can you lock up your rear drum brake

just went for a spin around the block after the bike has sat for years....gettin her back in shape. went to hit the brakes and it felt mushy but...it's been so long since I rode my 70 commando, I forgot if I used to be able to lock it up or not? can you guys lock up your rear drum if needed? thanks.

Not from any speed.
And some of these newer stickier rear compound tires may make it more difficult, but from low speeds usually yes.
Unless the surface on the road is fresh new big sharp stones type stuff..

How long since you looked at it. ?
If the brake surface in the drum has acquired a good coat of rust, you probably have rust-dust to rust-dust contact, and dust embedded in the brake material, so friction qualities may be minimal. A good deglazing of the shoes and a cleaning of the brake surface often helps. !

Also, if the friction material has worn down and your little brake lever on the rear drum is much past the 90 degree mark, static, then braking qualities may not be too good.
Hopethishelps.

Why Yes I have in 2 Combats but, Ugh, not lately no matter following all the years of advice which will be repeated again and again. There's a couple neat things you can do if ya can lock up rear brake, pull to a stop while sliding skewed to direction of travel the fork is pointing and to flip back up out of a low side crash. Otherwise the Norton non lock up brake is a safety feature a kin to ABS. This brings up a deep mystery to me as when I got Trixie my 2nd Combat she'd sat up years in gulf coast area shop so very surprised by what happens with lock up rear ability on pavement up to about 40 mph! Brake decayed to normal so so slowing after deer strike and went through everything but the engine, so extra sanding clean and true on drum and shoe contacts, well adjusted cable etc but no matter how hard i stomp or stand on rear brake now it can barely scratch Gravel. My first experience on lockable rear was my Peel when rear sets put on wrong way > so there was direct straight cable line to the drum lever, but even so not as easy lockable as Trixie. Strange strange strange and I've learned nothing to correct or improved futher but live with it. Maybe rusted drum and some caked grease is the key, just like it is on grabby clutch plates. I can assure though that anything that is more oil like on pad makes the brake about useless. Its one of my mechanical manhood crusher failures on Commando-doom. I do know what I'm missing out in this area.

Not if my life depended on it.

The HEEL of the boot on the peadal will , but ONLY at 5 mph .

Some moron I knew used to stomp his Daytonas brake pedal , and drag his steel heels on the highway at night .

Some moron emulated this . The 650s a bit weightyer . Theres a bang and grauching ,
as the anchor stay snaps & it winds the brake actuateing rod around the spinning drum .

Oops .

So , ONLY at FIVE mph , and tenderly . Used to flick into neutral and if heavy traffic , stomp the pedal at 2 or 3 mph .
Decent linings & maintanance ( blow out dust , emery paper shoe & drum to remove glaze , say every 5 - 10 .000 miles .

Some decent pads for the front wouldnt be a bad idea either .

I never use the rear brake unless I'm really desperate and I'm doing a crash stop, or if the bike is really out of shape I sometimes use a little bit of it to regain control. A smooth downshift is usually a better option. Locking the back brake is often the quickest way to end up on the deck, particularly if your tyres are hard (cold ? ). ( One of the advantages of a CR box over the standard one. )

Not if your life depended on it Swooshdave?? Well like me, you are ridding with rearsets so our peddals are short giving little leverage. The convoluted travel of the cable doesn't help much too. Been wanting to turn mine or just send it to Vintage brake for the full service witch I hear works wonders...

Alan, about every other motorcycle ever sold have decent enough front brake the rear brake is about useless for normal slowing on firm dry surfaces as the front can grip-brake enough to lighten the rear so its got nil or no effection traction, except for the factory Lockheed Norton Commando disc brake. Get on a slope of wet grass or very dry loose gravel and front grip even with poor Norton set up begins to lock front so have to add rear to slow down or prevent speeding up. In normal factory optimal front brake its got a resistor 'valve' in the master cycling that a red hot nail can open up then must be a bit careful not to lock front going 60+ on great traction surface and new tire. So much so I'm never ever going back to a 100 size front as so dam restrictive to slow up in time howling and squealing compared to a 110. If yoose guys are not complaining of too much front brake for 100 tire then ya don't know what ya missing out on sticking with factory kit.

So far I'm the only one reporting a fairly easy lock up on 2 rear brakes [in past] with factory kit leaving black stripes anytime i cared too or often enough when I did not intend too, they were that effective. Yet for the life of me I can not get decent rear brake again -even on the loose Gravel must stand on it to lock up and then only going below 15 mph, sheeze. I"m considering drilling holes in the drum friction surface to maybe get more edge encountering grip. May try pickling the drum surface for a type of tough rust oxidation layer - which I think may of been the key factor in long set up Trixie with a much better rear brake than even my most loved performer Ms Peeel that could out front brake moderns d/t too moderns excessive tendency to stoppie if not letting off some. I ran into this almost crashing a few time hopping off my SV650 dual 320 front brake on pure gum balling non DOT race tire, it'd stoppie before reaching the mere communing pull downs i did on Peel. Point being there is a potential to get a great rear brake, but the way to do so escapes me and apparently everyone else so far. i have sanded the drum shoes watching the witness contact to get nice even all around contact so if ya think Brit Brakes refinement fittment is the key - ha wait till you try it after the time and expense and get back to us please.

Yep, on occasion...awhile back it was when an idjit ran a stop sign, I hit both brakes hard and did stop in time, barely

Ugh, My 1st Norton panic brake need was on P11 drums so freaked out locked both tires which caused rear to swing out till bike got sideways on both tires and frame rail to actually stop shorter-just enough before injury/damage. Hope never to have that occur again in public. If not laying it down fully sideways it would tend to hi side ya into what ever. This is one reason Peel has crash cage to slide on fully sideways on two locked tires, practicing crashing on pasture grass then THE Gravel then pavement, till I get the hang of it or not.

Hm maybe besides holes in drum surface might also help to drill some holes in the shoes too. With foot/body force on brake lever there should be enough mechanical shoe pressure, so my sense is the friction material is somehow a poor gripper on smooth steel. Hm may take my dremel tool to the drum surface to cross hatch it some as sure ain't got much to loose. On Trixie I use both brakes when really need to slow up fastest as the 100 front just can't grip enough to lift rear out of effect. Often enough on I'm on max front tire noise braking and vary the slow down security by adding in more or less rear brake. If I can't force myself to scare myself on panic level brake practice that almost looses it on skip out Squeeches then I know I'm not fit to play fast road games that outing so don't.

david7212 said:

can you guys lock up your rear drum if needed? thanks.

Click to expand...

Yes I can! At any speed, in any contition and with an expected (normal) amount of pressure. I Use the RGM High friction shoes and keep the assembly clean.

I weigh 2 and a 1/4, have Avon Roadtriders, and rearsets.

gtsun said:

Not if your life depended on it Swooshdave?? Well like me, you are ridding with rearsets so our peddals are short giving little leverage. The convoluted travel of the cable doesn't help much too. Been wanting to turn mine or just send it to Vintage brake for the full service witch I hear works wonders...

Click to expand...

I can attest to the great brake after Vintage Brake performs their work.

I have modified my rear brake so that I can not lock it up. Maybe if I am on gravel ad put my weight on it hard I could.

Locking the rear brake is a sure way to cause a crash. If the brake is strong enough to lock then in an emergency situation when you don't have time to think about it then you will lock the brake which will cause loss of direction. Jim

You had to modify yours to get that safety feature? Mine came that way!

It is interesting to me. Going way back to first bicycles, we used to have contests to see who could do the longest skid. It was always best to have these contests on paved roads where lots of loose gravel was spilled. It wasn't hard to find where I grew up. This behavior extended to first motorcycles. Everybody knew that in order to really get a good long skid, you had to go fast, and there is just so much you can do on a 20-inch bike. I guess it was a sign of the times that most of us had our first motorcycles before me moved to bikes with frames bigger than 20-inches. Anyway, I'm not trying to say that laying down a long skid with the rear wheel of your Commando is a good idea, but I am pretty sure that learning the behavior of the bike under those conditions saved my ass more than once as a young rider once I finally got to ride legally on the roads.

This discourse has less to do with whether or not you can or should lock up the rear wheel and more to do with whether it is a good idea to learn this on a lightweight bike someplace off the highway!

Russ

When I used have my Norton inspected every year they drove the bike and both wheels had to be able to be locked up.The rear should be easy to lock up because 70% or so of the weight is on the front when hard braking (if the front brake works as it should). A big IF.

Check rear drum and shoes for grease from the bearing too.

I suspect the shoe material is the main factor and still in amazment and confidence from Trixie greased and rust caked rear brake until I cleaned it up and adjusted it to barely dragging heating drum fine tune, then its like the factory issues, an after thought feature to half ass pass inspections. Very few riders are able to use the rear for its real purpose in going fast around turns like supermotors do when either too scared to use throttle to swing rear out or not enough power to spin rear to swing out, or to save too much of a low side by a stomp down on rear brake an instant for the fling back up, YIKES! Just rear drag w/o lock up instants in these states will not cut it. It you have lock up shoe grip its not that hard to avoid lock up or quick enough release to regrip and re-apply in time. I've had a number of occassions front brake failed d/t fork leaks on rotor or brake fluid leaks removing all pressure on pads so nothing but wimpy rear brake to carry on rather timidly. Once ya do have fairly easy lock up the rear may be seen more as a maneuvering aiming device rather than for slowing. BTW I wonder if anyone has been able to use up wear out rear shoes, or just got frustrated to try new ones?

I don’t really understand the context of this question, but if you really want to lock up the rear wheel, then yes it is possible with a few certain modifications….. just space out standard brake shoes to .020 thousands inch of brake drum , clamp the rear brake arm on in a position that is greater than 90 degrees to the brake rod/cable when fully on,…and see how easy it is.

rvich said:

You had to modify yours to get that safety feature? Mine came that way!

It is interesting to me. Going way back to first bicycles, we used to have contests to see who could do the longest skid. It was always best to have these contests on paved roads where lots of loose gravel was spilled. It wasn't hard to find where I grew up. This behavior extended to first motorcycles. Everybody knew that in order to really get a good long skid, you had to go fast, and there is just so much you can do on a 20-inch bike. I guess it was a sign of the times that most of us had our first motorcycles before me moved to bikes with frames bigger than 20-inches. Anyway, I'm not trying to say that laying down a long skid with the rear wheel of your Commando is a good idea, but I am pretty sure that learning the behavior of the bike under those conditions saved my ass more than once as a young rider once I finally got to ride legally on the roads.

This discourse has less to do with whether or not you can or should lock up the rear wheel and more to do with whether it is a good idea to learn this on a lightweight bike someplace off the highway!

Russ

Click to expand...

Yeah, my head still hurts from my first highside after locking up the rear brake on my Honda 65 at about 50 mph to see how long a skid mark I could make. :roll:

When I was racing modern bikes with the MRA I found most of the guys would open the rear brake bleeder and allow some air into the line so you had to pump the rear bake a couple times before it did anything. That gave you the chance to think about whether or not you really wanted to use it.

When I was in roadracing school they taught us the quickest way to stop was to pull both levers but don't touch the rear brake pedal. When most of the weight is on the front wheel they didn't want engine braking or brake usage to cause the rear wheel to lose it's ability to track straight.

Of course this applies to pavement. On a loose surface then lightly using both brakes is necessary. Jim

Rich, as kids we played dangerous games on sidewalks corners we'd toss sugar sand to make it interesting, first with clamp on steel roller skates then rear brake only bicycles, with a fire hydrant right at apex just off edge of side walk on corner with traffic. What made it dangerous to us though was we left each dropped bike where is landed to also dodge around going fast enough rear brake did not having anything to do with braking but everything to do with sharper steering and aim to impact hazards dead on or bounce off some to get around landing on the hydrant, pavement or into thorny thick hedge. At first we also had rule rider had to stay with bike where it landed but after your friends just ride/crash right over you screaming at them, we quickly changed that stupid rule. This is where-how I became imprinted that two tire craft were meant to slide around to have fun on. My Peel had better front stopping than my modern or the moderns I tested against on pavement, so never ever used rear to slow as it had no traction or at times even surface contact by maybe 1/2", which is all the stoppie I could ever get on Peel, which could brake even harder but for lack of seat belt to stop me flying over bars.

Do the 850 hydraulic rear brakes have lock up ability as common?

Bernard how does one space brake shoes on rear drum?

[q
Bernard how does one space brake shoes on rear drum?[/quote]

I have explained this on this forum before.