Another drum query

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Cast iron disk(s) are better in the wet than a wet drum brake.

Or if its JUST looks we're discussing.
I must be getting old - I prefer the looks of a good disk brake setup over a weak ole drum any day....
 
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I'm firmly of the belief that on any motorcycle, function must come before appearance. Appearance is also important, but not at the cost of function. That's why I have never understood the custom bike scene, which is completely the other way around, appearance before function, frequently appearance instead of function.
Anyway, Acebars all the best with the project.
cheers
wakeup
 
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I sort of don't understand the argument here. I think it's obvious that a disc brake is superior to a drum brake in nearly every way other than perhaps appearance. And even the point of appearance is a matter of preference.
But in this case, we're talking about a guy that's putting together a road bike and looking for a decent drum brake for a fair price. Certainly lots of old Nortons came with drum brakes and they performed adequately when used. The Commando 2LS drum brake has been used extensively, and certainly will perform better with the available stiffening kit. If we're talking about a drum brake for a Norton, I'd say the Commando 2LS is most appropriate in this case. Will it stop as well as a disc? Will it fade faster than a disc? I think those answers are obvious to anyone that's far enough along to be wrenching a bike together.

Loads of guys race, around the globe with era appropriate drum brakes, and some of them have good success in doing so. Certainly a disc would be better, but on a normal man's road going Norton, a drum brake would be quite fine in my opinion. Certainly one should be aware of the stopping power and all other functions of the bike, but I'm quite certain you can have a really good time riding an old Norton on the road with a drum brake. Sure seems like plenty of them are out there doing so.

If all we're talking about is function over appearance, than we might as well sell all this old crap and buy brand new BMW's with triple disc brakes, traction control and ABS.
 
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wilkey113 said:
I sort of don't understand the argument here..........If all we're talking about is function over appearance, than we might as well sell all this old crap and buy brand new BMW's with triple disc brakes, traction control and ABS.
As far as I understand it, Acebars is building what used to be called a "special" for his own road going use, a little bit of gentle cruising, with a certain style. He asked the question about a suitable front brake. It's not about originality, or (wilkey113 words, not mine) old crap, its about having a bit of fun, in his own way. As such, in my opinion and for what that's worth, function is most important, and if it was my project I would use a good disc brake......but that's just me. If Acebars wants to use a broomstick, stuck in the spokes, its his choice. As long as he is aware of the options he can do what he wants within legal boundaries etc.

It's not an argument, its a discussion.
cheers
wakeup
 
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Must say I completely agree with wilkey113

If all we're talking about is function over appearance, than we might as well sell all this old crap and buy brand new BMW's with triple disc brakes, traction control and ABS.
Didn't want to create an argument or a storm, I have more than enough info now to make an educated choice so thanks everyone really appreciate the advice all around.
 
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I think a lot depends on what the bike actually is. I must confess that if I owned an early commando and the standard brake was a drum, I would only change it if I was going to race the bike, or turn it into a cafe racer. It is very easy to improve an old machine by adding modern parts however the definition of quality is 'fit for purpose with obvious attention to detail', and that is why I hate seeing Japanese levers, clocks etc on British bikes. There is nothing nicer than seeing an old bike which is nut and bolt perfect. Authenticity is valuable.
 
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wakeup said:
Triton Thrasher .... The bike was pretty heavily loaded, the hill was very long, and I was cruising down, initially braking gently, just trying to maintain a reasonable (slowish) speed. The hill was too long, the bike was too heavy, the brake got too hot. In retrospect, had I known the road, I would have been in second gear with my speed down to a fast walking pace far earlier. However I didn't know the road, so I had no idea how long the downhill bit was, or that there was a "T" junction
In general use it was an excellent brake, very controllable and quite powerful.
wakeup

Thanks. Yeah, on long hills, I do very little braking, whatever vehicle I'm using. Glad you got off with it.
 
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Acebars said:
P.S. Pudding basin helmets are really great around town, so easy to pop on and off! 40mph max though imo! :D

Conversely, even the best modern helmets do most good (save lives) in low speed accidents. Nothing can save you if your head hits a wall at speed.
 
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wakeup said:
Bernhard....With the exception of the different linings the front brake was as you described, it was set up by Joe Dunphy (as I remember) who at the time had a service doing exactly what you described. It was a good brake, very powerful and smooth, but it would fade. It would pull up beautifully from 90mph....once, then it needed a couple of minutes to cool down.
Triton Thrasher .... The bike was pretty heavily loaded, the hill was very long, and I was cruising down, initially braking gently, just trying to maintain a reasonable (slowish) speed. The hill was too long, the bike was too heavy, the brake got too hot. In retrospect, had I known the road, I would have been in second gear with my speed down to a fast walking pace far earlier. However I didn't know the road, so I had no idea how long the downhill bit was, or that there was a "T" junction
In general use it was an excellent brake, very controllable and quite powerful. With the bike loaded, downhill, the brake simply could not dissipate the heat. My point was that sometimes the road rider can encounter situations that the racer does not. For that reason I would suggest a decent disc brake.
cheers
wakeup
can I ask was it the Single leading shoe, or 2ls, with air scoop :?:
 
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acotrel said:
Wakeup, you are so correct. I don't know what the discussion is about on this topic, some people just will not be told !
Riding a motorcycle is extremely dangerous if you cannot grab a handful of front brake with impunity. Disc brakes have no self-servo and they are much safer than any drum brake, even if the master cylinder ratio is wrong. The dual discs on my Seeley 850 only require the same light touch that my 7R AJS used to require for strong braking , however the difference in safety is extreme. My only really damaging crash in road racing came when I was a bit out of practice, and put only the slightest amount too much pressure on the drum brake to avoid hitting another idiot. Seriously, it was actually a 'near death experience ', and not something I can ever laugh about. The bloke that caused that incident is still around and he stays well away from me when I'm on a motorcycle. When you destroy a helmet that is very serious, and I haven't forgotten.
I think there is a tendency to look at old motorcycle road racing footage with a level of scorn, however a lot of bloody good riders were killed in the old days through machines, equipment and circuits which were simply unsafe - the risks had not been minimized to a tolerable level. There is a thing that happens in car racing in Australia. Some guys race cars from the thirties and a couple of them have simply fallen over. One killed the driver. I suggest it is a matter of priorities - should we try to recreate the past by using something simply because it looks good, and kill people in the process ? Some of that old crap should simply be in museums.
Re; “Disc brakes have no self-servo and they are much safer than any drum brake”
This is true on your opposed pistons Lockheed brake, but fir a 4 pot caliper and there will be a free servo, or half that with a 2 piston fitted on a slider.
 
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Healthy discussion here, and I think it's a good one. Brakes are important, and there are a lot of options and opinions.

Just to clarify here, my comment about "old crap" was a comment of sarcasm. I love this old crap. To me, it's beautiful and valuable, and I like the 1960's riding experience. So a drum brake on a 1960's or early 1970's Norton, in my opinion, is appropriate.

I've built a couple of "specials" during my time with Nortons, and I've used drum and disc set ups. Simply a matter of opinion when it comes to what you're trying to achieve. I just think that in this case, the question that started this thread was about some different drum brake options, and no mention of a disc brake at all. Acebars listed the drum brakes that he was considering for his build and was asking for opinions and input based on other's experience with those options. I think it's logical, when talking about brakes, that disc brakes would be mentioned as part of the discussion. But Acebars made it clear, several times, that he wants a drum, and that he'll be riding it on the road, and not racing.

So, in my experience, the Commando 2LS brake would be the best option. This is based on having adequate stopping power, keeping the drum brake, appearance and just all around being appropriate for a Norton. I'd of course re-line the drum surface, install new brake pads and fit the stiffening kit for best results. Past that, I think you'd have a great brake with plenty of stopping power considering your application and preference.

Any of the other 2LS options that were mentioned might take some fettling to get them to fit and work properly. Certainly not impossible to do so, but definitely not a straight not up application either. In regards to 4LS options, they obviously start to get pricey, and as Acebars mentioned, he didn't want to spend the money for the high dollar exotic replica brakes. Which I totally understand. So, for the sake of a 4LS conversation, you basically have the option of the Suzuki 4LS and the Grimeca. Both are semi reasonably affordable. In my opinion, I think the Grimeca looks odd. The die cast look just seems cheap to me. I've never ridden a bike with one, and I would assume the preform well, I just simply don't like them. As for the Suzuki, well, it's just too Japanese for me. Many will say that it's heavy, and that may be true. I just don't really like how it looks and don't like the fact that it's a Japanese brake on a British bike. Again, this is simply my opinion.

Acebars, best of luck with you special. Please keep us all posted as to what you end up going with, and how it performs. Always good to get feedback from someone that uses a specific brake / set up, and what they think of it.
 
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If your drum brake doesn't work too well, you can always drag your foot on the road. That might work even better. A friend of mine bought himself a T250 Suzuki, and because he was used to riding push bikes was averse to using the front brake. He went through a pedestrian crossing full of people, leaning back and holding onto the handle bars like grim death while both of his feet were skidding along on the bitumen.
 
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Bernhard said:
can I ask was it the Single leading shoe, or 2ls, with air scoop :?:
'course you can Bernhard, it was the 8" SLS, but it did have an airscoop, and air exit holes, installed by the previous owner. As I've said it was an excellent brake, just so long as it didn't get hot. Then it became ballast.

The best of luck to Acebars, lets see some 'photos when it's complete

cheers
wakeup
 
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I'm not being picky Matt, but all of those brake plates have an "air in" hole, but none of them has an "air out" hole. The end result being that there is no airflow, however turbulent through the brake, so that the brake just relies on its external surfaces to unload the heat.
Having said that, they are speccy looking brakes though.
cheers
wakeup
 
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wakeup said:
I'm not being picky Matt, but all of those brake plates have an "air in" hole, but none of them has an "air out" hole. The end result being that there is no airflow, however turbulent through the brake, so that the brake just relies on its external surfaces to unload the heat.
Having said that, they are speccy looking brakes though.
cheers
wakeup

Looks to me like the Tickle brake has an "out" scoop, at 7 o'clock.

The side-facing holes in the 4LS aren't particularly "in" or "out," are they? But they're big holes and I'd expect many air changes per minute at speed.

Having said all that, I've little faith in sporty scoops and holes in drum brakes for effective cooling. And they let the rain in.
 
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If you look closely at the centre finning on the gold coloured hub you will see exit slots for the air, this is not uncommon on 4LS brakes.
 
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Triton Thrasher said:
Looks to me like the Tickle brake has an "out" scoop, at 7 o'clock.

The side-facing holes in the 4LS aren't particularly "in" or "out," are they? But they're big holes and I'd expect many air changes per minute at speed.

Having said all that, I've little faith in sporty scoops and holes in drum brakes for effective cooling. And they let the rain in.
Triton Thrasher
I can't see an "out" scoop, looks to me to be the outer cable stop.

How would the air change in the rather speccy 4LS. The inside of the brake would arrive at a balanced air pressure (which could be anything, positive or negative) and then just get hotter

A well designed air inlet scoop and an appropriate exit can work well, but "well" only within a certain speed range. To get right can take a lot of fiddling about and trial and error. Even then they are something of a compromise, and yes they do let the rain in (plus insects, stones, grit, small furry animals etc)

dave M said ...." If you look closely at the centre finning on the gold coloured hub you will see exit slots for the air, this is not uncommon on 4LS brakes."

Are they cast in or machined? Casting them would require some special techniques, which probably explains the cost!!

cheers
wakeup
 
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The John Tickle brake plate definitely has an exit scoop at about 7 oclock. I've got one here, and with the front scoop and it's fine mesh screen, coupled with the rear vent, I'd consider it to be well ventilated considering the era it was made.
Not sure hoe many guys are riding around on vintage machines in the rain, but other than fine dirt, I'd say it's safely protected. I'd of course pull it off every now and then and give it a proper cleaning internally.
I'd also add that it's quite well built, and the components are very nice. The casting is far more substantial than the Commando 2LS brake, making it much more beefed up and solid inside.
I'm perhaps a bit biased as I really like these old aftermarket bits, but in my opinion, it's a nice bit of kit for a 1960's era Norton special.
 
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