Bicycle Mechanics - Shimano 105 Shifters - Compatible with Tiagra Rear Derailleur?

Hi - I have a Lemond Nevada City that I refuse to get ride of but the Sora Shifters need to go. I'm curious if 105 Shifters or even Ultegra shifters are compatible with a 9 speed rear Tiagra derailleur? The front derailleur is a Sora 3 chain ring. The chain is a SRAM something (that I don't mind getting rid of for something with a master link).

Here's the what comes stock:

Brake Levers: Shimano Sora STI Dual Control
Front Der: Shimano Sora Triple
Crankset: SR Superbe, 30/42/52 teeth
Rear Der: Shimano Tiagra SS

Any thoughts or advice (even outside of what I'm suggesting) would be greatly appreciated. I don't have the $$$ for a total upgrade for what it's worth...

Yes, Shimano shifters and rear derailleurs are cross-compatible across groups (with a couple exceptions that don't apply here).

Great. Thanks for helping a newb. Much appreciated. :)

But of course the number of speeds of the shifter, cassette and chain must match.

Shimano rear shifters and derailleurs are compatible across their road and mountain groups and the only exception to this is older Dura Ace which has different actuation rates and some of the newest mountain groups that also have different actuation on the shifters... the derailleur does not care.

Front shifters are group specific in that mountain and road shifters ( Shimano indexed) are not compatible due to different cable pull rates.

105 is the sweet spot in the Shimano hierarchy... it costs less than Ultegra, works beautifully, and is pretty much bombproof and is a popular choice on cross bikes for this reason.

I would call Shimano tech support and give them the model number on your shifters. the newest generation of 105 shifters that you see on 2011 bikes apparently do NOT play nice with the old 105 system and subsequent lower parts. I tried to replace a shifter on a road bike with a busted left 105 shifter and Shimano was back-ordered on the new 105's, so the tech told me that I need to replace it with an Ultegra or one other shifter that's more expensive than a 105 (not Dura-ace), but I can't remember. something with a letter and number in it.

Shimano rear shifters and derailleurs are compatible across their road and mountain groups and the only exception to this is older Dura Ace which has different actuation rates and some of the newest mountain groups that also have different actuation on the shifters... the derailleur does not care.

Front shifters are group specific in that mountain and road shifters ( Shimano indexed) are not compatible due to different cable pull rates.

105 is the sweet spot in the Shimano hierarchy... it costs less than Ultegra, works beautifully, and is pretty much bombproof and is a popular choice on cross bikes for this reason.
I couldn't agree more. I consider the 105 series the Blue Ribbon standard. There are more expensive components, and some are arguably better. But it is hard to find kit that is as practical a value, as the 105 stuff.

Thanks again guys. Much appreciated.

I couldn't agree more. I consider the 105 series the Blue Ribbon standard. There are more expensive components, and some are arguably better. But it is hard to find kit that is as practical a value, as the 105 stuff.

Same applies with Shimano mountain groups... if you want to go long and hard and not worry about a thing use XT instead of XTR and save a bunch of money while you are it.

Shimano rear shifters and derailleurs are compatible.... exception ....some of the newest mountain groups that also have different actuation on the shifters... the derailleur does not care.
I believe Shimano's new 10-speed MTB rear derailleurs are not compatible with 10-speed road shifters. For those who want to use a wide range cassette with 10-speed road brifters, a 9-speed MTB rear derailleur must be used.

I would call Shimano tech support and give them the model number on your shifters. the newest generation of 105 shifters that you see on 2011 bikes apparently do NOT play nice with the old 105 system and subsequent lower parts. I tried to replace a shifter on a road bike with a busted left 105 shifter and Shimano was back-ordered on the new 105's, so the tech told me that I need to replace it with an Ultegra or one other shifter that's more expensive than a 105 (not Dura-ace), but I can't remember. something with a letter and number in it.

That tech didn't know what he was talking about.

That tech didn't know what he was talking about.

+1. 5700 series 105 plays well with the rest of the lines, with the new Dyna-sys mountain line being the exception.