Using pre existing 27" cantilever mounts for 700c
#1
Full Member
Thread Starter
Join Date: Sep 2017
Location: Oklahoma City
Posts: 244
Bikes: 1985 Roberts SLX, Mercian 531, 1984 Torpado SLX,1981/82 Peugeot PSV-10, 1978 Charlie Roberts full touring, 1970 Charlie Roberts 531 road.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 79 Post(s)
Liked 164 Times
in
61 Posts
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
#2
Senior Member
Join Date: Nov 2013
Location: Southern California
Posts: 1,467
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 801 Post(s)
Liked 754 Times
in
411 Posts
Lots of relevant info here: https://www.bikeforums.net/classic-v...st-merz-2.html
Likes For Piff:
#3
Senior Member
Join Date: Oct 2014
Location: Portland, OR
Posts: 12,909
Bikes: (2) ti TiCycles, 2007 w/ triple and 2011 fixed, 1979 Peter Mooney, ~1983 Trek 420 now fixed and ~1973 Raleigh Carlton Competition gravel grinder
Mentioned: 129 Post(s)
Tagged: 0 Thread(s)
Quoted: 4806 Post(s)
Liked 3,932 Times
in
2,557 Posts
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.)
Likes For 79pmooney:
#4
Senior Member
Join Date: Jun 2012
Location: Stillwater, OK
Posts: 7,828
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 1873 Post(s)
Liked 692 Times
in
468 Posts
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
__________________
2014 Cannondale SuperSix EVO 2
2019 Salsa Warbird
2014 Cannondale SuperSix EVO 2
2019 Salsa Warbird
Likes For shoota:
#5
Senior Member
Join Date: Nov 2013
Location: Southern California
Posts: 1,467
Mentioned: 14 Post(s)
Tagged: 0 Thread(s)
Quoted: 801 Post(s)
Liked 754 Times
in
411 Posts
Likes For Piff:
#6
Bike Sorceress
Join Date: Apr 2008
Location: MPLS
Posts: 761
Bikes: Yes
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 62 Post(s)
Liked 116 Times
in
66 Posts
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.
Likes For Arrowana: