The Spares Company
Club Shop/Regalia
Parent Website
Contact Officials
Machine Registrar
Club Secretary
Membership Secretaries
MPH Editor and Forum Administrator.
Section Newsletters
Technical Databases
Photos
Home
What's new
Latest activity
Forums
New posts
What's new
New posts
Latest activity
Information
Bike Modifications
Machine Data Services
Manufacturers Manuals
Spare Parts Listings
Technical Diagrams
Whitakerpedia (Vincent Wiki)
The Club
MPH Material Archive
Flogger's Corner
Obituaries
VOC Sections
Local Sections
Local Section Newsletters
Miscellaneous
Club Assets
Club History
Club Rules
Machine Data Services
Meeting Documents
Miscellaneous
Essential Reading
Magazine/Newspaper Articles/Letters
Adverts and Sales Brochures
The Mighty Garage Videos
Bikes For Sale (Spares Company)
Log in
Register
What's new
New posts
Menu
Log in
Register
Install the app
Install
Home
Forums
Forums: Public Access
Tech. Advice: Series 'B' / 'C' 500cc/1000cc Bikes
Front brake help please
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="Simon Dinsdale" data-source="post: 175311" data-attributes="member: 58"><p>The front brake on my Rapide was standard and was a very spongy brake. I then fitted twin leading brakes to my Rapide which I machined up myself from cast alloy castings provided to me by a very knowledgeable member / engineer who had them cast 25 plus years ago and I kept the same standard brake cables (which were not that thick) and the standard balance beam. The result was the brake now has no sponge feeling at all and is a great brake which to me shows that the brake cable and balance beam are not the cause of the spongy feeling as those were not changed.</p><p></p><p>Try this. With the bike stationary apply the brake gently until you cannot push the bike forward and so the brake is fully on. Then looking down at the brake arms and apply more preasure on the handlebar brake lever and I bet the brake arms keep moving as you get that spongy feeling at the handlebar. This is because the problem is not the brake cable nor is it the balance beam. The problem is inside the brake drum and is usually either the brake shoes bending or the pivot pins the brake shoes mount onto no longer at 90 degrees to the brake plate and so the brake shoes are over at an angle and so the lining is not parallel to the drum surface as these pins are not well supported in the steel brakeplates.</p><p></p><p>Every old steel brake plate I have ever looked at (and its quite a few) these shoe mounting pins have moved over at a slight angle and one I found was loose and could rotate and so this causes the shoes to then out of alignment. Consider this, the steel brakeplates are only 1/8" thick and so the shoe mounting pins are only mounted and supported along an 1/8" length of the pin. The alloy twin leading brake plates I used are 5/8" thick at the area where the brake shoe pins are mounted so are well supported and cannot bend over or move. That and any other wear like in the brake cam pivot bore will all create the sponge feeling.</p></blockquote><p></p>
[QUOTE="Simon Dinsdale, post: 175311, member: 58"] The front brake on my Rapide was standard and was a very spongy brake. I then fitted twin leading brakes to my Rapide which I machined up myself from cast alloy castings provided to me by a very knowledgeable member / engineer who had them cast 25 plus years ago and I kept the same standard brake cables (which were not that thick) and the standard balance beam. The result was the brake now has no sponge feeling at all and is a great brake which to me shows that the brake cable and balance beam are not the cause of the spongy feeling as those were not changed. Try this. With the bike stationary apply the brake gently until you cannot push the bike forward and so the brake is fully on. Then looking down at the brake arms and apply more preasure on the handlebar brake lever and I bet the brake arms keep moving as you get that spongy feeling at the handlebar. This is because the problem is not the brake cable nor is it the balance beam. The problem is inside the brake drum and is usually either the brake shoes bending or the pivot pins the brake shoes mount onto no longer at 90 degrees to the brake plate and so the brake shoes are over at an angle and so the lining is not parallel to the drum surface as these pins are not well supported in the steel brakeplates. Every old steel brake plate I have ever looked at (and its quite a few) these shoe mounting pins have moved over at a slight angle and one I found was loose and could rotate and so this causes the shoes to then out of alignment. Consider this, the steel brakeplates are only 1/8" thick and so the shoe mounting pins are only mounted and supported along an 1/8" length of the pin. The alloy twin leading brake plates I used are 5/8" thick at the area where the brake shoe pins are mounted so are well supported and cannot bend over or move. That and any other wear like in the brake cam pivot bore will all create the sponge feeling. [/QUOTE]
Insert quotes…
Verification
What was Mr Irving's Christian Name?
Post reply
Home
Forums
Forums: Public Access
Tech. Advice: Series 'B' / 'C' 500cc/1000cc Bikes
Front brake help please
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
Accept
Learn more…
Top