Bicycle Mechanics - 105 Triple to FSA Double...

I just bought a Scott CR-1 that is fully equiped with shimano 105 components.(triple chainring)

In order to convert to the FSA Double crank...is it going to be neccessary to....

replace the front derailleur?
back derailleur?
replace the sti shifter/brake levers?


i know i will need a new bottom bracket.

and also.....


if say i only need to replace the front derailleur.....would it be ok to use a Ultegra or Dura-ace front derailleur with my existing compents? (shifters, rear derailleur)

The 105 brifters are double/triple compatible.

For best shifting, you'll need to replace both front and rear derailleurs. The triple derailleurs will work, but not as smooth as can be.

New BB, yes, for shorter spindle length (and FSA crank is probably ISIS).

This might be a stupid question, but why didn't you buy it with a double to begin with??

The 105 brifters are double/triple compatible.

For best shifting, you'll need to replace both front and rear derailleurs. The triple derailleurs will work, but not as smooth as can be.

New BB, yes, for shorter spindle length (and FSA crank is probably ISIS).

This might be a stupid question, but why didn't you buy it with a double to begin with??

my LBS had 2 in stock.........one for $2200 (the one i bought)....a 54...which fits me perfectly.........and one other one that was about $4000 outfited with a full record group, and really nice zipp wheels.

i know i shoulda waited and just bought one online or gone somewhere else or something but after test riding the bike i totally fell in love..............triple crankset and all and ended up just buying it there on the spot. i also wanted a new bike in time for the Seattle to Portland ride.....again not a good excuse.....but i guess im young and dumb.

okay, so... why bag the triple anyway? weight issue? if you don't need the "granny gear" why not ignore it? just curious...

Hmmm nice name... fat a**... sounds like me :lol:

If he wants a double, then go to a double... I am sure he can sell some of the 105 parts off and make some of the cash back...

my LBS had 2 in stock.........one for $2200 (the one i bought)....a 54...which fits me perfectly.........and one other one that was about $4000 outfited with a full record group, and really nice zipp wheels.

i know i shoulda waited and just bought one online or gone somewhere else or something but after test riding the bike i totally fell in love..............triple crankset and all and ended up just buying it there on the spot. i also wanted a new bike in time for the Seattle to Portland ride.....again not a good excuse.....but i guess im young and dumb.

Should have broke the bank and bought the Record bike. Nothing ShimaNo makes even comes close.


Tim

okay, so... why bag the triple anyway? weight issue? if you don't need the "granny gear" why not ignore it? just curious...

1. Lance rides a double.
2. The fsa carbon crank matches my carbon bike
3. I dont have a fat ass



thanks for the help

Going compact means more shifting in front, and we all know that’s not the exactly preferable.
Having FullShịtAhead chainrings makes it even worse.

Going compact means more shifting in front, and we all know that’s not the exactly preferable.
You're the first one in this thread to mention compact. Have you owned a compact double? I shift less in the front with my compact (50/34) than I did with a regular double (53/39) - just about all of my cruising is in the 50, whereas it used to be top end of the 39 / bottom end of the 53 depending on the terrain.

In any case, when a drivetrain shifts nicely, who cares how often you shift it?


Having FullShịtAhead chainrings makes it even worse.
Wow. How insightful. :rolleyes:

You're the first one in this thread to mention compact. Have you owned a compact double? I shift less in the front with my compact (50/34) than I did with a regular double (53/39) - just about all of my cruising is in the 50, whereas it used to be top end of the 39 / bottom end of the 53 depending on the terrain.

In any case, when a drivetrain shifts nicely, who cares how often you shift it?


Wow. How insightful. :rolleyes:

I just presumed he was going compact since he had a triple, and yes. I actually own a compact and I experience a lot of shifting if I want to keep a good chainline.

......... and I experience a lot of shifting if I want to keep a good chainline.Explain that one.

You're the first one in this thread to mention compact. Have you owned a compact double? I shift less in the front with my compact (50/34) than I did with a regular double (53/39) - just about all of my cruising is in the 50, whereas it used to be top end of the 39 / bottom end of the 53 depending on the terrain.

In any case, when a drivetrain shifts nicely, who cares how often you shift it?


Wow. How insightful. :rolleyes:The point is usually made that wth a compact and the greater percentage diff between the rings, that when you shifft from the big to the small you have to often make an additional shift to a smaller cog in the rear relative to a normal 39 small ring.

Chris, what size chainrings are on the FSA double? This does make a difference when selecting a front derailleur. Your triple derailleur may work, but less than ideally.

All Shimano STI shifters except D-A are double/triple compatible.

The rear triple derailleur will work well with the double, snobs may not like the way it looks.

The bottom bracket needs to match up with the crankset, length and pattern.

Al

The point is usually made that wth a compact and the greater percentage diff between the rings, that when you shifft from the big to the small you have to often make an additional shift to a smaller cog in the rear relative to a normal 39 small ring.
Ah yes... the 'extra rear shift'.

Big deal. Takes a split second more. I'd see it as an advantage - the bigger difference between the front chainrings means less overlap in the gears.

Anyway, back on track. This thread isn't about compact doubles... :D

All Shimano STI shifters except D-A are double/triple compatible.

10 speed Ultegra have separate double/triple brifters too.

10 speed Ultegra have separate double/triple brifters too.

Good, that's the way I like them.

Chris, what size chainrings are on the FSA double? This does make a difference when selecting a front derailleur. Your triple derailleur may work, but less than ideally.

All Shimano STI shifters except D-A are double/triple compatible.

The rear triple derailleur will work well with the double, snobs may not like the way it looks.

The bottom bracket needs to match up with the crankset, length and pattern.

Al

The chainrings are standard size for a double (39/53).....its not a compact.

And thanks for actually helping me with my question:)

Is there any reason why a double ultegra front derailleur wouldnt work with my 105 shifters?

Is there any reason why a double ultegra front derailleur wouldnt work with my 105 shifters?
Nope... it'll work fine.