Campagnolo Crank Conversion Double to Single
#1
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Campagnolo Crank Conversion Double to Single
Sorry if this question has been asked before.
I plan on buying Campagnolo cranks from a friend they're Campagnolo Record cranks with double chainrings.
My question is, will I be able to convert these to single? I don't mind buying a single chainring and shorter bolts to do so. Also, will the Bottom Bracket have any issues?
Thanks for replying!
I plan on buying Campagnolo cranks from a friend they're Campagnolo Record cranks with double chainrings.
My question is, will I be able to convert these to single? I don't mind buying a single chainring and shorter bolts to do so. Also, will the Bottom Bracket have any issues?
Thanks for replying!
#3
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Joined: Nov 2004
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From: Appleton WI
Bikes: Several, mostly not name brands.
In general, it should work. Get some BMX chainring bolts to mount a single ring. Often, the best chainline is obtained by mounting the ring on the inner plateau. One caveat: if your "Record" ctranks are actually "C-Record" you may have trouble with the mounting bolt that goes in the back of the crank arm, as it is different from the other bolts, but perhaps a spacer might allow it to work (never tried it, myself).
#5
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Joined: Apr 2009
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From: New Rochelle, NY
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
[QUOTE=JohnDThompson;16853206]In general, it should work. Get some BMX chainring bolts to mount a single ring. Often, the best chainline is obtained by mounting the ring on the inner plateau. One caveat: if your "Record" ctranks are actually "C-Record" you may have trouble with the mounting bolt that goes in the back of the crank arm, as it is different from the other bolts, but perhaps a spacer might allow it to work...[QUOTE]
+1/2
A few issues to consider.
1- Campagnolo cranks are 135BCD, so your options will be limited to Campag. rings, or analogs made to fit. I don't know of any 135 BMX rings.
2- if they are Record, you have to use the special bolt that mounts to the arm, but can use track or SS chainring bolts for the other 4 positions.
The special bolt will need a 4mm spacer to replace the missing ring regardless of whether you mount the single ring inside or out of the arms. If you don't have a spacer, and are willing to sacrifice a ring you can cut a bolt hole off either ring.
Or you can do something slick, and cut, grind or file all the teeth off the outer ring, then file a bevel on the inner side so it's like one side of a V-pulley. This way it'll make a nice chainguard, and also a safety to re-rail the chain if it wants to fall off on bumps.
+1/2
A few issues to consider.
1- Campagnolo cranks are 135BCD, so your options will be limited to Campag. rings, or analogs made to fit. I don't know of any 135 BMX rings.
2- if they are Record, you have to use the special bolt that mounts to the arm, but can use track or SS chainring bolts for the other 4 positions.
The special bolt will need a 4mm spacer to replace the missing ring regardless of whether you mount the single ring inside or out of the arms. If you don't have a spacer, and are willing to sacrifice a ring you can cut a bolt hole off either ring.
Or you can do something slick, and cut, grind or file all the teeth off the outer ring, then file a bevel on the inner side so it's like one side of a V-pulley. This way it'll make a nice chainguard, and also a safety to re-rail the chain if it wants to fall off on bumps.
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FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#6
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Joined: Dec 2010
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From: Above ground, Walnut Creek, Ca
Bikes: 8 ss bikes, 1 5-speed touring bike
i've got a bunch of road double cranks set up as single. one is a Campy Athena. i use the original big ring with steel singlespeed crank bolts. no problem.
BTW, i've just purchased a new Dura-ace 7900 and have removed the inner ring and will soon have it set up on a new build i am working on.
BTW, i've just purchased a new Dura-ace 7900 and have removed the inner ring and will soon have it set up on a new build i am working on.
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