In my previous blog post I wrote about my TT bike frame selection. If you haven't read it yet then head over to Part 1: Time Trial Bike Build - Frame ordering. Component selection was considered around the same time that I was selecting the frame since they have to fit onto the frame.
One main factor to consider when buying a frame and components would be the bottom bracket (BB) of your bike. For me, my choice of crank arm is Shimano so my bottom bracket would have to fit Shimano's hollow tech II. I choose BSA for my bottom bracket. The TT frame FM086 from Dengfu had a choice of BB30 and BSA for bottom bracket. Both BB30 and BSA can fit a Shimano crank but I selected BSA for simplicity, to fit a Shimano crank on BB30 you would have to use an adaptor to reduce the bottom bracket shell inside diameter. I didn't like this for two reasons, one it will cost more and two it will most likely squeak after a few months of use and of all things I HATE a squeaky bike. So put this in your consideration on your BB choice and crank arm the next time you are shopping for a new frame or new BB. Less moving parts is always better than more, especially on the section that will take a lot of punishment from your legs.
Derailleur, For deraileur choice I went with Shimano Dura Ace 7900 front and rear. Why not Di2 or why not the new DA9000? It was my wheel choice that limited me to 10 speed DA7900 and not the DA9000. I already own a good set of HED H3C wheels and they only take 10 speed cassette so I can't use the new DA9000 with 11 speed rear cassette. Not Di2 because it just cost too much and again most the new ones are 11 speed.
Crankset, I went with Shimano DA9000 for my crankset. Yes, this is mixing 7900 and 9000 parts. The chain ring size and dimensions of the 11 speed 9000 series and 7900 series are the same but the newer 9000 series is lighter and stiffer plus it looks nicer at the same price. I had to get this new one. Shimano does not recommend you use the new DA9000 crankset with the older DA7900 cassette and derailleur but I have looked at all the technical specifications and they should work together nicely. I will do a review later once I have it all installed and working on my bike. I picked the 53x90 chain ring size as this should be more than enough for me to spin up to about 90 plus cadence. Crank arm length is 170mm, how did I come to that number? I used this website, all you have to do is input your leg length and the program calculates your required crank arm length.
The TT frame can only fit TRP TTV brake set so that was an easy choice, the TRP TTV it is. Dengfu offered two sets for me at US$110 so that was an easy deal, cheapest compared to any online shop. I already know that the TRP TTV brakes are a bit fiddley to setup but I'm sure I can work it out, after all it is based on the V brake which I have used and have worked with on most mountain bikes.
Many of the parts are purchased from online retailers such as eBay, Amazon and Pushys but mostly Wiggle as they price match. I get what I can from them. I won't go into too much detail about the selection of each part or component but if you are interested in the parts list then you can see the table below.
