This might be the dumbest idea ever proposed on ST, but I got to thinking: All of my races this year will be flat courses, and I think I can get away with a single chainring setup when it comes to the required gearing. I could go with an 11-28 cassette to give myself a bit wider range of gears if I felt the need. Does anybody do this? I thought it might have some advantages - get rid of the front derailleur, small chainring, shifter, and cable to simplify things, lighten things up, and clean up the aero around the crank a bit. Looking down while on the trainer this morning made me think that the front der is kind of a big aero brick. All I would need would be a set of single chainring bolts and a bar end plug for where the shifter used to be, right? Without a front derailleur, am I going to have problems with the chain falling off the chainring if I’m in the high/low cogs on the cassette?
Is this even worth thinking about?
Thanks for any thoughts. You can all laugh at me as you pass me while I’m walking up the one big hill 2 miles from the end that I forgot about… lol
You will still need something to keep the chain from falling off. I run a single ring on my commuter bike so I have less to deal with, especially when it comes to winter riding. But I have to keep an old derailleur on there to catch the chain. So you will need at least a chain catcher of sorts. Which is too bad. I loved the look of the single front before adding a chain catcher. So clean and sleek. But I hated spinning my peddles with no chain on the rings.
it isn’t worth it because you have to keep the FD on there anyway, or the chain could pop off on a bump.
also you might one day get caught out in a huge head wind and wish you had the inner =)
it might be worthwhile to go single on a hillclimb, since grams start to matter and the slow speeds and tension would reduce the risk of losing the chain
This might be the dumbest idea ever proposed on ST, but I got to thinking: All of my races this year will be flat courses, and I think I can get away with a single chainring setup when it comes to the required gearing. I could go with an 11-28 cassette to give myself a bit wider range of gears if I felt the need. Does anybody do this? I thought it might have some advantages - get rid of the front derailleur, small chainring, shifter, and cable to simplify things, lighten things up, and clean up the aero around the crank a bit. Looking down while on the trainer this morning made me think that the front der is kind of a big aero brick. All I would need would be a set of single chainring bolts and a bar end plug for where the shifter used to be, right? Without a front derailleur, am I going to have problems with the chain falling off the chainring if I’m in the high/low cogs on the cassette?
Is this even worth thinking about?
Thanks for any thoughts. You can all laugh at me as you pass me while I’m walking up the one big hill 2 miles from the end that I forgot about… lol
I tried this, but at what cost? I live at the beach. My only hill is a bridge and I can use my big ring easily up and over. But the 30 knot head wind can kill a man. Climbing rigs? I have seen some interesting builds. Remember Lances down tube shifter? I have seen people cut out “chunks” of their crank arms, rings, and I have even seen people sand/shave down their entire bike to nimble-metal. All things considered, even the pro’s don’t pay this must attention. I did have a double ring mountain bike and I loved it but my legs/weight aren’t what they once were and I need my Big-Small-Baby ring set-up just to survive now. I have seen single rings work out just fine and it “can be done with no front deral.” If you have a good LBS, they can figure it out.
This was a lot more common back in the 80s and 90s. As mentioned the issue is needed a derailler or some type of chain retention device. The other is that after riding with one ring for a while, you realize that the second chain ring can be really, really handy. You may have a nasty headwind on race day.
A couple years back our state tt championship was on a really flat course, so I pulled the small chainring, front derailleur, etc. Fifty yards off the start line I was shifting rapidly through the years which got the chain bouncing and off it went. With nothing to retain it, there was no shifting it back on. I had to stop, dismount and reinstall the chain. (I won my age group anyway … had a TON of adrenalin after that.)
I learned later that the thing to do is find a chainring that’s specifically designed for use as a single chainring. I got one from FibreLyte (a UK company … google them). It has Ionger teeth to retain the chain better. I raced it quite a lot and had no issues at all. Then I got a Vumachrono crankset and didn’t do the single chainring thing anymore.
I liked it. For flat courses, it can’t hurt if you have the right chainring.
Try it yourself first. I don’t know how these other folks shift, but my tri bike has only the big ring up front for two years now and no front derailleur, ZERO missed shifts or thrown chains. I’ve raced this set-up several times, including a “hilly” tri at Lake Boerne, Texas (so called “hill country”), so really not that hilly, but did have a couple short steep hills and plenty of upshifts and downshifts.
I use the friction shift, rather than pre-sets, maybe thats the difference? I run this set-up because brazed-on derailleur mount broke and I’m too cheap to ship the bike back to Guru to have it re-welded. Plus I live in Texas, so pretty much don’t need two chainrings, unless you’re a wimp…
Mandatory 2003 Tour de France prologue reference:
"David Millar (Cofidis) went fast enough, but the loss of his chain near the end probably cost him the win. Interestingly, Millar did not ride with a front derailleur. "
its just a luck thing. if you never coast at all that will usually prevent losing the chain as you keep it tensioned.
your day will come though =)
Try it yourself first. I don’t know how these other folks shift, but my tri bike has only the big ring up front for two years now and no front derailleur, ZERO missed shifts or thrown chains. I’ve raced this set-up several times, including a “hilly” tri at Lake Boerne, Texas (so called “hill country”), so really not that hilly, but did have a couple short steep hills and plenty of upshifts and downshifts.
I use the friction shift, rather than pre-sets, maybe thats the difference? I run this set-up because brazed-on derailleur mount broke and I’m too cheap to ship the bike back to Guru to have it re-welded. Plus I live in Texas, so pretty much don’t need two chainrings, unless you’re a wimp…
Maybe, but I raced this way in CapTexTri, Greater Gator & a local sprint, maybe one or two others (?), and plenty of training miles over sometimes rough roads. Never a thrown chain.
I DO spin ~100rpm and rarely coast, habit from several years of fixed gear commuting. I ride this bike no different than my road or mtn bike since I wasn’t even aware of possible thrown chain. Now that I’m aware watch me ride differently and throw the chain…
I raced like that once too, and didn’t lose my chain either =)
make sure your chainring isn’t too worn, the lower the teeth get the higher the odds of losing it.
Maybe, but I raced this way in CapTexTri, Greater Gator & a local sprint, maybe one or two others (?), and plenty of training miles over sometimes rough roads. Never a thrown chain.
I DO spin ~100rpm and rarely coast, habit from several years of fixed gear commuting. I ride this bike no different than my road or mtn bike since I wasn’t even aware of possible thrown chain. Now that I’m aware watch me ride differently and throw the chain…
I’ve done this for a couple of years. The first year I had nothing on the front and experienced a couple of chain drops while shifting and once in a race. Last year I put the front derailleur back on but left it in the 53. This year since I bought return to center shifters I’m using the front and if its a low wind day I can just run in the 53 for the whole tt. BTW I do use a 11-26 cassette. Using a double I could just use an 11-23.
You´ll have more luck running a single ring without a chain catcher if you flip the RD shifter to friction mode.
Indexed changes make the chain oscillate, and it kind of ´tank slaps´off the chainring. Very frustrating.
You´ll have more luck running a single ring without a chain catcher if you flip the RD shifter to friction mode.
Indexed changes make the chain oscillate, and it kind of ´tank slaps´off the chainring. Very frustrating.
I think that’s the first time I’ve heard some one refer to a tank-slapper on ST…
I’ve only had the start of a tank slapper, coming out of the bottom corner on kilo race bike, pinned the throttle, speed shift to 2nd and as the front end lightened up it started. Put my weight forward and eased off the throttle and it calmed right down. So naturally pinned it again so I could get up to at least 4th gear by the end of the straight away, somewhere north of 200 kph followed by heavy breaking and trail braking down to sub 80 kph for the left hander at the end of the straight. That was FUN.