"Matt O'Toole" <
[email protected]> wrote in message
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>
> "Bluto" <
[email protected]> wrote in message
>
news:[email protected]...
>
> > "Wayne T" <
[email protected]> wrote:
> >
> > > I am looking for a good crankset for my and my wife's
> touring bikes. At
> > > first I was looking at TA Zephr because it gives the
> greatest flexibility of
> > > gear sizes but is quite expensive. Also, I was told
> that the Dura Ace low
> > > is only a 24. I want a 22.
> >
> > For versatility in chainring sizes, you want 110mm BCD
> rings for the
> > middle and outer positions. Usually this means a 110/74
> cranks, which
> > means a minimum 24t small ring. That's what I would
> strongly
> > recommend unless there's some reason you _must_ use a
> granny ring
> > smaller than 24t.
> >
> > The TA Zephyr is the only crank I know that has 110mm and
> 56/58mm BCD
> > patterns together on the same arm. Plenty of MTB cranks
> use 94/58
> > BCDs, but using one of those will put a serious limit on
> what ring
> > sizes you can get. Likewise any 4-arm crank, like the
> Shimano XT unit
> > you mention.
>
> Another possible solution is a110/74 crank with an Avid Microdapter, which converts the inner bolt
> circle to 58 or 56, so you can use a 22T inner ring. They're probably not made anymore, but a
> resourceful person should be able to find one.
>
> However, using such a small inner ring with normal road-sized outer would probably exceed the
> limits of your derailers. I've used a 22T inner with a 46T outer on a mountain bike with no
> problems, but I think that's about the limit -- and that was with old Deore DX gear, which was
> particularly flexible. Newer stuff doesn't do as well with unconventional setups.
>
> > What are you going to get by using a 22t ring that you
> would not by
> > using a 24t and a step larger in the rear cluster?
>
> That *is* a good question...
>
> > > However, I just found a 22/33/44T Shimano Deore XT Crankset for $140 weighing in at 647g. or
> > > 1.4 lbs.
> Since TA is a lot more
> > > expensive, what exactly am I getting for this much
> higher price? Is it much
> > > stiffer as well as lighter?
> >
> > Rivendell on TA Zephyr: "It weighs about 700g with rings
> (175 mm)."
> >
> > With cranks, lighter almost always means less stiff. The
> difference
> > in stiffness between different lightweight aluminum cranks
> is
> > negligible, whichever you choose. If most riders
> preferred stiffness
> > at the cranks, they would never have accepted sealed
> cartridge BBs,
> > which rob much more stiffness than barely-hollowtech
> cranks could ever
> > restore.
>
> I don't think stiffness is an issue at all, unless you're really big. Even then, just because you
> can feel it doesn't mean it matters. Besides, it's probably the frame and BB axle you feel
> flexing, not the crank. The problem with aluminum cranks is that if you're big and strong and can
> feel them flexing, you might be at risk of breaking them. Aluminum doesn't like to be flexed.
>
> If you've ever seen a cross section of a Hollowtech crank, you'd think it was a joke. The hollow
> part is about as big as a grain of rice. I'm sure it doesn't help anything, but it probably
> doesn't hurt either, except make the cranks more expensive to make. But that's Shimano's problem,
> not yours, because an XT crank would be priced at $150 whether it were Hollowtech or diamond
> studded pewter.
>
> That said, the new XT crank might be fine -- but a 110/74 crank will still give you the best
> selection of chainrings. I'd be more inclined to use an older Shimano XT/DX/RSX, Suntour XC Pro,
> or Ritchey crank with said bolt circle, and maybe the Microdaptor if you really want that 22. You
> should be able to find one of these cranks pretty cheap, and it might even work with your old BB.
>
> The TA is neato, but spending over $200 on a crank is completely insane, at least to me. That's
> well off the value chart, where bikes start having more in common with things like Rolex watches
> and Bentleys.
Yeah, I'm with you. If I am happy with a 22/32/44 set up on an XT, would this work on my road bike,
or is there a problem with using a MTN Bike crank set on a road bike? BTW, I take it that a Campy
racing triple does not have a 22 granny gear.
>
> Matt O.
>
>