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[stinkwheel]

It was definately a problem with drum brakes "back in the day".


You'll notice an air scoop fitted to the front drum on many old Brit bikes. Not at all uncommon for people to drill holes in the brake-plate to allow for better air circulation too.


"Bacon slicer" discs fitted round the outside of the drums were also popular at one point.


The only really useful suggestion in addition to those already given is to leave a bigger gap or go slower.


Actually, that's npot necessarily true. I fitted a span-adjustable, upside-down clutch lever off a late model GPZ500 to my Jawa as a front brake lever (you can even use the clutch idiot switch as a brake light switch) . It made an enormous difference to the braking effectiveness, presumably due to the cantilever action of the lever and the fact it is sat on a bushing.


Regarding hydraulic Japanese disc brakes fading, it is entirely possible to boil them into oblivion if you try hard enough. I have done several times, leaves you with no brakes at all. You just have to stop and wait for them to cool down.


If you want truly apalling brakes, try riding something with the abortion that was the cable operated disc brake, as fitted to the early CB125 twins and the CD200. It doesn't work, right up to the point where it starts binding.

[Riggers]

Around 1974 I had a BSA Rocket Three with a single sided conical ('comical') hub with TLS front brake. In their wisdom BSA fitted the same brake to all their models from 250 to 750. I reckon on a 250 it might have been s decent brake but on a 600lbs 750 it was utterly, utterly useless! Once I shot past my mate on a Bonneville as we approached a round-a-bout with the brake full on - I just couldn't stop. He thought I'd just become a real fast guy - I never put him right!!.


 Wish I had the bike now though. I reckon it would be worth around £10 grand, and to think I flogged it for 400 squid!


Tony R.

[Gwilly]

Yes riggers i,m in sympathy with you there. Think it was 1973 i flogged my old 59 Norton dominator 99 600 to a mate for £60.00 because the insurance premium for some reason had risen to £36,00. Think all insurance went up that year but cant remember why. Be worth two grand in boxes now. Makes you weep donnit.

[Alan R]

Hi Gwilli-------- glad to see that Gorilla Grip didn't turn into a Gorilla Dump !! . Old Bikers ( and their linings ) don't die ,  they just ------ F--A---d-------e         away !!

[Riggers]

Well Gwilly we can all go out and cry in our beer on Friday!


Reason why I got into this thread is because I'm just in process of fitting new shoes to my 2001 500 Classic. I've never found the TLS brake on this bike to be much good despite tweeking this and that.


So today I've bitten the Bullet and ordered some new high grip shoes from our hosts together with a heavy duty cable as per Paul M H on this thread.


Job won't be finished until next week but I'll post on here the results. Fingers crossed I'm hoping to be able to actually stop next time some duffer pulls out in front of me instead of heading for the grass.


Cheers


Tony R.

[simon]

My no brake moment was with twin front disks on my old Ducati 860. I was on a big ride around 600 miles and had come through a massive downpour. The disks on the duc have no holes in so are badly affected by too much wetness. Not then knowing this I applyied them in the usual fashion in response to the car in front applying his brakes and finding the usually excellent and progressive Brembo's had totally disappeared I in panic adopted  a sudden and over zealous use of the rear brake with the result of a sphincter clenching tail end slide. The bloke I was riding with gave me the strangest look but it stopped me from following too close for the rest of the journey. 

[stinkwheel]

Simon. One interesting thing about disc brakes of which you may not be aware is that the holes in brake discs don't really make much difference to the barking ability in the wet. They are almost entirely for ventilation. The actually impede braking efficiency by reducing the friction area but balance this by dissipating heat better and reducing unsprung weight.


For performance in the wet, it's almost entirely down to pad material. Sintered brake pads are not affected by water on the disc (which is the main reason I fit them).


Not sure how long ago the incident you are referring to happened but if you still have the bike, fitting sintered pads will prevent recurrance of this problem.


 


While we're on the subject of braking anecdotes. I once had to stop a suzuki T500 which was doing 80mph with the throttle stuck wide-open. The ignition key is not reachable from the riding position and there is no kill switch. Remarkably, the TLS drum managed to stall it out before I went into the field although I'll admit I was getting ready to bale-out. Pulling the clutch in and allowing the engine to blow did occurr to me but only breifly. It did have re-lined brake shoes fitted with ferrodo friction material.

[simon]

I have replaced the pads since but have avoided big wet rides so haven't seen if the wet weather braking is any better. The other nasty moment on the same marque and model but different machine was in Sydney Australia in the 80's when I put Armorall a liquid silicone polish on the seat. Riding with my then girlfriend (now wife) on the freeway up to the Blue Mountains I decided to give it some stick only to discover that the seat wouldn't hold us and we were both slipping off the back of the bike. Of course as you slide back the ability to throttle off is removed and with Susan screaming that I was trying to kill her in my ear it seemed ages before I worked out that applying the foot brake was the solution. That was only the first of a couple of disasters that day ( I mistakenly left her at a petrol station later that day) so it is remarkable that thirty something years later we are still together!

[Alan R]

Hi guys----- have a look at Wikipedia Disc Brakes-----quite a comprehensive and informative read. I remember one "Urban myth" that said ---- Drum brake fade was because the hot drum expanded faster than the shoe assy. could do!!   No, as several of you have stated it's the point at which the friction material cannot dissipate the generated heat fast enough and starts to loose it's performance characteristics. So,  based on that definition a disc brake potentially can fade-----especially if cheapo pads cannot cope. Added to that scenario is the close proximity of the hydraulic fluid to the pads----so if your fluid has absorbed some water (Hydroscopic)-----(and it will gravitate to the lower parts, being heavier than the hydraulic oil ) then that will start to boil inside the pipeline. Change your fluid regularly---go to DoT4 if that's ok to do. Sintered pads (little flecks of copper or bronze within the pad material) are probally the better all-round compared to organic  which are more suited to dry conditions but wear out quicker. Have a look at  ----------  www.pinkbike.com ------------- it's for cycling but the underlying priciples still apply. I tend to use EBC sintered pads when I can. Tried a green, organic set on my Triumph tripple coming off Dartmoor hills a while ago 2-up + bags----VERY impresive but mediocre in the wet going up the M5. There is a guy who has a 6-leading shoe, 7" full drum on a BSA Gold Star --- what a stopper !!!

[stinkwheel]

The TLS drum on my Dads Kawasaki KH350 is super effective. You could do rolling stoppies on it (if you trusted the bendy fork stanchions).


It is a very big drum though. The spokes are about 1" long.


(Yes I did mean 350, it is rare and unusual and the brake is about double the size of the one fitted to the early 250 models) .


I used to use EBC sintered pads but I've found that Armstrong ones are both cheaper and better.


I had a go of a mates Z1100 which has a single pot pivoting calliper and one of those chromed solid discs. Contrary to expectations, it nearly folded itself in half when you applied the front brake. Turns out his secret was fitting it with Brembo sintered brake pads. They were truly awesome and I could almost justify paying three times as much as EBC ones to get brakes like that.