Classic & Vintage - Problem with a Super Record Front derailleur

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cadillacmike68
06-30-07, 09:46 PM
I just got a SR front derailleur for my 1978 Raleigh Professional - which has 1973 or 1974 era Record cranks. The cranks have a 3 in a diamond engraved on the inside. (I had them from a 74 or 75 Motobecane le Champion that got hit by a car). Mt old derailleurs were NR Patent 72 in back and a flat cage Record in front (from the same le Champion). The flat cage Record had no problems, but this drilled out SR front derailleur with that damned "safety lip" is not allowing me enough clearance b/w the outer cage and the crank arm in 12th gear. Either the chain rubs against the inside of the outer cage plate or the outside of the cage plate hits the crank arm. I'm running a Regina Oro chain and freewheel and remember that when I first got the bike 30 years ago the rear derailleur's inner cage plate hit the spokes in 1st gear. So the store added a small spacer - maybe 1mm or 2mm to the hub before the freewheel is attached. I know that this caused the freewheel to move that amount right, and this might be causing the vexing front cage problem, but I didn't have this problem with the old flat cage Record derailleur.
Any ideas?? Maybe a rear spacer half the width of the current one? I think I recall a posting on a web site that mentioned that the front crank spacing was increased to accomodate the safety lip on the curver plate front derailleurs, but I can't remember the site. I'd like to use the SR front changer, but don't want to wear a groove in my crank arm either.
found that web site:
http://www.velo-retro.com/tline.html
Campy lengthened the BB spindle 2.5mm to accomodate the post '77 CPSC lip, with a corresponding change to the crankarm.
You could try rotating the derailler on the seat tube; I try and set them up on a centerline of the chain running on the middle cog, then finetune from there. It's a little trial and error to find the best spot. Also, heightwise, the outer cage edge just needs to clear the teeth of the outer ring, 1/16-1/8 of an inch.
Sometimes it helps to bend that outer, front leading edge in a hair.
cadillacmike68
07-01-07, 06:58 PM
You could try rotating the derailler on the seat tube; I try and set them up on a centerline of the chain running on the middle cog, then finetune from there. It's a little trial and error to find the best spot. Also, heightwise, the outer cage edge just needs to clear the teeth of the outer ring, 1/16-1/8 of an inch.
Sometimes it helps to bend that outer, front leading edge in a hair.
I'm this close to flattening it with a large hammer!
I can get it closer to the outer ting (lower) by a bit, it's a PITA trying to adjust when the spring is working against you. as far as the angle, my logic indicates that the outer edge of the cage should be exactly parallel to the crank arm to gain the most usable room.
BTW, I chacked the catalog 17 - circa 1974 - BEFORE the CSPC BS against catalog 18, 1985 - after said nonsense, and the BB axle length measurements from the catalog, as well as the P/Ns of the crank arms are the SAME?!? I can see them making a small adjustment to the crank arm - by the way - does anyone know exactly what they did?? but to have the EXACT same measurements in the details of the BB axle / spindle tells me that the axles were not changed ?!?!?!?
The spindle length was increased from 112mm (BSC) /113mm (Ital) pre '78 to 114.5mm/115.5mm in '78.
1978 - C.P.S.C. (Consumer Product Safety Commission) mandates changes to NR/SR. Included are a front derailleur lip, 2.5 mm increase in spacing between crank spider and arm to clear the front derailleur lip with corresponding increase in bottom bracket axle length, a curved quick release lever and ball-end added to quick release conical adjuster, dome-shape added to quick release cam lever on brake calipers, plastic covering added to the wheel guides on the brake shoes, and plastic safety-shields added to rear derailleur screws. The word "Patent" is changed to "Brev." on the chainring, chainring bolts and crank dust cap.
cyclotoine
07-01-07, 07:06 PM
The axles were in fact changed. They were 2.5mm longer in the case of record for road doubles, however the effective length added to the drive side is 2mm. As the center is widened by 1mm which would add 0.5mm to both sides.
See:
http://www.minortriad.com/campagbb.html
You should either grind off the lip or purchase the proper derailleur. I have one, of course it has no holes and does not have the black arms... PM if interested.
repechage
07-02-07, 06:23 AM
BTW, I chacked the catalog 17 - circa 1974 - BEFORE the CSPC BS against catalog 18, 1985 - after said nonsense, and the BB axle length measurements from the catalog, as well as the P/Ns of the crank arms are the SAME?!? I can see them making a small adjustment to the crank arm - by the way - does anyone know exactly what they did?? but to have the EXACT same measurements in the details of the BB axle / spindle tells me that the axles were not changed ?!?!?!?
The posts indicating that the crank spindle length changed are correct and for a time the part numbers stayed the same Campagnolo made many "running changes", but for you, the problematic change as the dimension from the outer chainring to the crankarm increased as well to clear the lip. Not much but just a bit. On later cranks besides the date code, the machining is different, the taper is actually set farther away from cenerline of the bike than with the later stuff, Campagnolo juggled a number of dimensions at the changeover.
I run a Super Record front changer with OLD crank Campagnolo crank arm on an old soldier bike, (1970+/-) the outer cage must be straight and parallel to the ring, the forward lip is tweaked just a bit, to clear. I used a small screwdriver blade and a small cresent wrench to do the work, it also assists in moving the chain down to the small ring faster. If I was not desperate at the time in 1986, I would have used the correct unit. I run the cage 3 to 4mm above the big ring for reference.
cadillacmike68
07-02-07, 08:33 AM
The axles were in fact changed. They were 2.5mm longer in the case of record for road doubles, however the effective length added to the drive side is 2mm. As the center is widened by 1mm which would add 0.5mm to both sides.
See:
http://www.minortriad.com/campagbb.html
You should either grind off the lip or purchase the proper derailleur. I have one, of course it has no holes and does not have the black arms... PM if interested.
Thanks, I have the flat cage front derailleur to match the older crank arms. When I bought the bike, the dealer put my old cranks, derailleurs and pedals on it, to save me some short in supply cash. Neither of us knew back then that they made a spacing change on the crank arms and a bb axle change. The bike has the newer Nouvo Record BB set with the supposedly longer axle, but the cranks were from 73 as per the date stamp. This all worked fine for years but with my needing a rear freewheel spacer (needed because I had the dealer remove the horrible clear plastic "spoke protector" back in 78) which pushes out the cogs a bit combined with the lipped SR drilled cage front derailleur, it is proving mighty diff1cult to get everything to clear. First, I'm going to try and find a slightly narrower spacer, then I'll try flattening ot tweaking the front of the cage as described. I could always try to buy a crank arm from 78, but that's expensive.
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