money to buy a fork that fits properly.
seriously, people pay crazy $'s for beaten up, used 1" mtb forks because
they have 1" frames that they want to keep using.

ellis wrote:
> I'm looking to get one of these
> http://store.airbomb.com/ItemDesc.asp?IC=HD7200 to install an 1" mtb fork on
> a 1 1/8" mtb headtube. It says it's "for converting a BMX 1 1/8" headtube
> to a 1" headtube." Is there a difference in size between a mtb 1 1/8"
> headtube and a bmx 1 1/8" headtube? Will this work? TIA

BMX headsets for one inch systems have a 34mm head tube
bore, same as road and offroad headsets for 1-18 inch systems.

To use a road or offroad one inch headset with a 30.2 (ISO)
or 30.0 (JIS) bore in a 34mm frame, a simple aluminum
sleeve, as you found, is all that's needed.

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

A Muzi wrote:
> ellis wrote:
> > I'm looking to get one of these
> > http://store.airbomb.com/ItemDesc.asp?IC=HD7200 to install an 1" mtb fork on
> > a 1 1/8" mtb headtube. It says it's "for converting a BMX 1 1/8" headtube
> > to a 1" headtube." Is there a difference in size between a mtb 1 1/8"
> > headtube and a bmx 1 1/8" headtube? Will this work? TIA
>
> BMX headsets for one inch systems have a 34mm head tube
> bore, same as road and offroad headsets for 1-18 inch systems.
>
> To use a road or offroad one inch headset with a 30.2 (ISO)
> or 30.0 (JIS) bore in a 34mm frame, a simple aluminum
> sleeve, as you found, is all that's needed.
>

Ummm... Sheldon says the BMX 1" headset fit in a 32.7mm bore:
http://www.sheldonbrown.com/handsup.html#sizes ,
so the answer to the Ellis's question is "no". The correct adapter is
this:
http://harriscyclery.net/site/page.cfm?PageID=49&SKU=HD9901

Jeff