Heres what I have: '04 Fisher HKEK, 27 speeds.
Here's what I want:'04 Fisher HKEK 9 speed.
Basically I want to ditch the front derailler, and just run a 34 tooth single speed front chain ring.(tall teeth, no shift riser thingies)
The bike shop installed it and said the chain still comes off (so i still need the front derailler). The specs(Salsa) said it could be used with an 8/9 speed rear cassette.
Any I deas?
Dont want full single speed, just trying to get rid of stuff I'm not using...
Thanks, Corey.

A front derailer may help a little but the chain will still fall off. You need a chain guide like one of these: clicky.. (http://www.cambriabike.com/shopdisplayproducts.asp?id=20&cat=Chain+Guides%2FTransit%2FProtctrs) ..

The above link has an assortment of product on it, just look for chain guides. Check your chain length, make sure you don't have too much slack. The bike shop should have removed, or at least suggested removal of chain links if you no longer use anything taller than 34t up front. If the chain is the proper length & rear derailer is in good working order (keeps chain tensioned), your chain should stay in place most of the time without help from a guide or derailer. A good chain guide keeps it on ALL the time.

A front derailer may help a little but the chain will still fall off. You need a chain guide like one of these: clicky.. (http://www.cambriabike.com/shopdisplayproducts.asp?id=20&cat=Chain+Guides%2FTransit%2FProtctrs) ..

The above link has an assortment of product on it, just look for chain guides. Check your chain length, make sure you don't have too much slack. The bike shop should have removed, or at least suggested removal of chain links if you no longer use anything taller than 34t up front. If the chain is the proper length & rear derailer is in good working order (keeps chain tensioned), your chain should stay in place most of the time without help from a guide or derailer. A good chain guide keeps it on ALL the time.
Thanks for the info! I looked, and most of them are for more teeth, but now I know where to start...

Hows the derailer tension when your in first gear? it should be pretty tight....

Your asking the derailer to take up alot of slack .... the chain was shortned, right?

What gear are you in when the chain falls off?

Hows the chain line?

Your front sproket is attached where the middle sproket was.... right?

On my bash around town bike I did what you're wanting. I used a salsa 32 tooth chainring and a salsa bash ring. With the rear derailer adjusted right, the chain stays where its supposed to. You might need a narrower bottom bracket to make sure the front sprocket is centered to the rear cassette. The newer Race Face bottom brackets have some adjustment to them to get your chainrings centered. You went to a shop to get this done?

okie-- lemme help ya out here.

You dont need to run a front derailleur at all. You can use a simple $5.00 part(forgot the name) but i got a spare. No need to pay big bucks for a full on chainguide that weighs a ton and makes noise.

Basically you run your middle ring-- this doohickey on the inside in place of the derailleur and then an outside bash guard to keep the chain from wandering outside.

I ran this for quite some time with no problems and then went to singlespeed. shoot me an email to bugsnbikes@yahoo.com and i will hunt around the parts bin. Are you using a 110bolt crankset?

peace,Tim