Bicycle Mechanics - dumping the granny gear..

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View Full Version : dumping the granny gear..


nubike
09-27-10, 04:26 PM
I have a 2001 Bianchi veloce road bike with a spindle-type BB and 3 chainring crankset. Is it possible to replace this setup with the Campy ultra torque compact crankset that utilizes only 2 chainrings? Since the compact crankset uses cups to install, is it just a matter of using the existing treads to screw the cups in and then install the crankset? I know I will need a new rear cassette to get the best results, but will I also need a new derailler or can I simply adjust it to accomadate the double chainring? Any answers will be greatly appreciated!


redirekib
09-27-10, 04:38 PM
Since you're getting a new crank I would replace the chain and cassette. You will also definately need a new front derailleur.

fietsbob
09-27-10, 04:39 PM
remove the whole crank and BB, and buy all new stuff .. nothing crosses over AFAIK.
external bearing BBs have their own installation tools to buy also.
including a torque wrench to meet the torque specs.

Might be cheaper to have a shop do the work than buy the tools


nubike
09-27-10, 08:53 PM
Thank you for the reply. So in your opinion what i'm describing is possible?

bikinfool
09-27-10, 09:05 PM
What you're describing isn't even possible to really know WTF you're thinking about. The ultra torque crankset uses a particular bottom bracket setup, really has nothing to do with a double vs triple chainring setup particularly. You just need to learn more. Keep looking for info...

dabac
09-28-10, 01:20 AM
I have a 2001 Bianchi veloce road bike with a spindle-type BB . ... Since the compact crankset uses cups to install, is it just a matter of using the existing treads to screw the cups in and then install the crankset?

Going from a cartridge-tybe BB to an external cup BB is possible. There is a Shimano one that is press fit, but the others screw in, using the same threads. Have the BB shell faced first, external cups are more sensitive to alignment than cartridge BBs.


...and 3 chainring crankset. Is it possible to replace this setup with the Campy ultra torque compact crankset that utilizes only 2 chainrings?

Going from a triple crank to a double crank is also possible. Do not require change of BB type, but will require change of axle length to achieve the ideal chainline. If you intend to change axle length you might as well change BB type while you're at it.


... will I also need a new derailler or can I simply adjust it to accomadate the double chainring?

Don't really know about the FD. As you're going from a wider range of travel to a smaller range of travel I think the current stuff should work. Maybe not as well as possible, but I can't see any immediate showstoppers. Then again, I've only swapped between 3-2-3 on fairly old stuff. There I've gotten away with just about anything.

redirekib
09-28-10, 01:27 AM
What you're describing isn't even possible to really know WTF you're thinking about. The ultra torque crankset uses a particular bottom bracket setup, really has nothing to do with a double vs triple chainring setup particularly. You just need to learn more. Keep looking for info...

Did you miss the "Head Start" bus?

Garthr
09-28-10, 04:28 AM
I have a 2001 Bianchi veloce road bike with a spindle-type BB and 3 chainring crankset. Is it possible to replace this setup with the Campy ultra torque compact crankset that utilizes only 2 chainrings? Since the compact crankset uses cups to install, is it just a matter of using the existing treads to screw the cups in and then install the crankset? I know I will need a new rear cassette to get the best results, but will I also need a new derailler or can I simply adjust it to accomadate the double chainring? Any answers will be greatly appreciated!


You don't need a new crank, just take of the granny ring on your current crank and get a shorter BB. Your triple FD will still work just fine.

fietsbob
09-28-10, 09:12 AM
If its a Campag race triple... [own several]
the right arm has been designed to use a short BB ,
the 3rd ring sits on bosses rather than spacers.. they dont come off .

if the OP finds a older double crankset of same era,
the double sits on the same

111mm [or 115 if a large diameter seat-tube] the right crank arm
is different though from the side
looks similar ... the same 135 crank spider.

If you want the latest stuff, for the 50 34 combination,

then you pay the bike shop to strip out old everything
and buy the whole new set.

2 different sets of tools to remove 1 and install the other,
making a used once tools impractical cost.

nubike
09-28-10, 11:15 PM
Thanks for the reply, bikinfool. And yes I'll keep on looking.