Search for the “New Aero Brake” thread. Look for Andrew Coggan’s posts in the last few pages. He has his P3 set up exactly as you are thinking about.
Cool thanks…I started to go blind reading the posts, but as long as it’s feasibly possible I’m gonna do it.
I just didn’t know if there were any considerations I wasn’t aware of…maybe I will get motivated and kill 2 hours reading that thread…WOW!
David Millar would say “no”. But people do it.
If it’s that flat, the weight savings isn’t going have any effect. It also seems like the small ring might be useful from time to time for warmup and cooldown. The unattractive cosmetics of the bare braze-ons for the FD and downtube boss seem like more of a factor than anything related to performance.
Also, do you plan on staying in South Florida for every event you’re ever going to do? If not, just leaving things properly set up and dialed in seems more prudent than just putting it all on for a ride somewhere else and just hoping it works smoothly.
Are you running, or planning on running a straight block in back? If not, consider that adding a small ring might allow you to do so, giving finer adjustments while in the big ring and the option to use the previously untouched small ring if conditions warrant.
As far as Florida yea I’m here to stay…17 years and have not raced out of the state since the early 90’s. As far as cosmetics I could not care less. I’m putting together a low cost project bike and as I was making a list I thought ‘why the hell am I buying a front derailleur I never use mine anyway’. It’s not a huge deal to buy it, but I thought what the hey I can’t recall the last time I put my chain on the 42.
I am definitely not going fixed gear, but will use a 9 speed rear derailleur. I am not sure if that is what you meant by ‘running’, but in case you meant running afterwards, no. I left the draft fest that is Florida triathlon for road racing and ITT’s(where you actually do individual time trials!). I still frequent ST b/c of all the great knowledge and articles…such an awesome site! I also like to watch SneakySpeed and TrashTalk try and outdork each other…cheap entertainment.
I have had my last 3 TT bikes set up with no front derailler. I have only ever had one issue, well one issue twice, where a race I was doing had a wooden plank across the road over a hole. It was a 3 lap bike course and I dropped the chain the first two times. I then shifted into the middle of the cassette for the third lap to keep the chain straight and it was fine.
Okay great thanks! That stinks about he wood plank…on lap 3 I might have considered a bunny hop;)
build it as a single speed. Not a fixed gear, because those are often expressly prohibited in the rules (but not always). Then you have NO derailleurs, just brakes. My fixed gear TT bike is just my track bike with a set of TT bars installed, and a front brake.
Yea I’m not strong enough to push one gear in all conditions. I’m not sure if I understand the dif. between fixed and single, but I need my rear cluster for shure!
it is possible to run a TT bike with just a single chainring in front, but you really should use a chain guide, which basically your front derailleur is (when it is not shifting your chain).
otherwise, you will most certainly drop your chain during a bump or a shift or both. and it will likely happen at the worst possible time (i.e., an important event). and without a front derailleur, you will have a heck of a time getting the chain back on, as you will have to stop and get off the bike to do it. if the chain flies off on a bike with a front derailleur, some careful shifting and slow spinning often can get the chain right back on, and with little loss of speed.
finally, the weight and aero savings by just taking the front deralleur off is truly trivial, maybe 1 sec per 40k (but likely even less) …
I am definitely not going fixed gear, but will use a 9 speed rear derailleur. I am not sure if that is what you meant by ‘running’,
No, by “running a straight block” I meant using a cluster that has only one tooth difference from each cog to the next, eg 12-13-14-15-16-17-18-19-20, sometimes called a corn cob (if you could construct such a thing these days, it’s not stock for 9sp) vs., say, a 12-23 which has gaps (eg. no 18 cog).
This had more relevance back in the days of 6 and 7 speed clusters, where to get any sort of climbing gear you had relatively big (more than one tooth) jumps between cogs, and a TT rig for flat terrain might give up the easier ratios in order to have those smaller gaps between gears, to be able to find that perfect gear - and the small chainring could still keep you out of trouble in wind or rolling terrain. With 9 and 10 speed clusters, it’s definitely not so much of a factor - but for example on a 9 speed 12-25 you give up the (sweet) 16 tooth cog - (except I think the sweet spot of the 16 is really with a 42 chainring - 70 gear inches, same as today’s 39x15).
Anyway, you should be fine, as long as the chain doesn’t fall off 
There is a device which is sold, which at the moment I an not remember the name, which shifts the front derailleur automatically when it gets to the point where the chain line causes it to shift to a more ‘efficient’ front gear for that chain line (at the top and bottom of the rear derailleur range, it will shift down and up respectively to the small and large chainrings). It looks like a derailleur guide, weighs less than a front derailleur, and requires no cables. If you do a search on ST, you should find it; I just cant remember what it is called.
stpehne J
Found it: Bartol system.
My trainer is setup without a front derailleur. It has never caused a problem for me but I do not have bumps from the road and I never shift to the largest cog. I would not see a problem racing it that way but I am not too sure that the risk would outweigh the weight benefit.
Just as a few others have posted, the biggest issue you have is losing the chain. I was riding a clunker while in college in Buffalo. My front derailleur was never working properly so I just took it off. I thought I might have trouble with out something to guide the chain, but I rode a couple months like this and didn’t have any problems training around town. The first time I got to a race with this setup though, I dropped the chain on a stretch of some pretty poor pavement full of pot holes (you probably don’t have those in Florida). With pushing a little harder like in a race you might be more likely to lose it.
I would not do it. You will lose your chain without something up there holding it in place.