26-42 double?

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

You might try a 110/74 triple crank, and just use the inner two positions.
It may not quite get the q-factor down where you want, but it might. TA
cyclotouriste cranks would also work, but may be harder to locate.

I use a 46/30 myself, using mountain bike cranks with the granny left off.
But that is as low as you can go on the inner ring that way.

--

David L. Johnson

__o | Accept risk. Accept responsibility. Put a lawyer out of
_`\(,_ | business.
(_)/ (_) |

In article <[email hidden]>, Art

() said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

If you are lucky, you may be able to lay hands on a Stronglight 49D or
TA Cyclotouriste which can be set up thusly.

--
Dave Larrington - <http://www.legslarry.beerdrinkers.co.uk/>
Dead journalists make excellent objets d'art.

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there an y way, other than
a custom crank to get what I want?

TA Cyclotouriste was discontinued only recently (within the past
year?), there should be plenty around, and the Q-factor will be the
lowest available (13xmm?). T

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Art

Due to Campagnolo only making a few bottom brackets, and having
assymetrical and symetrical versions, I doubt you can get your current
Mirage crankset to work. But you can just use a triple crankset on a
double length bottom bracket. Use single ring crankarm bolts to hold
the middle ring in place and take off the outer ring. Using a small 26
or 24 tooth inner ring should make it easily clear the chainstays.
Only time rings hit the chainstays is if you use a large inner ring.
Best/only crank to use would be one taking a Shimano JIS square taper
bottom bracket. Then you can get very short square taper bottom
brackets to bring the crank in as close as possible.

Quoted message said:

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Art

Due to Campagnolo only making a few bottom brackets, and having
assymetrical and symetrical versions, I doubt you can get your current
Mirage crankset to work. But you can just use a triple crankset on a
double length bottom bracket. Use single ring crankarm bolts to hold
the middle ring in place and take off the outer ring. Using a small 26
or 24 tooth inner ring should make it easily clear the chainstays.
Only time rings hit the chainstays is if you use a large inner ring.
Best/only crank to use would be one taking a Shimano JIS square taper
bottom bracket. Then you can get very short square taper bottom
brackets to bring the crank in as close as possible.

A *possible* complication with this is whether the front derailleur has
enough inboard travel to shift to the inner chainring. The only way to
find out is to put the bike together and try it.

Sheldon Brown's Hetchins is set up kind of like this, except it's a
50/28:
http://www.sheldonbrown.org/hetchins/source/3.html

Jeff

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Art

Use a TA Carmina crank http://www.peterwhitecycles.com/carmina.asp

CC

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

The TA Cyclotouriste crank can do that. I currently have 27-43 on one of
my bikes.

--

John ([email hidden])

Quoted message said:

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Quoted message said:

Due to Campagnolo only making a few bottom brackets, and having
assymetrical and symetrical versions, I doubt you can get your current
Mirage crankset to work. But you can just use a triple crankset on a
double length bottom bracket. Use single ring crankarm bolts to hold
the middle ring in place and take off the outer ring. Using a small 26
or 24 tooth inner ring should make it easily clear the chainstays.
Only time rings hit the chainstays is if you use a large inner ring.
Best/only crank to use would be one taking a Shimano JIS square taper
bottom bracket. Then you can get very short square taper bottom
brackets to bring the crank in as close as possible.

there's no reason he couldn't do that with a 26 and 42 on
his present Mirage crank and a slightly shorter spindle. As
you point out a smaller ring can sit much closer.

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

JeffWills said:

Quoted message said:

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Art

Due to Campagnolo only making a few bottom brackets, and having
assymetrical and symetrical versions, I doubt you can get your current
Mirage crankset to work. But you can just use a triple crankset on a
double length bottom bracket. Use single ring crankarm bolts to hold
the middle ring in place and take off the outer ring. Using a small 26
or 24 tooth inner ring should make it easily clear the chainstays.
Only time rings hit the chainstays is if you use a large inner ring.
Best/only crank to use would be one taking a Shimano JIS square taper
bottom bracket. Then you can get very short square taper bottom
brackets to bring the crank in as close as possible.

A *possible* complication with this is whether the front derailleur has
enough inboard travel to shift to the inner chainring. The only way to
find out is to put the bike together and try it.

True. I sort of had this problem putting a shorter bottom bracket on a
triple of mine. The Sora double front derailleur barely, barely goes
in far enough to drop to the inner ring. This inward travel was the
deciding factor on which length of bottom bracket I ended up with.
Taking a file to the back side of the Sora derailleur helped get an
extra millimeter or two of inward travel.

Quoted message said:

Sheldon Brown's Hetchins is set up kind of like this, except it's a
50/28:
http://www.sheldonbrown.org/hetchins/source/3.html

Jeff

A Muzi said:

Quoted message said:

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Quoted message said:

Due to Campagnolo only making a few bottom brackets, and having
assymetrical and symetrical versions, I doubt you can get your current
Mirage crankset to work. But you can just use a triple crankset on a
double length bottom bracket. Use single ring crankarm bolts to hold
the middle ring in place and take off the outer ring. Using a small 26
or 24 tooth inner ring should make it easily clear the chainstays.
Only time rings hit the chainstays is if you use a large inner ring.
Best/only crank to use would be one taking a Shimano JIS square taper
bottom bracket. Then you can get very short square taper bottom
brackets to bring the crank in as close as possible.

there's no reason he couldn't do that with a 26 and 42 on
his present Mirage crank and a slightly shorter spindle.

The problem is with the Campagnolo crank. Assuming he already is using
the shortest 111mm spindle, AC-H or AC-S, etc. Expensive Phil Wood
bottom brackets are the only shorter spindles I know of. And if you
are using a Mirage crankset, a Phil bottom bracket that costs twice the
price of the Mirage crank probably isn't what you want. The
Mirage/Veloce/Centaur takes a symmetrical spindle and the ISO
Campagnolo taper. So the 102mm assymetrical Chorus/Record bottom
bracket will not work due to the symmetry problem. And shorter JIS
taper bottom brackets have the wrong taper. Some love to intermix
bottom brackets and cranksets with different tapers. Not for me but
others can try it.

As

Quoted message said:

you point out a smaller ring can sit much closer.

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

Art said:

I run a 26-40-50 Campy Mirage triple. I want to
try a crank with a lower q-factor, due to knee
problems, and I hardly ever use the 50. So I would
want a 26-42 double. The compact doubles I have
seen don't go that low. Is there any way, other than
a custom crank to get what I want?

Art

Yeah, just use a triple chainset and ignore the outer ring, or (better)
remove it and use single chainring bolts to hold the middle ring.

I run 26-42-52 on my touring bike and it shifts OK.

Quoted message said:

True. I sort of had this problem putting a shorter bottom bracket on a
triple of mine. The Sora double front derailleur barely, barely goes
in far enough to drop to the inner ring. This inward travel was the
deciding factor on which length of bottom bracket I ended up with.
Taking a file to the back side of the Sora derailleur helped get an
extra millimeter or two of inward travel.

A 1.5-2 mm freewheel spacer put on prior to installing the right side
of bb works too.