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The TW is the first bike I've owned with drum brakes on the front wheel. I've noticed braking seems 'softer' than with a disc brake, but I may need new springs (there is still 1/8" pad left). Braking isn't bad, it's just different. I do like the fact I don't have to mess with hydraulics and associated issues with fluid levels, air bubbles, etc. But if I buy another TW for strictly off-road use, I may look at buying a newer model and wondered about the difference.

So my question to those who ride off-road and have experienced both disc brakes and drum brakes:
Is there a real performance difference between the two (or is it just a weird perception of different handling on my part?) Are disc brakes preferable off-road, or do drum brakes have an advantage?
 

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I've got an older and a newer TW. To me the main difference is just feel. I do notice that the drum front brake does fade a little with hard stops from 55mph. Off road I don't have a preference.
The disc brake is easier to work on with the parts being external, no pulling the wheel off to work on it.
 

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Haven't tried both of them, but my 87 stops just fine with drum brakes on any surface. This has been addressed many times on the forum. The general opinion is that they are about the same.
 

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Let me ask you this;
Is the braking fairly even between front and rear brake? Do you find the rear brake to be good? I have the disc front brake and all TW's have drum rear brakes. I find the rear brake darn near useless compared to the stopping power of the front brake. In order to get the rear to do anything close to the front brake, I really have to press on it. The front brake is a two-finger operation with the precision of a surgeon's scalpel compared to the rear's clumsiness of dragging a rock to try and slow down.
 

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The real difference between drum and disk only occurs in two scenarios: One, if you are riding down a very steep and very long dirt track (like two + miles) using 99% front brake there is a tendency for the drum to fade. Most of us will never encounter this in our entire riding experience. The other is when you go through a river above the axle and get the brakes thoroughly soaked. It will take a few applications of drum brakes to dry them out enough to work well. Again, only people like Admiral like to use their TW's as submarines. :p

The disc does have more ultimate stopping power than the drum but few of us will ever need it. Both of them are capable of locking the front wheel, which most of us don't try twice.:eek:

Ski Pro: Have you checked your rear shoes for glazing or other issues? My rear brake will lock the rear wheel at any speed on any surface.
 

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Fine mud, the soupy stuff, will play havoc with a drum brake.
Just remember that the old 500cc 2 strokes use to have them.
 

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The drum brake is cable operated — this means it will feel slightly spongy due to the cable, but the bonus is, it will work in the rain (first time)

The disc brake is hydraulic — this means it (should) have a harder feel to it — but as the working parts are exposed to the elements, it may take some persuading to stop in in a downpour.

In a water crossing situation, both will suffer from ingress of water — “feather” to dry off as above.

In ‘yer modern bike — twin disc four pot fronts will pretty much stop you underwater — and twin leading shoe drums will stop on a sixpence - but this bikes design is 30 years old — treat it as such.

I’ve had bikes with in-board discs (great, but prone to fade) — cable operated discs (utterly useless) — you name it, I’ve tried it. Just ride accordingly, (and never underestimate the combination of the rear brake and the power of engine braking on these little thumpers, which used together with a TW34 will seriously test your front suspension) ……. ;)
 

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It appears that you all have covered everything in reference to the two breaks I have a question on servicing the front disk break. I have 9000 miles on my TW should I change the break fluid and is there any other service required?
 

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to quote Lizrdbrth:

Disc front wheels have thicker spokes and the spoke lengths and lacing pattern is different from a drum. Same spoke count. As far as I'm concerned both are equal in terms of actual braking distances. It's more a matter of "feel" than effectiveness. Pick yer poison here. Drums don't bother me at all. I own both.

The rear brakes are all the same. They blow.


i was going to swap disc for drum on my '94 but russ convinced me it wasn't worth it.

http://tw200forum.com/forum/general-discussion/7892-older-newer-whats-difference-2.html
 

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It appears that you all have covered everything in reference to the two breaks I have a question on servicing the front disk break. I have 9000 miles on my TW should I change the break fluid and is there any other service required?
Most people only change the fluid when it gets “soft” – but given the amount of fluid in there is “negligible” it wouldn’t hurt to do it every 5 or even 10k. It’s like changing your tires with age, everyone will have their own preferences.

But while we consider that fluid change is a simple enough job – how many here even know how to service the calliper or can recognise when the disc is past its best ?

Just like a drum brake, all sorts of “crud” can get in the nooks and crannies, and eventually affect the pad wear. If you take the calliper in one hand and look closely, you will see that it really only has one moving part – the piston. You should be able to push this back in by hand (using both thumbs). If this is the case, then it’s fine – if not, then you need to think about the replacing the seals and polishing the contact surfaces.

There should be either one or two rubber seals that fit onto the piston, and they fit into grooves on the piston to act as “moving oil seals” as the fluid behind them is pressurised by the brake lever. As you can imagine, if they are “catching” on the calliper, then the piston won’t move back properly, resulting in undue wear on the pads and the disc. If the piston seems stuck, you can often “pump” out the piston using the brake lever until it simply pops out into your hand. A word of warning at this point, brake fluid makes excellent paint stripper so wear gloves.

With the piston out, clean up the piston and replace the seals (cheap as chips), and put it to one side. Now comes the tricky part. Envision if you will the part of the calliper housing that the seals come into contact with – this surface needs to be squeaky clean or it will ruin your new seals. Take extreme care when cleaning these surfaces, you only need to “polish” it, not wear it down (at all). When you’re happy with the result simply gently push the piston back into place, taking care not to “worry” the new rubber seals on the way back in. There will be a fair bit of air now behind the piston, that simply needs to be pumped out using the bleed nipple as normal. When you’ve done all that, check to see that it’s moving freely by using the “two thumbs” method above (be careful not to pump the piston all the way back out when trying this).

If your piston moves back freely, you can skip the above step, and go for “routine maintenance” as follows. (This can all be done with the calliper still bolted to the forks).

Take the pads out completely, and if it has a “bit of spring steel plate behind it” – remove this also (make a note of how it goes back in). You won’t need to remove the dust seal on the piston this time as this is as deep as were going to go. That piece of “spring steel plate” is called the “anti-clatter plate”, and it needs to be cleaned off without “flattening” it. As the name suggests, its purpose is to take up the slack between the pad and the piston, the shape of it is what makes it work, that and the fact that it’s made of spring steel. Just brush it off with a wire brush, and that’s taken care of. Now take a look at the pin called a “retaining bolt” in the manual. Brush it down just like the clatter plates – the object of the exercise is to remove any build-up of dust and corrosion that will affect the pads from sliding freely. Re-assemble the parts, and you’re done. DO NOT use grease on anything to do with this procedure – it will melt with heat, get everywhere, and your brake will become useless.

The disc : Discs are a “consumable” part, simply because they can and do wear out. With all parts in place, rotate the wheel and feel the disc between your fingers. Any side to side variation and the disc is warped – replace. You can sometimes feel this warp as “judder” when braking.

Check the thickness – it should be - Min. brake disc thickness Standard:3.5mm (0.14 in) Limit:3.0 mm (0.12 in). Don’t forget this is measured where the pads come into contact – if you can feel a ridge on the outside of the disc, the wear has started, though it may not yet be “terminal”. The only way to measure this is by using a micrometre in the center of the disc surface. If you allow it to fall below recommended levels, this can lead to “warp” occurring. Start taking this issue seriously at around the 10k mark.


When “playing” with your disc brake or calliper – always use a torque wrench. It’s no fun when they fail you ……

Edited to add: By “the piston moving back freely”, I mean that it will move back, but slowly due to the thickness of the fluid and the small passages in there. So – (generally speaking) - “If it moves” it’s fine …..
 

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I personally change the front brake fluid annually as a normal service on my bikes. Brake fluid absorbs water and will corrode the inner components over time. It's just one of those things I do once a year before riding season starts.

If you really want to make the brakes better in the front get the braided brake line that pro cycle sells. I have it on both of mine and the lever is much firmer and they feel stronger as well.

My Ducati will literally boil the rear fluid because the master is so close to the exhaust pipe. If I dont change that one it becomes a sponge with zero power.

On cars I do a full flush any time do pads which works out to be every other year for me.


Sent from my iPad using Tapatalk
 

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Just wheelie through all the mud and puddles. They will keep both the drum and the disc dry.
 

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The disc does have more ultimate stopping power than the drum but few of us will ever need it. Both of them are capable of locking the front wheel, which most of us don't try twice.:eek:
Its precisely a year ago that I locked up my front wheel while doing about 30 mph(my front brake is a drum), came down hard on the tarmac, since then I'm ever so gently pulling that lever every time I want to stop. . . .
 

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:hello: Oh...Oh...Oh... I know the answer to that one....pick me :hello: pick me :wave: pick me :hello:
OK then “smug one”

How many of us ?

(and I want an exact answer, which I will then check with the rest of the class) :p
 

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Very nicely written brother Purple... just sayin. ;)

Most people only change the fluid when it gets “soft” – but given the amount of fluid in there is “negligible” it wouldn’t hurt to do it every 5 or even 10k. It’s like changing your tires with age, everyone will have their own preferences.

But while we consider that fluid change is a simple enough job – how many here even know how to service the calliper or can recognise when the disc is past its best ?

Just like a drum brake, all sorts of “crud” can get in the nooks and crannies, and eventually affect the pad wear. If you take the calliper in one hand and look closely, you will see that it really only has one moving part – the piston. You should be able to push this back in by hand (using both thumbs). If this is the case, then it’s fine – if not, then you need to think about the replacing the seals and polishing the contact surfaces.

There should be either one or two rubber seals that fit onto the piston, and they fit into grooves on the piston to act as “moving oil seals” as the fluid behind them is pressurised by the brake lever. As you can imagine, if they are “catching” on the calliper, then the piston won’t move back properly, resulting in undue wear on the pads and the disc. If the piston seems stuck, you can often “pump” out the piston using the brake lever until it simply pops out into your hand. A word of warning at this point, brake fluid makes excellent paint stripper so wear gloves.

With the piston out, clean up the piston and replace the seals (cheap as chips), and put it to one side. Now comes the tricky part. Envision if you will the part of the calliper housing that the seals come into contact with – this surface needs to be squeaky clean or it will ruin your new seals. Take extreme care when cleaning these surfaces, you only need to “polish” it, not wear it down (at all). When you’re happy with the result simply gently push the piston back into place, taking care not to “worry” the new rubber seals on the way back in. There will be a fair bit of air now behind the piston, that simply needs to be pumped out using the bleed nipple as normal. When you’ve done all that, check to see that it’s moving freely by using the “two thumbs” method above (be careful not to pump the piston all the way back out when trying this).

If your piston moves back freely, you can skip the above step, and go for “routine maintenance” as follows. (This can all be done with the calliper still bolted to the forks).

Take the pads out completely, and if it has a “bit of spring steel plate behind it” – remove this also (make a note of how it goes back in). You won’t need to remove the dust seal on the piston this time as this is as deep as were going to go. That piece of “spring steel plate” is called the “anti-clatter plate”, and it needs to be cleaned off without “flattening” it. As the name suggests, its purpose is to take up the slack between the pad and the piston, the shape of it is what makes it work, that and the fact that it’s made of spring steel. Just brush it off with a wire brush, and that’s taken care of. Now take a look at the pin called a “retaining bolt” in the manual. Brush it down just like the clatter plates – the object of the exercise is to remove any build-up of dust and corrosion that will affect the pads from sliding freely. Re-assemble the parts, and you’re done. DO NOT use grease on anything to do with this procedure – it will melt with heat, get everywhere, and your brake will become useless.

The disc : Discs are a “consumable” part, simply because they can and do wear out. With all parts in place, rotate the wheel and feel the disc between your fingers. Any side to side variation and the disc is warped – replace. You can sometimes feel this warp as “judder” when braking.

Check the thickness – it should be - Min. brake disc thickness Standard:3.5mm (0.14 in) Limit:3.0 mm (0.12 in). Don’t forget this is measured where the pads come into contact – if you can feel a ridge on the outside of the disc, the wear has started, though it may not yet be “terminal”. The only way to measure this is by using a micrometre in the center of the disc surface. If you allow it to fall below recommended levels, this can lead to “warp” occurring. Start taking this issue seriously at around the 10k mark.


When “playing” with your disc brake or calliper – always use a torque wrench. It’s no fun when they fail you ……

Edited to add: By “the piston moving back freely”, I mean that it will move back, but slowly due to the thickness of the fluid and the small passages in there. So – (generally speaking) - “If it moves” it’s fine …..
 

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Having owned one T W with drum brakes and 2 with discs, I can say either one is acceptable in nearly all riding conditions.
The T dub is not fast enough to fade a drum unless you are using brake and throttle at the same time down hill.
However the rear brake on my first one wore down so that the actuating cam would go over center and the brake would lock up the back tire and not release it untill I used my hand to reset the lever. New shoes was only a temporary fix. The hub had worn to such diameter that The new shoes didn't have to wear much before it would happen again.
It had more than twenty thousand miles on that hub, rough hard mountain miles.
 

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....As a general rule of thumb, if someone told me they had 9,000 miles on a TW200, I would say it is time to replace the front brake fluid.
Yeah, I did mine at five years/10,000 miles. The fluid was still relatively clean and brake still worked perfectly. But I live in a real dry climate and the bike is stored indoors.....YMMV. In a real wet climate I'd say 3 years or 5,000 miles.
 
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