Hi Dan... One thing to check for is that the derailleur is "clocked" correctly on the seat tube... If the derailleur is rotated tword the back of the bike the cage will not have enough chearance... You should be able to change at least 3 in the rear with out needing to "clean up" the front...
Don Williams Woodinville Washington USA
On Sat, May 3, 2008 at 10:48 AM, David Snyder <dddd@pacbell.net> wrote:
> Dan,
>
> On my bikes it's ALL 5, 6 or 7 cogs with the big ring, but I never use the
> smallest cogs with the small ring.
>
> Sometimes (usually) I'll spread the cage a tiny amount in order to clear top
> gear. It helps greatly (is necessary) to have a true-running big ring.
>
> The spreading technique I use is to put the jaws of a duckbill plier (short,
> flat jaws, long handles) between the cage plates, up near the cage's bridge,
> then pull the handles apart.
> The plier's handles will usually fall between spokes as positioned.
> All of the bending, a mm or two(?), occurs in the thinner outer plate,
> allowing for top-gear clearance with the chain.
>
> Note that modern chains noticeably increase clearance with both inner and
> outer cage plates and also make shifting at the rear more forgiving, so I
> almost always use these now, but I've easily gotten 5 or 6 cogs worth of
> cage clearance using original chains as well.
>
> I advise care so as to not over-spread the cage. Best to measure first so
> as to guage progress in bending. Also, best try to concentrate force toward
> the top edge of the outer cage plate, so as to keep the lower edge of the
> cage plate from flaring out excessively.
>
> I've done this to more than a few front NR derailers, and am not tossing any
> chains while riding hard here in the rolling-hilly(duh!) foothills.
>
> One should, however, probably keep the cage's foreward tab bent (subtly)
> inward to the degree allowed by the chain's running clearance, noting that
> the chainring flexes outward a good 1-2mm as the right crankarm is pushed
> down around 3-o'clock.
>
> Best of luck,
>
> David Snyder
> Auburn, CA usa
>
>
>
>
> > I have a question about how good of an adjustment one
> > can get with a NR front derailleur/crank with a 5
> > speed rear cluster.
> >
> > The question is, from your experience, how many rear
> > cogs can you hit without having to adjust the front
> > derailleur to prevent rub?
> >
> > On my other bikes (simplex mostly), I can shift over
> > 3-4 cogs without having to fine tune the front to
> > prevent rub. And I find the larger chainwheel is more
> > sensitive.
> >
> > On my Raleigh International, I seem to not be able to
> > move 1 cog without having to adjust the front
> > derailleur, again, especially when on the larger
> > chainwheel.
> >
> > So before I go and work on it, I thought I would find
> > out from y'all what to expect. Thanks in advance.
> >
> > Dan Kasha
> > Seattle Wa, USA where we are still skiing on a 15 foot
> > base of snow, but have glorious cycling weather (with
> > some showers).