Bicycle Mechanics - Can I convert to a single crank?

I currently have a 2008 Fuji Roubaix with a 50/34 up front and 11-25 (9-speed) in the back. I am sort of new to road biking - this is my first road bike and I bought it in Feb 2009. It seems like 95% of the time (level and moderate hills) I am either on the 50 crank and on the larger 4-5 rings in the back, or on the 34 crank and on the smaller 4-5 rings in the back. Which means for the majority of my ride, I am teetering between the large and small crank. It just seems to make more sense to me to try converting the crank over to a single 40T (or in that ballpark) and not have to constantly monitor my front chainring.

Is it common to do this? I have searched on crankset parts and most of the time I just see double and triple cranksets. (I went to FSA and Truvativ's websites). The way I look at it, if I can convert to a single crank for like $100 or less, it's worth the shot. If it sux, I can always remount the original crank that's on there now.

Quick background: My other bike is a (hybrid) GT Zum with a single chainring (38T) in the front (10-30T in the back, 8-speed) and I never feel like I need more gears.

Sure you can do that, but is it really that much of a bother for you? Everyone has their own riding style and I guess you don't like to use your FD, which is fine. Could you not just leave it set on one and ride there all the time? I suppose as one path you could just remove the FD altogether and one of the chainrings as well. Perhaps you likely thought of that and if so my regrets for the noise ...

I currently have a 2008 Fuji Roubaix with a 50/34 up front and 11-25 (9-speed) in the back. I am sort of new to road biking - this is my first road bike and I bought it in Feb 2009. It seems like 95% of the time (level and moderate hills) I am either on the 50 crank and on the larger 4-5 rings in the back, or on the 34 crank and on the smaller 4-5 rings in the back. Which means for the majority of my ride, I am teetering between the large and small crank. It just seems to make more sense to me to try converting the crank over to a single 40T (or in that ballpark) and not have to constantly monitor my front chainring.

Is it common to do this? I have searched on crankset parts and most of the time I just see double and triple cranksets. (I went to FSA and Truvativ's websites). The way I look at it, if I can convert to a single crank for like $100 or less, it's worth the shot. If it sux, I can always remount the original crank that's on there now.

Quick background: My other bike is a (hybrid) GT Zum with a single chainring (38T) in the front (10-30T in the back, 8-speed) and I never feel like I need more gears.

Before you go mucking about with your gears, find out what your typical cadence is. It's quite likely that, as a new rider, you are often using too high a gear.

if you take away your FD- and a chain ring, u will have a useless sti brake shifter, that alone makes this more hassle then its worth.

A friend did suggest just removing the the FD, but then I still am running the chain at a pretty strong angle most of the time. Also, I think if I did that, I wouldn't be able to get to a low enough gear when I really hit a steep hill.

This isn't a huge concern for me, and basically just a nuisance. But I am posting to see if the parts are cheaply and easily available. If so, then it is worth the time and minimal $ to try it out. My goal is to end up with the perfect drive train for my riding style. I love my Fuji in every other way - it's reasonable comfortable and fast enough for me.

if you take away your RD- and a chain ring, u will have a useless sti brake shifter, that alone makes this more hassle then its worth.
I am talking about just messing with the front. I want to leave the rear alone. My thought is that a 1x9 drivetrain is perfect for me.

Edit: Funny - I replied right before you fixed your post from "RD" to "FD"! :)

I personally feel that 1x9 is just perfect, and maybe it is a good choice for you too. You may need to change your crank though. What crank/bottom bracket do you have?

if you take away your FD- and a chain ring, u will have a useless sti brake shifter, that alone makes this more hassle then its worth.
A useless STI brake shifter? The brake lever will still work fine won't it?

I personally feel that 1x9 is just perfect, and maybe it is a good choice for you too. You may need to change your crank though. What crank/bottom bracket do you have?

Changing the crank is exactly what I'm talking about. I'm not sure how to answer your question exactly, but here is a copy/paste from Fuji's website:

Crankset: FSA Gossamer Compact MegaExo w/ Integrated spindle, 34/50T 7075 AL outer rings
Bottom bracket: FSA MegaExo Exterior Bearing System

The best thine might be to repalce your chainrings with ones of a slightly different size. THe fact that you use your big efront ring with your larger cogs indicates to me that your would find it more useful if your big ring was a little smaller... so you could change it for a 48 or 46 tooth.

The opposite is true of your small ring - you find it more comfortable to use in your smaller cogs, so a slightly larger small ring - like a 36 or 38 tooth might be better.

The reasons behind my suggestion are that (1) you will have more usable gears, and (2) running fron the big ring to big cogs or small ring to small cogs is called "cross-chaining" and it makes your drivetrain less efficient and wears it out faster.

You could also get a new cassette - maybe a 14-25 or something - that allows you to use the harder gears more readily with your large chainring. You said you don't want to change your cassette, but this is sort of an odd thing to say because the cassette is usually easier and cheaper to change, as well as far more frequently changed than the cranks or chainrings.

Good luck!

You could probably use the same crank with just one chainwheel by changing out the bottom bracket. If you want to change the crank look at a standard 53/39 which will get you a higher top speed if you ever need it.

Or head for the hills and learn to use the compact.

You could also get a new cassette - maybe a 14-25 or something - that allows you to use the harder gears more readily with your large chainring. You said you don't want to change your cassette, but this is sort of an odd thing to say because the cassette is usually easier and cheaper to change, as well as far more frequently changed than the cranks or chainrings.

Good luck!
This is some great advice actually. I didn't think about changing my cassette. I guess that way I will be able to stay on my 50 crank for 95% of the ride without crosschaining. I shouldn't have stated that I don't want to change my rear cassette, as I don't really care what will solve the issue, as long as it's cheap and not too difficult. I didn't realize changing the cassette was much more common than changing the crank. Thanks! I'm going to go look at some 9-speed cassettes right now.

Oh, one thing: you mention getting a 14-25 cassette. I currently have a 11-25. So shouldn't I be looking for a 14-30? (or something like that)

Oh, one thing: you mention getting a 14-25 cassette. I currently have a 11-25. So shouldn't I be looking for a 14-30? (or something like that)

If it was me, I would be looking at replacing that large chainring if it is too tall for you. That should put you a little closer to the middle of the cogset when you are on the big ring. Not sure what you can fit, but I would likely be looking for a 48 or so to go on it. Chances are that you will eventually outgrow it, and be back on the 50, if you ride a lot, so don't get rid of it. You should be able to get it done for 30 or 40 bones.

Changing the crank is exactly what I'm talking about. I'm not sure how to answer your question exactly, but here is a copy/paste from Fuji's website:

Crankset: FSA Gossamer Compact MegaExo w/ Integrated spindle, 34/50T 7075 AL outer rings
Bottom bracket: FSA MegaExo Exterior Bearing System

Unfortunately that can't be made to work because of the integrated spindle. For ~$100 you could get a sugino messenger crank and a 103mm sugino square taper bottom bracket.

You could also buy whatever triple crank/bb set floats your boat and take off the inside and outside rings.

Note: I have never actually tried the Sugino messenger route, I run a triple shimano crank with the inside chainring removed and the outside chainring replaced with a salsa crossing guard.

Oh, one thing: you mention getting a 14-25 cassette. I currently have a 11-25. So shouldn't I be looking for a 14-30? (or something like that)

Good question.
I suggested a 14-25 for two reasons:

You probably have a road derailleur (like a Tiagra, 105, or Ultegra) and they are designed to work with a maximum cog size of 27 teeth.

And, you said you are either in the big ring/bigger cogs, or in the small ring/smaller cogs... which indicates that you do not need a wider spread or easier gears, just gears that are more appropriate for you, without losing you current easiest gear.

Thanks for all the great feedback everyone. I learned a lot from this thread. I am going to look into either replacing the front to a single 46-48 crank, or replacing the rear cassette.

LarDasse74, thanks for the input on the RD. I have a 105 RD, and didn't know they are limited to using a 27 tooth max cog. I also get your logic on the new range, so I appreciate the explanation.

One more question to everyone: Any tips on websites that carry mid-range road bike components? Every site I found seems to specialize in high-end components like Dura-Ace and Red. Some Ultegra too, but I am looking for 105/Tiagra level. Also, the only place I have seen single cranks was on fixed gear/single speed supplier sites. I don't have a problem with them, but want to know if there are other options for finding single cranks. Tabor, I have actually seen the Sugino cranks on one of these sites. I will definitely keep that in mind.

Still not sure why you are looking at replacing the entire crankset with a single, when all you have to do is swap either the smaller ring up a few teeth, or the large ring down a few. Either of those options would work for you and come out cheaper, and are easily reversible once you build a little power. That 34/50 split is pretty big, and closing it down a little is all you need to do to get you in the middle of the cogs.

One more question to everyone: Any tips on websites that carry mid-range road bike components? Every site I found seems to specialize in high-end components like Dura-Ace and Red. Some Ultegra too, but I am looking for 105/Tiagra level. Also, the only place I have seen single cranks was on fixed gear/single speed supplier sites. I don't have a problem with them, but want to know if there are other options for finding single cranks. Tabor, I have actually seen the Sugino cranks on one of these sites. I will definitely keep that in mind.

Try Universal Cycles (http://www.universalcycles.com), they rock. They also have that crank and BB I mentioned.


Still not sure why you are looking at replacing the entire crankset with a single, when all you have to do is swap either the smaller ring up a few teeth, or the large ring down a few. Either of those options would work for you and come out cheaper, and are easily reversible once you build a little power. That 34/50 split is pretty big, and closing it down a little is all you need to do to get you in the middle of the cogs.

This is definitely a do-able option, if you get them too close you might have trouble with the FD not having a perfect arc for the difference in diameters of your chainrings.

Still not sure why you are looking at replacing the entire crankset with a single, when all you have to do is swap either the smaller ring up a few teeth, or the large ring down a few. Either of those options would work for you and come out cheaper, and are easily reversible once you build a little power. That 34/50 split is pretty big, and closing it down a little is all you need to do to get you in the middle of the cogs.

Sorry dahoyle, I didn't mean to ignore your response. I do think your option is worth considering too. So now, I am trying to decide between:
1) swap out the current 11-25 rear cassette for a 14-25
2) convert to a Shiguno single crank with ~46 teeth
3) swap the outer crank (currently 50 teeth) with something like a 46

I am trying to figure out the cost of these options, as well as how hard they are to do. I want to do the work myself 'cause I think it will be good experience, and I want to be able to revert back to original specs if I don't like the change.

pkarandi,

Those are all valid options. The other one I would consider is switching to 39/52 rings. This would give you more time on the small ring and less on the big ring.

The cheapest would probably be 3. A 44 or a 46 outer would give you great middle gearing, and you still have the 34 as a bail-out granny. I have a 44 on my middle-triple and I spend 95% of my time in that. I run a near straight 12-21 9speed in back.

You should be able to pick up a Sugino AL 44 or 46 for about 30 bucks. If you want steel, you can get a Surly (or similar) for about 60 bucks.

I just ordered a Sinz 46t chainring that will replace my 50t outer ring. I ordered it from Bens Cycle/Milwaukee Cycle (http://www.benscycle.net/index.php?main_page=index&cPath=75_128_597). I really liked their website, and the guy who helped me (thanks Dan!) on the phone was excellent. Plus, the Sinz will be ~$25 shipped. I originally told Dan that I wanted a 44t and he advised against it, saying it would lower my gearing too much, especially since I am keeping the 34 on there. He also warned me that it may not shift as well as the original ring (I forget his explanation of why). But, it shouldn't matter to me since the whole reason I am buying this chainring is so I will barely ever shift the front.

Thanks for all the help everyone, and I'll post an update after I complete the install! :thumb:

Oh, I forgot to explicitly mention that I decided to go with Option 3. (It's only obvious after you read the whole post).