Front Derailleur for (very) compact crank

[Dave Cramer]

I'm experimenting with wide-range double cranks, and am going to try a
44/30... Any thoughts on which front derailleurs might work best?
Front shifting will be friction, so STI compatibility is not an
issue...

Thanks!

Dave

[Steve Palincsar]

Dave Cramer wrote:
> I'm experimenting with wide-range double cranks, and am going to try a
> 44/30... Any thoughts on which front derailleurs might work best?
> Front shifting will be friction, so STI compatibility is not an
>

There are Shimano MTB front derailleurs made specifically for 44T big rings.

[Reflector Collector]

Hey Dave, what are you going to use for a crankset?

I'm toying with the same idea for gearing on an upcoming touring bike.
My thought is that I might be able to use the larger ring for most
application, and the inner 30 for my bailout gear. Running only 2
rings might help avoid going to something with a wider Q-Factor.

I'd really like to find something with a 5 arm 94mm BCD, 172.5 arm
length. I'm probably going to pony up for a TA Carmina from Peter.

[peter...@gmail.com]

They are typically designed for triples, and for bikes with 26"
wheels. That means that the BB drop is not much, and they can make the
cage extend way back and down. When you then try to use that FD on a
frame with 700c rims, and a lot more BB drop, it can hit the
chainstay.

So you may have to use a road double FD. I'd try a 105 or Ultegra.

There are two frame variables in this. BB drop and seat tube angle.
The shallower the seat tube angle, the higher the FD has to be to keep
from hitting the chainstay.

[fox_dog]

Dave -

RBW sells the IRD front derailleur specifically designated for compact
cranks:
http://www.rivbike.com/webalog/shifters_derailleurs/17121.html

It comes in double or triple compatible sizes. I just installed one on
my Blériot with a Sugino 46-36-26 triple and it dialed in rather
nicely. (Mine was marqued "SOMA")

Regards, th

[Steve Palincsar]

peter...@gmail.com wrote:
>
> On Mar 21, 1:30 pm, Steve Palincsar <palin...@his.com> wrote:
>
>> Dave Cramer wrote:
>>
>>> I'm experimenting with wide-range double cranks, and am going to try a
>>> 44/30... Any thoughts on which front derailleurs might work best?
>>> Front shifting will be friction, so STI compatibility is not an
>>>
>> There are Shimano MTB front derailleurs made specifically for 44T big rings.
>>
>
> They are typically designed for triples, and for bikes with 26"
> wheels. That means that the BB drop is not much, and they can make the
> cage extend way back and down. When you then try to use that FD on a
> frame with 700c rims, and a lot more BB drop, it can hit the
> chainstay.
>

I have 22-32-44 microdrive with a Shimano MTB front mech on two road
bikes: a Bruce Gordon Rock 'n Road Tour and a 1991 Ti Spectrum. Both
have triples. In neither case does the FD hit the chainstay. This
setup is a retrofit on the Spectrum; it originally had a SunTour Compe V
front and a 24/44/48 half-step plus granny triple.

[CS]

I did a wide double using 42/26 rings with an 105 double FD. The big
issue with this
is getting the FD to clear the chainstay and not have too big a gap
between the
derailleur and the ring. Still if a 105 double works for 42/26 it will
definitely work for
44/30.

[and...@fluxnow.com]

I run a 46/32 Suntour XC Pro crank on my Rom (two-ring triple crank on
a 103mm BB). I use an XC-Pro MD front derailleur and it works
perfectly after I fiddled with it for a bit (needs to be angled ever
so slightly). It hits the chainstay, but well after it clears the
inner ring. I shift it with Simplex Retrofriction levers.

Before this, I ran a 48/32 TA Cyclotouriste (sadly departed) with a
Superbe Pro front derailleur and the same shifters. That was a great
setup in every respect except for the availability of rings.

AK

[John Speare]

> >
> >> Dave Cramer wrote:
> >>
> >>> I'm experimenting with wide-range double cranks, and am going to try a
> >>> 44/30... Any thoughts on which front derailleurs might work best?
> >>> Front shifting will be friction, so STI compatibility is not an
> >>>

I just put this setup on a bike. The bummer with this approach using
what's easily available today is that you have to use 110/74, which
forces you to set up the 74 to get the 30t ring -- and therefore
messes up your q factor and more importanly, pushes the 44 out too far
to make it usable with the full range of gears in the rear.

check out alex's remarks on this setup:
http://blogs.phred.org/blogs/alex_wetmore/archive/2006/01/22/95.aspx

I found some slightly used ritchie 94/58 cranks and got a perfect
setup with a 103mm bottom bracket. I'm running 12-34 on a 9 speed
cassette and I have reasonable chain line up to the 32 t cog.

to finally come around and answer your question: I'm using a mid-90's
(pretty sure it came off a 93 bike) XT front derailleur. shifts fine,
though i did have to fuss with it more than normal to get the angle
just right.

--
John Speare
Spokane, WA USA
http://cyclingspokane.blogspot.com/
Burley tandem for sale: http://www.johndogfood.com/john/burleysale.html

[jpvaliensi]

Hullo All,
I use the 44-30 ring combo. I have had good success with regular road
derailleurs. One set up I have uses Shimano flat-bar controls with the
matching front mech. These parts are for road bikes with flat bars. My
front derailleur is wat to high, because the frame is set up for braze
on derailleurs, but no matter it shifts just fine. On this bike I used
a Deore crank with a chain gaurd in the outer spot, a 44 in the middle
spot, and a 30 in the granny location. These rings were a special
order from PJW.
Cheers!

[Leonard Bulger]

Hi Everybody,

Does anyone know if the IRD front derailleur will work with a TA
cyclotourist crank? The TA has less room between the crank arm and
the large ring than modern cranks. A lot of derailleurs have too wide
a cage and won't work. I've ordered CT' repro Stronglight
Supertourist rings in 44 and 26 teeth to go un the TA. I was thinking
of using a Simplex, Nuovo Record or 980 derailleur.

Leonard

On Mar 21, 1:57 pm, "fox_dog" <hubbard....@gmail.com> wrote:
> Dave -
>
> RBW sells the IRD front derailleur specifically designated for compact
> cranks:http://www.rivbike.com/webalog/shifters_derailleurs/17121.html
>

.>
> > Dave

[Keith Ayres]

My Flying Gate was built up with a NOS braze-on type FD (with the
vertical seat tube, a specific bracket for braze-ons is needed). It is
totally devoid of brand names, but I seem to recall it was a Mafac (?
did they ever make gears as well as brakes?) that the builder had in
his parts bin.
It is ideal for 40/26, clears the chainstay, not too far away from the
large ring.

[littlecircles :: mike beganyi]

Hi Dave,

I'm running a TA Carmina double 94 bcd so I can use a wide range of
rings.
I've successfully used a Campy Chorus FD double compact to index shift
(Record Ergos) the following: 34/50, 34/48. adn 32/48.
I may run 32/44 or 30/44 for a stretch this summer. and I do not
foresee any issues - but I do have a backup Shimano compact double FD
that worked well with some other odd combinations that I can fall back
on.

I'm exploring moving to friction bar end for the FD. I have the
occasional random miscue and feel I can eliminate it with friction.
(and I rarely need to shift the FD while standing)

-Mike