john
i might go for a smaller chain ring... cheaper then a single speed freewheel.... (if thats what you have? or is it a cassette / freehub ?) I think the crank you have has a 110 bcd ?? these chainrings are a dime a dozen used.. (who doesn't have a 36 or 38 mtb chainring ?, or rocket chainrings are inexpensive... )
Although there are certain advantages to a running bigger cogs and bigger chainrings, (these being less force in the chain and more chain and teeth = better durability), the disadvantages are the eccentricity and trueness are exaggerated so its harder keep the chain properly adjusted and throwing a chain is more likely as well.
Tony Pereira wrote: Check out this gear calculator:
http://www.sheldonbrown.com/gears/
Shoot for about a 57" gear. With a 48T chainring and 700x32 tires you
would want a 22.
-Tony
Leibowitz, Flo wrote:
> Very informative. Can I ask a similar question? The only bike I can
> use for cross is a 48-16 Bianchi San Jose. Commuter bike by any other
> name, I guess. It wasn't horrible at Kruger's, but that was mostly dry
> and a lot of it was flat or downhill. If I were to change the rear cog
> only (cheap and easy), what might I change it to that could be helpful?
>
> ------------------------------------------------------------------------
> *From:* obra-bounces@list.obra.org on behalf of Tony Pereira
> *Sent:* Sun 9/23/2007 9:38 AM
> *To:* Matthew Klahn
> *Cc:* obra@list.obra.org; Will Cortez
> *Subject:* Re: [OBRA Chat] Any suggestions for SS 'cross gearing?
>
> 2:1 is good for 26" mtb singlespeeding. For SS cross most of us run
> somewhere around 39/19/18/17. I've heard of a few guys going as small as
> a 39/15--you gotta have some legs for that.
>
> You might get more response to this on a non-race day!
>
> -Tony
>
> Pereira Cycles
> Portland, Oregon, USA
> www.pereiracycles.com
> 503.333.5043
>
>
>
> Matthew Klahn wrote:
> > When I was researching this same topic, I found this page:
> >
> > http://sheldonbrown.com/singlecross.html
> >
> > Which recommends something close to a 2:1 gain ratio (34/17, 36/18,
> > etc.) unless you're superhumanly strong. However, I've never raced
> > 'cross yet, let alone single-speed, so hopefully someone more
> > knowledgeable will reply, too...
> >
> > Matthew
> >
> > On 9/22/07, Will Cortez wrote:
> >
> >> I was thinking about making my life harder by riding 'cross SS. Any
> suggestions out there for gearing? What would be a catch-all ratio
> that will keep me competitive...assuming I'm willing to hoof it on
> really tough sections :)
> >>
> >> -will
> >> _______________________________________________
> >> OBRA mailing list
> >> obra@list.obra.org
> >> http://list.obra.org/mailman/listinfo/obra
> >> Unsubscribe: obra-unsubscribe@list.obra.org
> >>
> >>
> > _______________________________________________
> > OBRA mailing list
> > obra@list.obra.org
> > http://list.obra.org/mailman/listinfo/obra
> > Unsubscribe: obra-unsubscribe@list.obra.org
> >
> >
> _______________________________________________
> OBRA mailing list
> obra@list.obra.org
> http://list.obra.org/mailman/listinfo/obra
> Unsubscribe: obra-unsubscribe@list.obra.org
>
> ------------------------------------------------------------------------
>
> _______________________________________________
> OBRA mailing list
> obra@list.obra.org
> http://list.obra.org/mailman/listinfo/obra
> Unsubscribe: obra-unsubscribe@list.obra.org
>
_______________________________________________
OBRA mailing list
obra@list.obra.org
http://list.obra.org/mailman/listinfo/obra
Unsubscribe: obra-unsubscribe@list.obra.org
john m schmidt, pe
portland oregon