Tiagra 9sp. with 7sp. freewheel ???
 

I received a Tiagra 9sp. RD for next to nothing, will it work on a 7 speed Shimano HG freewheel with Shimano 7sp. SIS shifters. I would think that as long as the limit screws are adjusted correctly it would work with the range I need. I'm sure there are plenty of you guys out there who built a budget project and tried all kinds of combinations as the parts became available.

Depends. If your largest cog is around 27 or 28 teeth it'll work fine. If your largest cog is 32 or 34 teeth the derailleur pulley will rub.

Yeah I've got a 28 on there now. I was considering getting one of the megarange freewheels but thats quite a jump to the big cog. I'll give it a try. Thanks..

Just a follow up on this thread....I put the RD on and a new freewheel along with a new chain and it works beautiful. A little fine tuning and off I went...

Keeeeerect!

Rear derailers don't care how many speeds, that's just marketing.

Sheldon " http://sheldonbrown.com/speeds " Brown