Dwane

I just purchased a used Diamondback Expert 9-speed with a Shimano Tiagra Flight Deck set up. I think I did okay for $200, which included the shoes and helmet. This is my first road bike. I did a tear down on it, cleaned, decreased and polished all of the components and reassembled the bike. The only piece that needed to be replaced was a front derailleur. I went to the LBS and purchased a direct replacement, a Shimano FD-4503. I can't seem to get it to go into the to chainring.

After reading the enclosed instructions, searching this site, watching You-Tube videos, visiting Park Tools Website an Shimano's webiste, I have:

1. Installed the front derailleur, setting the gear teeth hight using the attached pro-set gauge.
2. With the chain on the largest sprocket in the rear, set the clearance on the FD between the chain guard and the chain on the smallest chainring.
3. With the shifter in the lowest chainring setting (tension released by depressing the black shifter lever several times), reattached the shifter cable.
4. Expecting to set the outer limit on the largest chainring, shifted the silver/grey shifter once to get it into the center chainring, and then a second time. Unfortunately, it did not shift into the largest chainring. I have tried to use the upper limit screw but that doesn't help.

Any thoughts?

Dwane

davidad

Make sure you have the Der. for brifters. There is a model for flat bars (mountain bike) and is not compatible. Don't ask me how I know that.

mechBgon

At step 4, with the chain on the middle ring, now increase cable tension until there's minimal clearance between the chain and the inner plate of the FD cage, just shy of grazing. Now try step 5, punching into the big ring. Any better?

Jeff Wills

The flat-bar derailleur would be a FD-R453. The "brifter" model would be a FD-4503. As David said, they're not interchangeable.

If the shifter is not pushing the chain far enough to shift the chain to the large chainring, this is a symptom of the incorrect derailleur.

bradtx

Dwane, The FD4503 is for a road triple, this is the instrunction sheet you may've recieved with the FD: https://techdocs.shimano.com/media/te...9830606982.pdf . Did you R/R the crankset or BB? Did it shift with the old FD? If not, what was the problem?

Brad

Dwane

Thank you all for the responses. I believe I have the correct derailleur. My bike is a road bike, not a mountain bike, so the FD4503 should be correct. i did not R/R the crankset or bottom bracket. The old FD didn't work at all due to the spring being either broken or "sprung". This bike was VERY worn. I will try to figure out how to increase the cable tension as mechBgon suggested. I am very mechanically inclined. Beyond air-conditioning work, I have never paid anyone to work on my home or vehicles. I really should be able to figure this out.

mechBgon

I'd expect your bike to have a cable stop on the downtube that has an adjusting barrel. The cable housing stops there, while the inner cable passes through it. Dial that counterclockwise as viewed from the front of the bike to increase cable tension.

bradtx

Dwane, With the shifter cable attached to the FD can you pull it our far enough to center over the big chain ring by hand (not using shifter or pulling cable)? If not, disconnect the shifter cable and try again. This should help determine where the problem is. I have to emphasize something you likely already checked, make sure the FD shifter is fully released by pulling gently on the cable and operating the small STI lever.

Brad