Update - Double chainring -yikes

[violette]

Went to the LBS. Told me changing the Chainring to a 50/34 would make a big difference, the only thing; I would lose my carbon crank. He changed it, I went for a drive, ALMOST NO DIFFERENCE. He scratched his head and said: I can change the cassette to a Mtn bike, but you'll lose your Ultegra derailer, but you'll have your carbon crank back. I couln't lose that , but after thinking about, I said DO IT!

What a difference. It's even better than my triple, but the bike is a bit heavier. I spent a total of 4 hrs waiting for him to do the chainring, put it back on and then cassette.

[Andrea]

So now you have a 50/34 with a MTB cassette in the back? or is it your previous 53/39 with the MTB cassette?

Either way, glad to hear you got it all sorted out.

[OakLeaf]

Glad you're happy! What is the gear range on your new cassette?

I'd be surprised if you really noticed the weight - it should only be a couple of hundred grams heavier. About the same as a tool kit, or a cell phone and 2-3 gel packs. Noticeable when you lift the bike, but not so much when you're riding.

[violette]

The chainring is still 53/39, but the cassette, I'm not sure, it's got more rings than the other one.

[ilima]

FYI: There are compact cranksets with carbon crankarms. I have one, FSA's SL-K compact. They are available. Did the shop just not want to order one for you?

In terms of gear inches, there isn't much difference between a 34 chainring and a 27 cog (road setup) and a 39 chainring and 32 cog (road/mtn setup): 33 vs. 32 gear inches. One big difference between the two set-ups is the weight, however, which may more than negate the slight gearing advantage the road/mtn setup has.

[violette]

FYI: There are compact cranksets with carbon crankarms. I have one, FSA's SL-K compact. They are available. Did the shop just not want to order one for you?

In terms of gear inches, there isn't much difference between a 34 chainring and a 27 cog (road setup) and a 39 chainring and 32 cog (road/mtn setup): 33 vs. 32 gear inches. One big difference between the two set-ups is the weight, however, which may more than negate the slight gearing advantage the road/mtn setup has.

Two LBS called FSA and they don't have them. He said something about I have a 9 spd 130mm and now they make 110mm 10 spd.

[ilima]

Two LBS called FSA and they don't have them. He said something about I have a 9 spd 130mm and now they make 110mm 10 spd.

Standard cranksets use a 130mm bolt circle diameter. The smallest chainring possible is 38 teeth.

Compact cranksets use a 110mm BCD, which allows a smallest chainring of 34 teeth.

FSA advertises their cranksets as 9/10 speed compatible.
http://road.fullspeedahead.com/fly.aspx?layout=product&taxid=53&pid=292

If you're happy with your set-up now, I wouldn't worry about it.

[aicabsolut]

Standard cranksets use a 130mm bolt circle diameter. The smallest chainring possible is 38 teeth.

Compact cranksets use a 110mm BCD, which allows a smallest chainring of 34 teeth.

FSA advertises their cranksets as 9/10 speed compatible.
http://road.fullspeedahead.com/fly.aspx?layout=product&taxid=53&pid=292

If you're happy with your set-up now, I wouldn't worry about it.


Two LBS called FSA and they don't have them. He said something about I have a 9 spd 130mm and now they make 110mm 10 spd.

Now I'm curious about what they did put on your bike the first time they swapped things....