Hi,

I'm wanting to fix up my girlfriend's rusty hybrid bike but I'm having trouble identifying what kind of front derailleur I need.

As you can see in this pic, the frame has little grooves for the clamp to fit in. Are clamps a standard size that will all fit in this? The seat tube of the frame measures 3cm wide.



The bike has 3 gears on the front and 7 on the back. The cable pulls from the bottom. I think it's top swing but not sure. Most of it is above the clamp and curves down to slightly below it. The gear shifters are shimano ST-EF51.

Here is a pic of the other side if it helps.



Are there any sites that will tell you compatible parts if you enter your criteria? I've not had much luck on shimano's website. I'd buy an exact replacement if I could but I cant see a model number on it and havent been able to find any that look the same.

Front derailleur clamps come in three common diameters, 1-1/8" (28.6 mm), 1-1/4" (31.8 mm) and 1-3/8" (34.9 mm). The frame you show appears to be standard diameter steel and probably takes a 1-1/8" derailleur clamp. A caliper will confirm that or tell you which of then other two you need.

That is a Shimano Tourney derailleur, Shimano's entry level group. The actual model number will be engraved on the back of the inside plate of the cage but any current Tourney will do.

Frankly, the first thing that bike needs is a good cleaning and lubricating.

Thank HillRider. That makes it a lot easier for me. I've been googling this stuff all day.

Ordered some lube last night. Believe it or not I've already cleaned a ton of gunk off it. A friend of ours had it for the last 3 years as we didnt have room for it. The guy is a bike enthusiast and looks after his own ones really well. Needless to say we're pretty insulted by the state he let it get into. I think he was using it to cycle to work in the winter. It was in pretty much new condition when she gave it to him and now half the parts are covered in rust and need replacing.