Using pre existing 27" cantilever mounts for 700c
02-28-24, 07:08 PM
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Using pre existing 27" cantilever mounts for 700c
Any body have a thought on converting a 27 to 700c using the already existing mafac cantilevers? I think that my 1988 Roberts touring was 27 originally, but have been running 700 for as long as I can remember. On my 1970 Charlie Roberts, from eBay.CA , 5 years ago, the center pulls, had no issue going from 27 1/2 to 700c, was worried I might need a drop bolt, but no problems. It’s a really amazing bike, but having had the 27 pasela’s would love to go Veloflex 32’s are Compass 35-38’s
02-28-24, 07:33 PM
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Lots of relevant info here: https://www.bikeforums.net/classic-v...st-merz-2.html
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02-28-24, 08:40 PM
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Try it. You will have to angle the pads down. Watch them carefully as they break in. Will probably need an adjustment once or twice over the life of the pad as it wears. The thin replaceable pads probably will not serve well. I'd expect the top edge to wear to the metal pad holder quite fast. The much deeper one piece disposable unit should work a lot better. And as the pad wears it will try to slip down off the rim with hard braking. Don't let this happen! The pad will be in your spokes! Keep the pad as high as possible on the rim. (Unlike regular calipers where too high means possibly touching the tire and slashing the cord as pad wears.)
700c rims are 4mm lower than 27". I had my Mooney built with the cantis set half way between. I've always had 700c and I have the pad issues I described above to a small level. Totally within reason. (I had no idea which way the market was going to go in 1978. Nor if 700c tires could even be found in the out of the way places my life might take me.)
700c rims are 4mm lower than 27". I had my Mooney built with the cantis set half way between. I've always had 700c and I have the pad issues I described above to a small level. Totally within reason. (I had no idea which way the market was going to go in 1978. Nor if 700c tires could even be found in the out of the way places my life might take me.)
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02-29-24, 12:11 PM
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Any body have a thought on converting a 27 to 700c using the already existing mafac cantilevers? I think that my 1988 Roberts touring was 27 originally, but have been running 700 for as long as I can remember. On my 1970 Charlie Roberts, from eBay.CA , 5 years ago, the center pulls, had no issue going from 27 1/2 to 700c, was worried I might need a drop bolt, but no problems. It’s a really amazing bike, but having had the 27 pasela’s would love to go Veloflex 32’s are Compass 35-38’s
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02-29-24, 12:36 PM
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02-29-24, 12:43 PM
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One factor that hasn't been brought up yet is rim width. If the 700c rim is the same width or narrower than the 27" rim, you have better odds of it working. If the 700c rim is wider, then you may find the canti studs are spaced too close together to make it work.
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