Bottom bracket spindle question
12-09-14 | 09:25 PM
#1
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From: Elwood Indiana
Bikes: they change so much I'm tired of updating this
Bottom bracket spindle question
This issue always confuses me. I just got a sweet deal on a super record (so he says) bottom bracket. The spindle is 70 ss 120, will this fit my 80 merckx professional? I plan on using super record cranks. Not sure what other info I need to add.
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Semper fi
12-09-14 | 09:43 PM
#2
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According to Sutherland's, that would be a pre 1978 spindle for use on a 120 rear spacing. Your Merckx is likely 126. You want one that just says 70 SS.
https://www.minortriad.com/campagbb.html
https://www.minortriad.com/campagbb.html
Last edited by jiangshi; 12-09-14 at 09:48 PM.
12-09-14 | 09:50 PM
#3
According to Sutherland's, that would be a pre 1978 spindle for use on a 120 rear spacing. Your Merckx is likely 126. You want one that just says 70 SS.
Campagnolo bottom bracket info
Campagnolo bottom bracket info
12-09-14 | 09:54 PM
#4
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From: Mountain Brook, AL
Super Record cranks - which year?
Period correct front derailleur, post CPSC w/lip?
If using post '77 cranks and FD, then you want a spindle @ 115.5mm. If you use the shorter pre-CPSC 113mm, then your FD will rub the back of the crank arm. I'm sure you've seen this line across the back of a few.
Actually, is a Merckx a 70mm BB shell width???
Period correct front derailleur, post CPSC w/lip?
If using post '77 cranks and FD, then you want a spindle @ 115.5mm. If you use the shorter pre-CPSC 113mm, then your FD will rub the back of the crank arm. I'm sure you've seen this line across the back of a few.
Actually, is a Merckx a 70mm BB shell width???
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72 Frejus (for sale), Holdsworth Record (for sale), special CNC & Gitane Interclub / 74 Italvega NR (for sale) / c80 French / 82 Raleigh Intl MkII f&f (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 09 Giant TCX0 / 10 Vassago Fisticuff
72 Frejus (for sale), Holdsworth Record (for sale), special CNC & Gitane Interclub / 74 Italvega NR (for sale) / c80 French / 82 Raleigh Intl MkII f&f (for sale)/ 83 Trek 620 (for sale)/ 84 Bruce Gordon Chinook (for sale)/ 85 Ron Cooper / 87 Centurion IM MV (for sale) / 03 Casati Dardo / 08 BF IRO / 09 Dogma FPX / 09 Giant TCX0 / 10 Vassago Fisticuff
Last edited by Ex Pres; 12-09-14 at 10:03 PM.
12-09-14 | 10:18 PM
#5
Ride, Wrench, Swap, Race
Joined: Jan 2010
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From: Northern California
Bikes: Cheltenham-Pedersen racer, Boulder F/S Paris-Roubaix, Varsity racer, '52 Christophe, '62 Continental, '92 Merckx, '75 Limongi, '76 Presto, '72 Gitane SC, '71 Schwinn SS, etc.
Super Record cranks - which year?
Period correct front derailleur, post CPSC w/lip?
If using post '77 cranks and FD, then you want a spindle @ 115.5mm. If you use the shorter pre-CPSC 113mm, then your FD will rub the back of the crank arm. I'm sure you've seen this line across the back of a few.
Actually, is a Merckx a 70mm BB shell width???
Period correct front derailleur, post CPSC w/lip?
If using post '77 cranks and FD, then you want a spindle @ 115.5mm. If you use the shorter pre-CPSC 113mm, then your FD will rub the back of the crank arm. I'm sure you've seen this line across the back of a few.
Actually, is a Merckx a 70mm BB shell width???
I don't think that the spindle length or offset will affect the clearance between crankarm and front derailer cage either way.
If the spindle is shortened, the cage moves inward via adjustment, and the crankarm moves inward by a similar amount by default.
Where the CPSC mods affect this clearance, the crankset does need to match the front derailer, since the outer cage plate is thicker so they made the crankarm sit outward from the chainrings to re-establish clearance there.
Only if the older spindle with newer crank causes chainring interference at the chainstay (which it might) does the spindle length need to be increased, otherwise it's better in terms of overall chainline if the spindle is shortened a little. This because the rider often uses all of the cogs while maintaining pace using the big ring, but has no good reason to use the smallest cogs when using the small ring. Small-to-small gear selection causes multiple problems that big-to-big cross-chaining does not.
So in this case, the OP can simply test-fit the parts to see if chainstay-chainring clearance exists, using the parts at hand.
