Would like to replace my double with a triple,
#1
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From: Hot-Lanta
Bikes: 2007 Specialized Tarmac (sold) 2009 Specialized Hardrock (sold), 2014 Rivendell Sam Hillborne (sold), 2025 BMC Roadmachine 01 Two
Would like to replace my double with a triple,
but how difficult is this to do and which triple would you guys recommend?
I have a 2007 Specialized Tarmac, and I love the bike, but age and bad knees have suggested that I add one more gear for my uphill runs. I don't want to buy another bike especially since I also have a Rivendell for most of my commuter rides, so I'd like the Tarmac to be a bit more forgiving on these Georgia hills when I trade off and use it as my commuter at times.
I have a 2007 Specialized Tarmac, and I love the bike, but age and bad knees have suggested that I add one more gear for my uphill runs. I don't want to buy another bike especially since I also have a Rivendell for most of my commuter rides, so I'd like the Tarmac to be a bit more forgiving on these Georgia hills when I trade off and use it as my commuter at times.
#2
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From: Pittsburgh, PA
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Which Tarmac model do you have and what is it's current crank and bottom bracket? The conversion is practical but which replacement crank and/or bottom bracket type depends on what you now have.
#3
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From: Upstate NY
Bikes: Bianchi San Mateo and a few others
It's not difficult, but you'll need more than just a crankset. You'll also need a triple front derailleur, a triple-compatible shifter, and a long cage derailleur to handle more chain slack that comes with a wider gearing range.
#4
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From: Dublin, Ireland
Bikes: Bianchi Ti Megatube; Colnago Competition; Planet-X EC-130E; Klein Pulse; Amp Research B4; Litespeed Catalyst; Trek Y11
Also, depending on what you have now, you might consider a different cassette, and/or a compact crankset. Using a compact crankset would be easier than installing a triple; simply swapping in a cassette would be a *lot* easier than a triple.
#5
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not difficult, but you can use a compact crankset and an 11-32 or 12-32 cassette and get a similar gear
for knee issues also look into going one size shorter crank arm eg 172->170mm. This really helps as knee goes through a smaller ROM
#6
I'm assuming standard drop bars. What groupset are you using?
Do you have a "compact" crankset? 34x(something) 110bcd?
Not all of the current Shimano groupsets support a 3x option. Campagnolo generally does allow 3x for their shifters.
But, your change is likely going to take at least:
Do you have a "compact" crankset? 34x(something) 110bcd?
Not all of the current Shimano groupsets support a 3x option. Campagnolo generally does allow 3x for their shifters.
But, your change is likely going to take at least:
- New Crankset
- New Front Derailler (cyclocross, not MTB)
- New Left Shifter
#7
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From: Mountain View, CA USA and Golden, CO USA
Bikes: 97 Litespeed, 50-39-30x13-26 10 cogs, Campagnolo Ultrashift, retroreflective rims on SON28/PowerTap hubs
#8
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From: Hot-Lanta
Bikes: 2007 Specialized Tarmac (sold) 2009 Specialized Hardrock (sold), 2014 Rivendell Sam Hillborne (sold), 2025 BMC Roadmachine 01 Two
I'm assuming standard drop bars. What groupset are you using?
Do you have a "compact" crankset? 34x(something) 110bcd?
Not all of the current Shimano groupsets support a 3x option. Campagnolo generally does allow 3x for their shifters.
But, your change is likely going to take at least:
Do you have a "compact" crankset? 34x(something) 110bcd?
Not all of the current Shimano groupsets support a 3x option. Campagnolo generally does allow 3x for their shifters.
But, your change is likely going to take at least:
- New Crankset
- New Front Derailler (cyclocross, not MTB)
- New Left Shifter
Brakeset Shimano Ultegra brakes, Shimano Ultegra levers
Shift Levers Shimano Ultegra
Front Derailleur Shimano Ultegra
Rear Derailleur Shimano Dura-Ace
Crankset FSA SL-K, 39/53 teeth
Bottom Bracket FSA MegaEXO
Rear Cogs 1-speed, 12 - 27 teeth
Chain Shimano Ultra
#10
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From: Mission Viejo
Bikes: 1986 Cannondale SR400 (Flat bar commuter), 1988 Cannondale Criterium XTR, 1992 Serotta T-Max, 1995 Trek 970
Specialized made a Tarmac triple in 2007. You can mirror the components that are on that bike or get comparable ones. According to bikepedia, the rear derailleur us a Dura Ace and the cassette is a 12-27. The crank is an FSA 30/39/53. I just went to a triple and going with a 30t helps a lot.
For the time being, you could just get the crankset/bb, front derailleur, and shifters (new chain) and see how it goes. I'm sure you can find everything you need on eBay for less. I'm not sure if it is 6600 or 6700. You could probably go to 105. Keep in mind your components are used at this point, so you are not losing anything finding good used parts.
John
For the time being, you could just get the crankset/bb, front derailleur, and shifters (new chain) and see how it goes. I'm sure you can find everything you need on eBay for less. I'm not sure if it is 6600 or 6700. You could probably go to 105. Keep in mind your components are used at this point, so you are not losing anything finding good used parts.
John
#11
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From: Pearland, Texas
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#12
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Why not just switch your standard 39/53 crankset to a compact 34/50t ? That would be the most straight forward option. Then you can keep all your other components. And then sell the standard crankset and recoup some money.
Yes. Do check beforehand that you can lower your FD to the correct position for a compact.
Yes. Do check beforehand that you can lower your FD to the correct position for a compact.
Last edited by trailflow1; 03-29-17 at 10:26 AM.
#13
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From: Cedar Rapids, IA
Bikes: 1997 Rivendell Road Standard 650b conversion (tourer), 1988 Schwinn Project KOM-10 (gravel/tour), 2013 Foundry Auger disc (CX/gravel), 2016 Cannondale Fat CAAD 2 (MTB/winter), 2011 Cannondale Flash 29er Lefty (trail MTB)
I like triples, but I agree that a compact (50/34) or subcompact (46/30 or similar) double crankset would be cheaper and easier than converting this bike to a triple.
If you want even lower gears, you can use a 9-speed MTB rear derailleur to fit a larger cassette, as big as an 11-36. It will index 10 speeds perfectly with your 10 speed Ultegra shifter.
I bet that this configuration (wide range double) would be cheaper than going to a triple. Mostly because you don't have to buy a new left shifter.
Wide range double:
compact or subcompact crankset, matching bottom bracket (keep the front derailleur)
MTB cassette
MTB rear derailleur (XT level RD-M772 or XTR level RD-M972 are great picks)
new chain
Triple:
triple crankset, matching bottom bracket
new FD
new left shifter
new RD (medium cage)
new chain
If you want even lower gears, you can use a 9-speed MTB rear derailleur to fit a larger cassette, as big as an 11-36. It will index 10 speeds perfectly with your 10 speed Ultegra shifter.
I bet that this configuration (wide range double) would be cheaper than going to a triple. Mostly because you don't have to buy a new left shifter.
Wide range double:
compact or subcompact crankset, matching bottom bracket (keep the front derailleur)
MTB cassette
MTB rear derailleur (XT level RD-M772 or XTR level RD-M972 are great picks)
new chain
Triple:
triple crankset, matching bottom bracket
new FD
new left shifter
new RD (medium cage)
new chain
#14
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Posts: 777
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From: Hot-Lanta
Bikes: 2007 Specialized Tarmac (sold) 2009 Specialized Hardrock (sold), 2014 Rivendell Sam Hillborne (sold), 2025 BMC Roadmachine 01 Two
I like triples, but I agree that a compact (50/34) or subcompact (46/30 or similar) double crankset would be cheaper and easier than converting this bike to a triple.
If you want even lower gears, you can use a 9-speed MTB rear derailleur to fit a larger cassette, as big as an 11-36. It will index 10 speeds perfectly with your 10 speed Ultegra shifter.
I bet that this configuration (wide range double) would be cheaper than going to a triple. Mostly because you don't have to buy a new left shifter.
Wide range double:
compact or subcompact crankset, matching bottom bracket (keep the front derailleur)
MTB cassette
MTB rear derailleur (XT level RD-M772 or XTR level RD-M972 are great picks)
new chain
Triple:
triple crankset, matching bottom bracket
new FD
new left shifter
new RD (medium cage)
new chain
If you want even lower gears, you can use a 9-speed MTB rear derailleur to fit a larger cassette, as big as an 11-36. It will index 10 speeds perfectly with your 10 speed Ultegra shifter.
I bet that this configuration (wide range double) would be cheaper than going to a triple. Mostly because you don't have to buy a new left shifter.
Wide range double:
compact or subcompact crankset, matching bottom bracket (keep the front derailleur)
MTB cassette
MTB rear derailleur (XT level RD-M772 or XTR level RD-M972 are great picks)
new chain
Triple:
triple crankset, matching bottom bracket
new FD
new left shifter
new RD (medium cage)
new chain
I'd love it if I could just put on a compact or subcompact crankset. At this point I don't need a drastic change, perhaps when I hit 60 I may, but for now I may be able to get by for a few more years with a smaller crankset if it would make a noticeable difference on the hills.
#15
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From: Roswell, GA
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#16
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From: Wisconsin
Bikes: 2012 Salsa Casseroll, 2009 Kona Blast
I agree. If that doesn't provide a low enough gear, maybe switch the cassette to an 11 - 32 or 11 - 34, provided your derailleur allows for that, otherwise, switch to a mountain derailleur. I think older ones were compatible with road shifters.
#17
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From: Cedar Rapids, IA
Bikes: 1997 Rivendell Road Standard 650b conversion (tourer), 1988 Schwinn Project KOM-10 (gravel/tour), 2013 Foundry Auger disc (CX/gravel), 2016 Cannondale Fat CAAD 2 (MTB/winter), 2011 Cannondale Flash 29er Lefty (trail MTB)
In that case something like this might be helpful: https://wickwerks.com/products/fit-link-adapter/
If the braze-on mount isn't too high, I recommend using the Shimano FD-CX70 cyclocross front derailleur. It's designed for smaller rings, like 50t or 46t.
I recently put a triple (90s Deore M550 48/38/28) on a steel race frame (90s Giordana), and the braze-on tab was just fine for a new Claris FD-2403 to shift those smaller rings. The frame is a stage racer, designed for 52/39. But I'm building it for a friend for his first RAGBRAI, so the triple will be way better for him on the hills.
Just saying that the braze-on FD tab may reach a crankset with smaller rings just fine. Or it may not. Best of luck!
#18
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From: Mt.Diablo
Bikes: Klein, Merckx, Trek
These "convert to triple" threads come up all the time in here. Once folks realize how complicated it is, most of them change their minds.
It would almost be easier to sell your bike and get one that was built with a triple.
But the compact plus 34t cassette is a nice option with far fewer complications.
It would almost be easier to sell your bike and get one that was built with a triple.
But the compact plus 34t cassette is a nice option with far fewer complications.
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