On Dec 17, 6:30 pm, "David L. Johnson" <[email hidden]>
Quoted message said:Quoted message said:Mark Pryor said:hello,
Quoted message said:Quoted message said:Is it realistic to have 2 sets of wheels with mounted cassettes and expect
that derailleur settings are cross compatible?
Quoted message said:Quoted message said:I have a 9 speed shimano/tiagra bike with Richey Aero wheels (24/28). The
cassette is 12-25.
Quoted message said:Quoted message said:I'm ready to put together a Mavic SL wheelset (18/20) and Dura-ace cs-7700
(12-23/9 speed)) cassette, with new tubes and Vredstein tires.
Quoted message said:Quoted message said:The bike has no chain disc.
What on earth is a chain disc?
Quoted message said:The rear Mavic hub came with an extra shim
Quoted message said:for the cassette. My first attempt will be without this shim. If it
tightens properly, will I be OK without it?
Try it and find out. I would hope that all Shimano-compatible hubs have
the same cassette positioning, but maybe not. It's easy enough to fix
with a shim, though, since ease of swapping wheels is the goal, right?
I do this all the time; I have a "flatland" wheel and a hilly-ride
wheel. But both are Campy hubs (that is, both are the same brand), and
so there is no problem with swapping them.
Quoted message said:Quoted message said:My goal is for the derailleur settings to be the same for both so that
both wheelsets are interchangeable.
Sure.
Quoted message said:The "brake tracks" on the rims need to be as close to identical as
possible. No brake pads into tire sidewalls, IOW.
Nonsense. The position of he braking flats on the wheel is determined
by the size --- all 700c's have the braking flats in exactly the same
position, just a couple mm short of the top of the rim, which is uniform
within less than 1 mm because they all have to take the same tires. No
way that a brake adjusted properly for one rim will be into the tire
sidewall of another. Cannot happen.
Also, no large
Quoted message said:difference in sidewall "slant" from vertical (perhaps not as common as
in previous eras), so you don't wind up with worn pads ("beveled"😉
that only work with one set of rims, and/or grab on the other,
especially when attempting a fast stop. Make that a *safe* (and still
seated) fast stop.
Again, not an issue. What might be an issue is the width of the rim,
which can vary. You can usually adjust for this with the brake barrel
adjuster, unless you have wildly different rims.
I didn't think about rim width (confession), not having used anything
wider than 20mm or so in a good long while (although there was still a
pair of 27" x 1-1/4" touring wheels in the fleet up 'till '99 or so).
I had a table of widths around here somewhere-- what commonly used
road rims, especially on factory-builts, are wide or narrow enough to
matter?
(Onward) I'm not familiar with any of the factory built wheels
currently available (more of a smile than a confession). Who knows (he
asked) with the wildly different marketing ooops technological
advances in design exhibited among the various popular choices, where
rim (brake track) layout has gone?
The "caution" does concern experience with (mostly) older rims. I
could list those I've used: Nisi Mixer, Campy Moskva (still in the
wrappers <g>, too different!), Sun Mistral, various box-section sewup
and clincher rims from Ambrosio, Super Champion, Campagnolo, Fiamme,
Wolber, Mavic. WIth the Mavics, whatever rim I had in there previously
(probably Wolber Alpine, could have been Campy), the brake pad rode a
little low for those Open 4CD's. Maybe my first adjustment wasn't
optimal? Add that to the mix.
So, yeah, "different enough", and there are several other "old" rims I
didn't use that would apply.
The caution also concerns heavily worn brake pads that gave problems
when switching to a rim they were not worn in on. Did I say that
earlier? That's where I seem to remember having real difficulties.
Adding, on a little reflection, one reason to get rims that are
compatible when switching is, you won't "blow" an adjustment to brake
pad alignment, especially (my favorite scenario) when you're already
late for the ride and find that tire that slow-leaked flat on you from
the day before.
Further adding, another advantage of using handbuilt wheels is, you
can use "all the same" rims on all your wheels, or at least on the
daily drivers. Personally, that goal is becoming reality.
--D-y