My first post...

I have a 27 speed road bike I am using for commuting and want to simplify the mechanics as much as possible.

My question... Is it possible to get rid of my rear derailleur while continuing to use the front derailleur?

what will you use to take up slack?

it would be better to have 3 cogs on the back and a single chain ring up front and remove the FD.

or make it a 9 speed like many people do. put a thin bash guard on to keep your pants from getty dirty and caught in the teeth (or cuff pants like 40 yr old virgin) and remove the small granny gear and front derailleur.

you can leave the 9 cogs in the back or take the cassette apart and put less cogs and make spacers out of pvc pipe.

Actually if you cut up a cassette, you can use the spacers that are already in it, I've done it to a few bikes and it works good.

I did this on a bike I have. I used a chain tensioner I found on an old junk Murray Street Eliminator. It was made by Shimano and had RD-MX 50 stamped on it. It works fine but I've never found or seen another. It was basically a derailleur cage and two pulleys that attached to the dropout. No side to side movement but it had enough chain wrap to allow me to run a 48-38-28 chainring. Sorry I thought I had a picture but I can't seem to find it. I'll post it later if I can.
Paul's Components does make a tensioner called a Melvin. He says you can run two chainrings. Who knows, maybe you can make it work for three.

Since rear shifting is almost always better for me than front (especially with a triple), I add my vote to eliminating the FD and extra chain rings if you are interested in simplifying.

The rear shifting for me has usually been more precise, especially under load.

I thought Shimano used RD to indicate rear derailleurs. Are you sure that it isn't a rear derailleur with the upper and lower limit screws set to keep it from moving?

No it's a tensioner. Here is a picture.

And that would work just as well. Remove your rear shifter and cable and then just use the limit screws to lock the rear derailleur in place aligned with the cog you plan to use.

Going 1X9 or using an three speed hub is a much better solution, IMO. Why keep the clunkiest shift?

There are plenty of better options but I like playing around and exprimenting with something different. The bike above has since evolved into a 3x3 using a Sturmey-Archer hub. I've also made a two speed using a White Industries double cog freewheel. Sometimes it's just about having fun.

Thanks for the responses...

I'm riding 19 miles (one way) on mostly flat terrain along the beach. I am really hauling a$$ in some places. There are also some hills I encounter on my route, which is why I need the small ring. My rear derailleur hasn't been working so I have been forced to use the 3x1 and so far it works well.

Some of you suggested a 1x9 setup... Will a 9 speed setup give me the variety of high and low that my ride requires?

You can use a internally geared hub and a chain tensioner like the Surly Singulator. You will need to use the tensioner anyway if your bike does not have horizontal dropouts.

Then, with the singulator, you might be able to use a front derailleur provided that the chain tensioner can take up as much slack as a rear derailleur can - that will be your limiting factor. My guess is that your front chainrings would need to be rather close in size.

I'm off to Sheldon's gear ratio site to see how this would work.

i have a pisgah set up with one ring in front and 9 cogs in the back. front ring is 36-tooth and the cassette is 11-28 but i can change it to 11-32 if needed.

my big gear is 85.1 inches. i'm running a rigid carbon fork (winwood) and 1.4" slicks (IRC @ 100 psi) so it sorta climbs like a road bike.

ed rader

I set up my hybrid 3x7-speed by turning the RD into a chain tensioner (using the limit screws) and installing a Nexus 7-speed in the back. Works well for me, so I don't see why I couldn't put a single-speed hub in the back instead.

Why not fix/replace the DER? They aren't that expensive.
What's wrong with it?

I have a three speed cogset that I've wanted to use, it just needs a hub to screw on to. I tried a current day BMX hub which used a freewheling single, but alas the cluster threads were too big. Any ideas?

Yes. Check out a gear calculator to see for yourself. I find that a 42t ring and a 8 or 9 speed cassette will get me over most anything.

Figure in in "gear inches" exactly what ratios you need. You will then be able to see if a 1x9 system can accomodate them. I would go for a 1x8, the cogs and chain are thicker and more suited to commuting.
You may need to retain the front mech as a chain-keeper top prevent the chain falling off but you wont need any cable or controls for this.
You can place the single chainring on the middle or outer mounting point of your triple chainset, this will affect the chainline.
Single chainrings are noticably lighter and spin more freely.