Brake mount issue.
11-20-12, 10:30 AM
#1
Senior Member
Thread Starter
Join Date: Sep 2012
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Liked 0 Times
in
0 Posts
Brake mount issue.
I have a bicycle here that needs front brakes.
The issue is that the original boss/post mount v brake system utilized an pin system to adjust tension that cannot exist with the current setup. The pin tension adjustment system is made up of a two parts- the pin which is the spring in the caliper and anchor hole located on the boss or fork. Usually one or three vertically lined holes which can be used. With the three holed system it is usually with age the spring pin is moved to increased tension. The problem is there are no holes on the boss or fork to mount v brakes with springs.
I haven't access to new bosses - thus Im looking for a brake system that mounts by bosses/posts yet doesn't use the pin tension adjustment system.
Any suggestions?
The issue is that the original boss/post mount v brake system utilized an pin system to adjust tension that cannot exist with the current setup. The pin tension adjustment system is made up of a two parts- the pin which is the spring in the caliper and anchor hole located on the boss or fork. Usually one or three vertically lined holes which can be used. With the three holed system it is usually with age the spring pin is moved to increased tension. The problem is there are no holes on the boss or fork to mount v brakes with springs.
I haven't access to new bosses - thus Im looking for a brake system that mounts by bosses/posts yet doesn't use the pin tension adjustment system.
Any suggestions?
11-20-12, 11:00 AM
#2
Senior Member
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 36,716
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
Mentioned: 131 Post(s)
Tagged: 1 Thread(s)
Quoted: 4747 Post(s)
Likes: 0
Liked 744 Times
in
464 Posts
A number of older DiaCompe and SunTour brakes use a cam behind one arm to adjust tension. The cam is adjusted with a large cone wrench and locked in place when the mounting bolt is tightened.
But, and I'm not sure if any have these stop cams on both sides. I have a few of these brakes and will take a look later on.
But, and I'm not sure if any have these stop cams on both sides. I have a few of these brakes and will take a look later on.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“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.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“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.
11-20-12, 12:21 PM
#3
Senior Member
Join Date: Oct 2009
Location: England, currently dividing my time between university in Guildford and home just outside Reading
Posts: 1,921
Bikes: Too many to list here!
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
Likes: 0
Liked 4 Times
in
2 Posts
The U-brakes used on freestyle bikes and some older mountain bikes work in the way you describe, but the bosses are located above the rim not below it. Some of the older Paul's cantilever brakes adjusted in the same way as U-brakes though, with a spring block which was held in place by the brake bolt, but they fitted conventionally-located bosses. It sounds like you may need something like that.
11-20-12, 12:29 PM
#4
Banned
Working Blind .. send pictures, &/or more Data*,
or go out to bike shop for workers that can see what you have.
U brakes , only other U brakes fit. pivot-post is above the Rim
cantilever/V brakes are on bosses below the rim.
*measure boss location as a radius to the axle..
state that number, and the radius of the rim.
wheel size-type.
or go out to bike shop for workers that can see what you have.
U brakes , only other U brakes fit. pivot-post is above the Rim
cantilever/V brakes are on bosses below the rim.
*measure boss location as a radius to the axle..
state that number, and the radius of the rim.
wheel size-type.
Last edited by fietsbob; 11-20-12 at 12:32 PM.
11-20-12, 01:11 PM
#5
Senior Member
Thread Starter
Join Date: Sep 2012
Posts: 137
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Liked 0 Times
in
0 Posts
The bosses are for cati/vbrakes being below the rim. The bicycles in a mtb with a 26 inch wheel.
Measured from the axle mount on the fork, the distance to the bosses is ~25.5cm or 10 inches.. I'm a bit unsure as to where you mean by, "radius to the axle"
Are there any new v brakes that can be ordered?
Measured from the axle mount on the fork, the distance to the bosses is ~25.5cm or 10 inches.. I'm a bit unsure as to where you mean by, "radius to the axle"
Are there any new v brakes that can be ordered?
11-20-12, 01:39 PM
#6
Banned
Are there any new v brakes that can be ordered?
11-20-12, 02:26 PM
#8
Senior Member
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 36,716
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
Mentioned: 131 Post(s)
Tagged: 1 Thread(s)
Quoted: 4747 Post(s)
Likes: 0
Liked 744 Times
in
464 Posts
I just checked, and I have some DiaCompe 987 and 986 brakes with spring adjusting cams on BOTH sides. These will work fine on bosses without spring holes. I can give you a good deal on either (typically the 986 us used in front, and the 987 (low profile) in the rear.
If you're interested send me an email either through BF or via the contact link at the Chain-L site.
If you're interested send me an email either through BF or via the contact link at the Chain-L site.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“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.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin
“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.
