Hendo252 

I've put flat bars and rapidfire trigger shifters on my old 7-speed Trek 620 road bike. All works great except the FD, which over shifts with the MTB shifters.

So... I was hoping to get a recommendation on a FD that will work with the shifters and the existing gearing; see below for the specifics.

I've looked through the specs on many MTB FD's but my gearing exceeds one or more specs on all of them, and I'm not sure where to fudge. So if somebody has been down this road and found a good solution, I hope you will share your experience.

Any thoughts appreciated!

-H

Here are the specifics:
Trek 620 set up for 28.6mm clamp-on FD
7-speed 12-28 rear cassette
Sugino AT triple crank 28-40-50
Shimano EF-65 shifters & cables

fietsbob

Friction shifting is the great equalizer ... lose the front Rapid fire, instead fit a Thumb shift lever..

HillRider

Shimano does make flat-bar shifters that work with road front derailleurs but that means buying another shifter. Fietsbob is correct that friction shifting is completely agnostic and will shift nearly any front derailleur over nearly any crank. If you aren't wedded to index front shifting, a friction shifter will certainly solve your problem.

Hendo252 

Thanks for the quick responses.

i'd prefer to just swap the FD if possible... Hoping for some suggestions.

If I can't find a compatible FD I'll look again at friction.

Bill Kapaun

Just get a mountain FDER designed for 28-38-48.

HillRider

Are there any?

Bill Kapaun

Yes.

HillRider

What make and model?

Bill Kapaun

What's your point?

Shimano makes a bunch of them as found on your plain vanilla 8 speed hybrid triples.
FC-M151, FC-M410/11, C0-50/51 etc.

Hendo252 

Hmmm... I never thought about seeing what the hybrid bikes are equipped with.

maybe the FD-M311?
Universal Cycles -- Shimano FD-M311 Altus Front Derailleur

both are 7-speed compatible.

my application exceeds the max chainring (50 vs 48) and capacity (20 vs 22) by two teeth each.... Hopefully close enough.

the outer/middle difference fits (10t for both).

i have a larger inner ring (28 vs 20) so i think that will work?

thoughts?

Thanks!

Jeff Wills

The derailleur you want is the Shimano FD-R453. If your local shop doesn't have one, try Harris Cyclery: Shimano, IRD Front Derailleurs (Derailleurs) from Harris Cyclery

I have its predecessor, the FD-R443, on a couple bikes with 24/42/52 chainrings and "mountain" or "flat-bar" shifters. It works perfectly, and has for nearly a decade. Take a look:
All My Bikes
All My Bikes

The difference between the FD-R443 and the FD-R453 is that the later version has a deeper inner plate to better match up with a 39-tooth middle chainring. With your 28/40/50 setup, the FD-R443 is probably the better choice if you can find one.

Hendo252 

Thanks Jeff - great info and exactly what I was hoping for. Harris shows the 443 as unavailable but I found a NOS unit elsewhere and it is on its way.

the Beer (or beverage of choice is on me if we ever meet face-to-face.

-Tom in SoCal

Jeff Wills

Dude... I grew up in SoCal (Pasadena area) and I'll be visiting around Christmas. However, I now live in the Land of Beer : Portland. I'm friends with Jamie Emmerson, the brewmaster for Full Sail Brewing. Jamie donates beer to the recumbent races I go to every year.