compact cranks & fr. der

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?
-----------------
Alex

Maybe you can keep it, but it depends.
If you are switching from a road triple, probably.
If you are switching from a double ring, probably not.

What are you switching from?
double or triple?
what brand?
what ring sizes?

What are you switching to?
what brand?
what ring sizes?

What brand/model derailieur do you have?

hth,

bookieb.

Quoted message said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?

I'm using an ordinary 9sp 105 front der on a Nashbar compact crank
50/34, and it works perfectly. Haven't ever tried the compact-specific
front ders because this one is fine.

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?

So far, I've been able to keep the original der and just reposition it
on the seat tube when making this swap, but IMO the real answer is
"try it and see".
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Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?
-----------------
Alex

I use a Campagnolo Veloce double 10 speed, not the compact specific
one, front derailleur to shift a micro compact crankset. 48-30 rings
on a 94mm bcd crank. I took the plastic thing out of the Campagnolo 10
speed front derailleur. It shifts OK. But you do have to move it
around and twist it to get it into the perfect spot, and monkey with
the limit screws. The bends and kinks and bulges in the cages of the
front derailleur do not hit the chain at the perfect spots to move it
between rings if you have the front derailleur adjusted for a normal
gap between rings. So you have to twist the front derailleur around
and play with the limit screws.

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?
-----------------
Alex

I switched from a Shimano 53/39 crank to a 46/34 and kept my standard
105 two ring derailleur. I did have to lower it on the seat tube, but
it has worked perfectly for me.

Smokey

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?
-----------------
Alex

Use the one you have, even if it's a triple FD...no need for ther
'compact' ones.

bookieb said:

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?
-----------------
Alex

Maybe you can keep it, but it depends.
If you are switching from a road triple, probably.
If you are switching from a double ring, probably not.

Not true...I have been installing compacts using standard road double
FDs from the beginning...NO need for a new FD..

Quoted message said:

What are you switching from?
double or triple?
what brand?
what ring sizes?

What are you switching to?
what brand?
what ring sizes?

What brand/model derailieur do you have?

hth,

bookieb.

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?

As has been posted, you don't "need" a new one; the standard double
will work. The question is how well it will work, since it there are
two differences between the compact and standard rings: the
circumference and the 16 tooth jump shifting up from 34 to 50 (as
opposed to 14 from 39 to 53). The compact specific derailleurs are
designed with a smaller circumference and to gap the bigger jump.

I have been running compact for 3 years now with Shimano compatible
components, and have tried a lot of combinations in that time,
including:

Ultegra shifter, Ultegra standard front;
Dura Ace shifter, Dura Ace standard front;
Ultegra shifter, FSA C-16 compact front;
Dura Ace shifter, FSA C-16 compact front.

IME, the last combo has by far faster, crisper up-shifting than any of
the others, followed by Dura Ace/Dura Ace and Ultegra/FSA. There is
distinct hesitation no matter how much futzing and adjusting with
cable tension, limits, and derailleur height with all of the combos
except the last.

As far as downshifting, I found that the 16 tooth distance in many
gear combos resulted in the chain being thrown off the small ring into
the frame, so I attached a dog fang chain watcher.

The cheapest and easiest solution for you obviously is to try out your
current set up and see how it works, and tweak as necessary.

In any case, you will need to lower the derailleur height on the seat
tube, and take 2 links out of your chain.

I've had similar results to Doug. You can make a reg front derail work.
The compaq front seems to work better. I used a Campy Centaur compact front
as I'm a Campy bigot and it was abt half of a chrous or record.

"Doug Taylor" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Alex said:

If I switch out to compact cranks, can I keep my standard derailleur or
would I need to get a new one?

As has been posted, you don't "need" a new one; the standard double
will work. The question is how well it will work, since it there are
two differences between the compact and standard rings: the
circumference and the 16 tooth jump shifting up from 34 to 50 (as
opposed to 14 from 39 to 53). The compact specific derailleurs are
designed with a smaller circumference and to gap the bigger jump.

I have been running compact for 3 years now with Shimano compatible
components, and have tried a lot of combinations in that time,
including:

Ultegra shifter, Ultegra standard front;
Dura Ace shifter, Dura Ace standard front;
Ultegra shifter, FSA C-16 compact front;
Dura Ace shifter, FSA C-16 compact front.

IME, the last combo has by far faster, crisper up-shifting than any of
the others, followed by Dura Ace/Dura Ace and Ultegra/FSA. There is
distinct hesitation no matter how much futzing and adjusting with
cable tension, limits, and derailleur height with all of the combos
except the last.

As far as downshifting, I found that the 16 tooth distance in many
gear combos resulted in the chain being thrown off the small ring into
the frame, so I attached a dog fang chain watcher.

The cheapest and easiest solution for you obviously is to try out your
current set up and see how it works, and tweak as necessary.

In any case, you will need to lower the derailleur height on the seat
tube, and take 2 links out of your chain.