midlife Posted February 17, 2020 Report Share Posted February 17, 2020 (edited) Was at a trial yesterday and a very kind person gave me a tip. He said that if I turned the front brake arm so that it was pointing forwards that it would work better. He then tried to explain that if the top shoe grips before the bottom shoe the brake works better. All I want to know is he talking p*** Edited February 17, 2020 by midlife Quote Link to comment Share on other sites More sharing options...
faussy Posted February 17, 2020 Report Share Posted February 17, 2020 Think he's talking p****. The hub doesn't know which shoe is touching it, and if your complete assembly is working correctly, both shoes should touch at the same time 1 Quote Link to comment Share on other sites More sharing options...
feetupfun Posted February 18, 2020 Report Share Posted February 18, 2020 Yes Quote Link to comment Share on other sites More sharing options...
midlife Posted February 18, 2020 Author Report Share Posted February 18, 2020 If both shoes have the same contact area what shoe it makes no difference what shoe is the lead shoe because they are not directional Quote Link to comment Share on other sites More sharing options...
faussy Posted February 18, 2020 Report Share Posted February 18, 2020 (edited) 13 hours ago, b40rt said: If turning the arm around generates more force onto the leading shoe, the brake will be more powerful ?? Turning the arm forward generates LESS! force, because theres less leverage on the leading shoe... You're talking about 5% here btw, but it is less The argument is that a forward arm makes the leading shoe touch first because a forward arms makes the leading shoe move further (hence the less force), which is the case on a new set of shoes, but on a brake that has been bedded in, both shoes will touch at the same time, meaning its impossible to make the leading shoe touch first Edited February 18, 2020 by faussy Quote Link to comment Share on other sites More sharing options...
cleanorbust Posted February 18, 2020 Report Share Posted February 18, 2020 This reminds me of a debate that went on in Motor Cycle weekly some decades ago about the relative effectiveness of a curved brake arm and a straight one. The theory was that an arm made in an arc shape between the pivot point and the cable attachment provided more leverage than one which was straight. I think the theory was debunked by the technical gurus of the day. 1 Quote Link to comment Share on other sites More sharing options...
faussy Posted February 18, 2020 Report Share Posted February 18, 2020 33 minutes ago, b40rt said: Talking siht, think all the head banging has affected your ability to research before commenting. It's called self servo effect. @faussy https://www.google.com/search?q=servo+effect+in+drum+brakes&oq=servo+effect&aqs=chrome.1.69i57j0l15.6896j0j4&sourceid=silk&ie=UTF-8 Talking ****? I know what the effect is! Looks like you didn't before you had to go to google. Thats the whole idea for twin leading shoes, for which im not arguing!!! Did you read my post? The OP wanted to know the effect the direction of the brake cam has on the leading shoe, and i was explaining the difference! The leading shoe will always be the leading shoe, but changing the direction the cam rotates on the leading shoe effects the force that it applies to the hub. Im starting to think this is all over your head. Quote Link to comment Share on other sites More sharing options...
faussy Posted February 18, 2020 Report Share Posted February 18, 2020 (edited) 30 minutes ago, section swept said: So, what if the front brake plate is a sliding slot affair instead of a brake anchor arm. There I’ve said it ‘ brake anchor arm ‘ which is what most of us have, makes not a jot of difference to the braking effect of the shoes. What some bright spark is going on about is a brake torque arm such as you would have on the rear brake on many m/x bikes....here the brake anchor arm is attached to the frame and not the swinging arm, which allows the brake plate to move slightly with suspension movement independently of the swinging arm. Many leading link front forks Greeves, DOT etc had such an arm to attach to the brake plate. Brake shoes do have a leading and trailing edge. Conventional front single action brake plates have one brake fulcrum (the lever that the cable attaches to) and a fixed pivot for the other end of the shoe. By convention in all of this type of design, as the fulcrum is turned by the rider pulling the brake lever the brake shoe moves out towards the drum surface. The other end of the shoe only pivots about the fixed pivot post/shaft and so only gets to touch the drum surface when the shoe has significantly worn. This same science applies to all single fulcrum operated brakes, that is why we have twin leading shoe front brakes on race bikes and Honda used a twin leading shoe effort on some their m/x and enduro machines and ditto Yamaha. Check out Google for explanatory diagrams etc before loosing off ‘ah buts’. ???? The guy has an SWM, his anchor arm is fixed. You're also arguing something completely different, the benefits of twin leading shoes Edited February 18, 2020 by faussy Quote Link to comment Share on other sites More sharing options...
faussy Posted February 18, 2020 Report Share Posted February 18, 2020 (edited) 1 minute ago, b40rt said: Google explains it so well, and with pictures to make it easier for some of us to understand . Come on, lets see googles answer then. All you're talking about is the servo effect and the multi leading shoes, thats not the discussion Edited February 18, 2020 by faussy Quote Link to comment Share on other sites More sharing options...
b40rt Posted February 18, 2020 Report Share Posted February 18, 2020 Just now, faussy said: Come on, lets see googles answer then Click on the link above. Self servo effect. 1 Quote Link to comment Share on other sites More sharing options...
faussy Posted February 18, 2020 Report Share Posted February 18, 2020 Just now, b40rt said: Click on the link above. Self servo effect. That doesn't answer the original posters question...... Quote Link to comment Share on other sites More sharing options...
b40rt Posted February 18, 2020 Report Share Posted February 18, 2020 7 minutes ago, faussy said: That doesn't answer the original posters question...... The o p didn't obviously understand the conversation ! FWIW, Danillo Gallizi has a forward facing brake arm, he's probably just a slave to fashion. Quote Link to comment Share on other sites More sharing options...
faussy Posted February 18, 2020 Report Share Posted February 18, 2020 (edited) 6 minutes ago, b40rt said: The o p didn't obviously understand the conversation ! FWIW, Danillo Gallizi has a forward facing brake arm, he's probably just a slave to fashion. So is that your answer? Fashion? What was the link to google all about then? Whats your explanation? Edited February 18, 2020 by faussy Quote Link to comment Share on other sites More sharing options...
b40rt Posted February 18, 2020 Report Share Posted February 18, 2020 2 minutes ago, faussy said: So is that your answer? Fashion? What was the link to google all about then? Whats your explanation? Levity, wasted. However anodised snail cams defiantly make your suspension work better. (thats a joke, again) 4 minutes ago, faussy said: FWIW, Danillo Gallizi has a forward facing brake arm, he's probably just a slave to fashion. Danielle's bike is interesting, with footrests moved forward, and a garelli back box. Why do you imagine all the works bikes (that I've seen) have this mod ? I have bikes with backward facing brake arm, forward facing arm, and fantic 300 brake plate. Hard to do a scientific test as they are all used and have different brake linings and brake cables. But in my examples the best is the fantic, followed with forward facing and last rear facing. Quote Link to comment Share on other sites More sharing options...
b40rt Posted February 18, 2020 Report Share Posted February 18, 2020 Quote Link to comment Share on other sites More sharing options...
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