Can someone explain the difference here? I am currently running a 53T in the front and am wondering what benefit or loss there of if I go with a 54T.
The difference is 1T. Duh!!!
Seriously, play with this: http://www.sheldonbrown.com/gears/ to give you an idea.
Can someone explain the difference here?
1 tooth
I am currently running a 53T in the front and am wondering what benefit or loss there of if I go with a 54T.
53x11 ~ 4.82 wheel revolutions/pedal stroke
54x11 ~ 4.91 wheel revolutions/pedal stroke
Speed difference between the two combinations would be would be / 63600 (in/mile) or .0002666cadencewheel diameter. Something like .6 to .8 mph difference at 90rpm depending on wheel diameter. If you’re running a 12-XX cassette the difference would be slightly less.
There is a long discussion on this subject. Here is the link to the thread. http://forum.slowtwitch.com/…=efficiency;#3500154
In this thread are some links to articles that discuss gearing efficiency with 53 and bigger. The link is to another forum where testing was done on different combinations.
Basically the thought was there were to aspects to explain the efficiency results from testing. First, chain tension driven by gearing. Straightness of the chain.
You will need some time to get through it all 
just swaped out my 53 for 54, and a 44 in place of the 39(?)… I think the 44 might have been a bit optimistic… for the hills, and my motor , can I run a 39 with the 54 or will the throw be to much for the fd?
i am in the process of getting a TT bike (Felt) which will have 54-39 on the front
given that my current road bike as something like 50-34 on it, I am curious to see how it will feel. hope i am not in for a shock!
Depends on the FD, but you should be good with that combo. Most compacts come OEM spec with a 16 tooth difference (50-34). Be aware that the chainring difference may limit your cassette range. I think that Shimano 7800/6600 rear deraulleurs had something like a 29 tooth total range.
Thanks guys. I am trying to decide which to stick with and what benefit I’ll get from going up a tooth. My current FTP is 260 watts.