Mechanical Drum vs. Hydraulic

[Richard D]

I know neither is as good as a disc. That said, here’s my situation.

I am collecting parts for a period correct ’55 Panhead project, in a ’48 wishbone. I have found both a mechanical drum(would still need to find the plate, shoes, etc.) and a complete hydraulic rear brake. This bike was run before with a juice drum, so the cross shaft for the mechanical has been cut off. I have another tube and shaft I can put on there. Will not have a front brake. I know the mechanical will look a lot cleaner, so I’m leaning that way, but how much better will the hydraulic stop? This bike will be mostly for show and cruising around, no high speed blasts on the freeway or lane-splitting in heavy traffic.

[=mike=]

On the '56 I had a drum in the back and ( later ) a sportster drum on the front . It stopped pretty well , considering it was a stroked and very fast motor , with only the rear break . I did a lot of freeway fast riding and lots of light to light terrorizing and never had many situations that I thought " boy I sure would like to be able to stop better " .

Obviously I never needed it so it was never a problem . Hard to say when you're going to need it though . I'd say if you only plan on round town cruising and putt putting , either should be fine for you . The juice would be a little more effective by design , but probably not noticeably so . I'd say either would do what you want them to do in the end .

[vtwinmotors]

I have mechanical on one of my panheads and disc on the other two. I like the mechanical look. I also would have done the hydraulic drum if I could have found one at the time I was putting the last one on the road. But the dice set up with a little work was easy off a softail. Good luck

[Richard D]

Originally Posted by vtwinmotors

But the dice set up with a little work was easy off a softail. Good luck

Dice setup?

[ralphiejantz]

my pops has the juice brakes on his 65 pan and they stop much better than the mechanical and in my opinion look just as well on a period correct build as a mechanical brake does

[Richard D]

That's what I was thinking, plus I already found the juice stuff. What do you recommend for a master cylinder? I'll be running mids.

[Rubone]

I am collecting parts for a period correct ’55 Panhead project, in a ’48 wishbone.

Period correct? What period are you talking about! Juice on a rigid is a '70s thing. Never saw one set up that way before. I did one in '73 and people thought it was weird!
Robbie

[Tattoo]

I say mechanical. It will stop great if you work on it to get it centered. Once the back wheel locks up how much better is a juice brake or disc going to stop??

[Larry T]

Originally Posted by Rubone

Period correct? What period are you talking about! Juice on a rigid is a '70s thing. Never saw one set up that way before. I did one in '73 and people thought it was weird!
Robbie

From Richards other threads, it is a 70's style scooter--raked, twisted springer, molding, etc. Looks good to me.

If you've got the juice brakes and the bike is set up for them then use 'em. Here's mine, but it has some modern stuff on it. Most folks don't notice.

Mid 70's would more than likely use a Wagner style master cylinder.
Larry T

[spsgold]

Originally Posted by Larry T

From Richards other threads, it is a 70's style scooter--raked, twisted springer, molding, etc. Looks good to me.

If you've got the juice brakes and the bike is set up for them then use 'em. Here's mine, but it has some modern stuff on it. Most folks don't notice.

Mid 70's would more than likely use a Wagner style master cylinder.
Larry T

Thats Clean!

[ryangobie]

Originally Posted by Tattoo

Once the back wheel locks up how much better is a juice brake or disc going to stop??

Winner.

[caschnd1]

Advantage of disc: Won't fade, easy to modulate the point between braking hard and locking up.

Advantage of juice drum: Easy to modulate the point between braking hard and locking up.

Advantage of mechanical drum: Simplicity, clean looks, still stops really well.

I use mechanical drums on my chopper.

-Craig

[Tattoo]

Originally Posted by caschnd1

Advantage of disc: Won't fade, easy to modulate the point between braking hard and locking up.

Advantage of juice drum: Easy to modulate the point between braking hard and locking up.

Advantage of mechanical drum: Simplicity, clean looks, still stops really well.

I use mechanical drums on my chopper.

-Craig

That's a good point on fade. I have mechanical brakes on my Pan and Knuckle. If you hear the back wheel locking up, back off the brake a little bit -- it works real good, just like juice. I've never had my mechanical brakes fade if they are set up right. I live where there are a lot of mountains and curves, and I ride up people's ass all the time with late model bikes. Haven't had any late model disc brake bike pull away from me yet. I'll take a mechanical over a juice drum any day, and personally I think a disc looks stupid on a rigid Pan or Knuckle bike unless it's an S&S motor - that's different if you're building a look-alike.

[Richard D]

Lots of good info here. I think I will run the juice since I have already found all the parts, and won't have to weld on the cross shaft. If I hate it I can take it off.

[Irish Rich]

Originally Posted by Rubone

Period correct? What period are you talking about! Juice on a rigid is a '70s thing. Never saw one set up that way before. I did one in '73 and people thought it was weird!
Robbie

It wasn't just a "70's thing...", chopper guys were swapping out juice drum assemblies in place of their mechanicals long before the '70's came around. It was a pretty common swap. Here's Dick Allen's juice setup on his rigid chop, circa 1967. He was far from the first guy to do it, too.......

[tlingit]

Wheel cylinder: Wagner Lockheed. By the way, now made by Wagner in China I'm told! There are different Wheel Cylinders configurations depending on year of hydraulic rear brake setup.

Master cylinder: Wagner again, which is a 3/4" bore.

[fatass]

I don't think there's anything wrong with the juice brakes. It's like running a flathead; you KNOW it's not gonna beat a Ninja, so you "ride accordingly".

I really, really like my juice brake. If you've got all of the parts (INCLUDING the correct drum bearings and the seemingly elusive internal spacer), I think they're a good compromise between mechanical coolness and disc stopness. When I actually think.

[Richard D]

I don't have the parts in hand yet. I'll be hitting you guys up when I do to make sure I set it up right.

[Trent]

Both work just fine and both look nice and clean. Just make sure your shoes are arched correctly and you will be happy with either.

[BORED]

I think the juice drum brakes work as well as some of the early single pug banana disk calipers.
+1 with what Trent said about shoes arched correctly, my 67 front aren't (maybe fallen arches?!) and it's no bueno on stopping.
Are you runnin a front brake?

[ElekVins]

What's the best way to modify a rigid frame for a juice set up?
I've seen a tab in the bottom of the axle plate or modify the drum itself for the tab to fit between the legs... In the second option, how do you adjust the chain? Does it become a pain in the ass?
What your opinions and experiences on this? (pictures welcome...)
My rear axle plate have already been molested by previous owner:

[old.wrench]

I'm running a hydraulic drum (juice) on my rigid shovel. It's the later mid-star hub version with the bearing in the drum. Real solid set up with good braking and a nice feel to the braking action. I use the Wagner master (the cast looking one), it fits the look of the bike better than squared-off billet looking type. If you don't have a tab on your frame for the brake plate anchor you'll need to add one. You can either fabricate the tab or buy one and weld it on in the proper location at the bottom of the left axle plate.

For elekvins: the tab for anchoring the brake plate has a slotted hole to allow for chain adjustment

Regards,
Geo.

[ElekVins]

Originally Posted by Irish Rich

It wasn't just a "70's thing...", chopper guys were swapping out juice drum assemblies in place of their mechanicals long before the '70's came around. It was a pretty common swap. Here's Dick Allen's juice setup on his rigid chop, circa 1967. He was far from the first guy to do it, too.......

This Dick Allen set up looks real clean...
The tab is welded to the upper rear leg?
Does anybody have a profile picture of it? Or from a similar set up?

[ElekVins]

Originally Posted by old.wrench

For elekvins: the tab for anchoring the brake plate has a slotted hole to allow for chain adjustment

Regards,
Geo.

Thank you Geo, yes i know that from my swing arm set up.
My question was if you put the tab between the legs instead of below the axle plate, does it make chain adjustment a problem?
Is it in the way of the adjuster, or there is enough room for the adjuster and the tab?

[old.wrench]

Elekvin, on the D.Allen bike the brake plate is rotated clockwise compared to the stock installation which would put the brake anchor bolt to the front. It's a little hard to tell from the angle of the pic. It also looks like he used a hard line all the way from the master to the wheel cylinder which will give your brake a better feel than the fat soft ones (as long as you use steel line).

[ElekVins]

Yes that what it seemed to me, just curious to see how his tab looks... Seems to be weld under the upper leg.
I also wonder if he modified the drum plate (the bolt that locks the drum itself) or if he left it stock...
Any idea?

[jbfrmca]

looks like mr allen just used the stock mech brake stay to anchor his juice setup.

[old.wrench]

Originally Posted by ElekVins

Thank you Geo, yes i know that from my swing arm set up.
My question was if you put the tab between the legs instead of below the axle plate, does it make chain adjustment a problem?
Is it in the way of the adjuster, or there is enough room for the adjuster and the tab?

I've personaly only mounted the tab at the bottom of the plate, but I'm pretty sure you could squeeze it in at the front. When you mount the tab on the bottom, like stock, the hole in the tab only has to be egg-shaped and not really slotted because as you slide the axle fore and aft for chain adjustment, the brake plate will rotate around the axle. The closer you mount the tab to being in the same plane as the axle slot, the longer the slot in the brake plate tab will have to be.

[old.wrench]

Originally Posted by jbfrmca

looks like mr allen just used the stock mech brake stay to anchor his juice setup.

Right.

[ElekVins]

Originally Posted by jbfrmca

looks like mr allen just used the stock mech brake stay to anchor his juice setup.

I had the feeling he modified the stock mech brake stay, because I don't see the bottom of that stock tab...? (on the lower leg)
But I may be wrong, no offense intended on my side

[ElekVins]

a real profile pic would clear my mind on this...

[Richard D]

Will this M/C work, or should I look for another?

[old.wrench]

I just went out and took a look at the difference between the my pan and shovel. It looks like you could make a modified spacer for the juice plate anchor so it would fit in the slot for the stock mechanical brake anchor. You might have to trim the length of the juice brake anchor stud a bit as well so it will clear the axle adjuster. Set up in that fashion, it would probably help to remember to bleed the lines with the wheel cylinder horizontal, like stock.

Regards,
Geo.

[old.wrench]

Originally Posted by Richard D

Will this M/C work, or should I look for another?

It's the right type. Unless you are certain that its all good, a rebuild kit is pretty cheap. That way you can be sure you've got the right guts in it so that valving is correct for a hydraulic DRUM brake with a wheel cylinder.

[ElekVins]

Thanks Geo !

Originally Posted by old.wrench

Set up in that fashion, it would probably help to remember to bleed the lines with the wheel cylinder horizontal, like stock.

And that makes sense too... I might not have think about it in the first place !

[ElekVins]

Still if somebody around here as a profile picture of such as Dick Allen set up... I'll be glad to see it !

[Larry T]

Originally Posted by Richard D

Will this M/C work, or should I look for another?

That should do it. The only difference in the MC for a disc brake and the MC for a drum is that the drum brake setup has a residual valve in it. It comes with a kit, so everything should be pretty simple.
Larry T

[notcool]

There has been lots of discussion about this before.
Both work great if they are setup right! Both will skid just the same or work like crap, you have to know what you are doing...
As someone who as a '58-62 juice drum setup apparently like dick allens in a rigid frame using the stock brake stay... if i did it again i would do a mechanical brake for simplicity...

But those early juice drum backing plates have a bolt on brake stay and you can take it off and easily modify it to do what ever you want.

Arcing the shoes to the drum helps a lot with ANY drum brake.

[ElekVins]

Originally Posted by notcool

There has been lots of discussion about this before.
Both work great if they are setup right! Both will skid just the same or work like crap, you have to know what you are doing...
As someone who as a '58-62 juice drum setup apparently like dick allens in a rigid frame using the stock brake stay... if i did it again i would do a mechanical brake for simplicity...

But those early juice drum backing plates have a bolt on brake stay and you can take it off and easily modify it to do what ever you want.

Arcing the shoes to the drum helps a lot with ANY drum brake.

Notcool, do you have a profile pic of your set up, please?

My juice drum is from '67 so I guess I don't have this bolt on...?
Mine should be weld to the plate if I remember correctly...?

[Irish Rich]

The best "profile" shot I have....hey, it's not like we can get Dick to take any additional photos for us. You can see the shortened pin located in the mechanical brake slot on his frame.

Sidenote: Also notice that Dick's rear footpegs are actually bolted through the rear of his horseshoe tank. Joe Hurst has that oil tank now....

[ElekVins]

Thank you Rich !
This profile is good enough to see he apparently let the rear brake stay stock

[notcool]

Rich that is awesome!

Here is about the only pic i have on this computer where you can kinda see, but yes an earlier juice drum setup is easier to do this.

[M.O.Ther]

The shortcoming of using the rigid frame's anchor tab between the legs rather than welding a tab on the bottom is that it makes the brakes more difficult to bleed. To get all the air out, you'd have to bleed the wheel off the bike , with the wheel cylinder at the 12:00 position, and then install it without breaking any of the line connections.

[Tattoo]

Run the Mechanical you will be glad you did in the long run.

[ElekVins]

Thank you for all this. (Notcool I was looking at your set up in the GKM feature, there a good pic of it...)
I guess my juice brake bein' a later model and the anchor tab between the legs of my frame bein' already cut off, I should rather weld a tab on the bottom... for some reason I find myself bleeding my brakes often...
I was just after the cleaner minimalist look of the tab between the legs.
and Richard D, sorry for hijacking your thread...

[kickstarts]

With no front brake, if you pop a line or blow out a seal in the wheel cylinder, you'll have no brakes. I'd go with a mechanical brake if I were only running a rear.

[Larry T]

Originally Posted by kickstarts

With no front brake, if you pop a line or blow out a seal in the wheel cylinder, you'll have no brakes. I'd go with a mechanical brake if I were only running a rear.

And linkage and pins could come loose on a mechanical setup.

[kickstarts]

Originally Posted by Larry T

And linkage and pins could come loose on a mechanical setup.

True, but you can see, inspect and correct those easily. You can't see inside a master bore or the seals in the wheel cylinder or the lining of the brake hose until they fail at speed and if that happens and it's your ONLY brake, panic time.

I used to run only a rear Sifton years ago and when the body decided to not float on the axle, things got super hairy. No thanks. Shitcanned it and went back to 2 brakes. I have run rear only with a mechanical and felt better about it.

[Larry T]

I guess the point I was trying to make is that there probably isn't a LARGE chance of catastrophic failure (on either system) without warning (fluid leaks or hose bulge on hydraulic, rattles or ?? on mechanical). And I can honestly say that I don't remember a fluid blowout on any bike with hydraulic brakes I've ridden since 1975 (mechanical brakes before that and no problem with them either).

If Richard's bike were mine, I'd probably go with hydraulics because it is set up for hydraulics right now (maintain the history of the way the bike was built in the 60s/70s?) and he has the hydraulic brake setup for it. And they work.

But I might set it up for mechanical brakes if I like the looks better (cleaner?), or I was thinking about restoring the frame at some time. And they work.
Larry T

[HD48FL]

Originally Posted by Larry T

I'd probably go with hydraulics because it is set up for hydraulics right now (maintain the history of the bike?) and he has the hydraulic brake setup for it. And they work. Larry T

I'd say run the juice setup as you mentioned the crossover tube is missing on your frame.

[kickstarts]

Originally Posted by Larry T

I guess the point I was trying to make is that there probably isn't a LARGE chance of catastrophic failure (on either system) without warning (fluid leaks or hose bulge on hydraulic, rattles or ?? on mechanical). And I can honestly say that I don't remember a fluid blowout on any bike with hydraulic brakes I've ridden since 1975 (mechanical brakes before that and no problem with them either).

If Richard's bike were mine, I'd probably go with hydraulics because it is set up for hydraulics right now (maintain the history of the way the bike was built in the 60s/70s?) and he has the hydraulic brake setup for it. And they work.

But I might set it up for mechanical brakes if I like the looks better (cleaner?), or I was thinking about restoring the frame at some time. And they work.
Larry T

You're right. There isn't a large chance of failure.

I've had a rear brake only juice problem in the past and it scared me badly enough to adjust my thinking. I personally like the look of the juice rear setup but nowadays I'm a 2 brake, just in case, kinda guy.

[Larry T]

I'm a two brake kind of guy myself. I've never run a spool hub in 40+ years of riding and I don't see a reason for me to start now.

Well, I see the bottom of my coffee cup (slow start today). Guess I'll go do a little work. I need to adjust the brakes on a customers 49 Pan. Kinda ironic, isn't it?
Larry T

[Danny F.]

^^ Is that '53-'55 Vette yours Larry..?

[Larry T]

Originally Posted by Danny F.

^^ Is that '53-'55 Vette yours Larry..?

Danny,
No, it's a customers 1954. He brought it in for a tune-up and it's turned into a major headache (mostly the 3 side draft carbs). I've been getting a lot of stuff to work on that folks have bought with the idea that they are in good shape, when in reality they're good enough to crank and run across the auction block and not much more. Then they bring them to me to get them in good enough shape to actually drive.

The Panhead is the same kind of deal, but I'm kinda enjoying getting it road ready.

I've got a numbers matching 425 horse 409 63 Impala in here that I'm rebuilding the engine for another guy. It's a pretty nice deal too.

Trouble is, I'm busy enough with customer work, that I'm not getting much done to my stuff.
Larry T

[ElekVins]

Originally Posted by old.wrench

It also looks like he used a hard line all the way from the master to the wheel cylinder which will give your brake a better feel than the fat soft ones (as long as you use steel line).

Originally Posted by M.O.Ther

To get all the air out, you'd have to bleed the wheel off the bike , with the wheel cylinder at the 12:00 position, and then install it without breaking any of the line connections.

Must be a little complicated with hard lines if you have to rotate the drum every time you need to bleed...
Is there a trick or I'm missing something here?

[Danny F.]

Originally Posted by Larry T

Trouble is, I'm busy enough with customer work, that I'm not getting much done to my stuff.
Larry T

That sounds so familiar...

[JOCK E SHIFT]

Originally Posted by kickstarts

With no front brake, if you pop a line or blow out a seal in the wheel cylinder, you'll have no brakes. I'd go with a mechanical brake if I were only running a rear.

i sheared off a brake cam at .70mph..theres NO telling when a 50yr old part will fail..it took me 20 years but now i run front and rear brake..when you fly threw red lights u will change your mind like i did.

[kickstarts]

Originally Posted by JOCK E SHIFT

i sheared off a brake cam at .70mph..theres NO telling when a 50yr old part will fail..it took me 20 years but now i run front and rear brake..when you fly threw red lights u will change your mind like i did.

I run front and rear always. I ran rear only until I slammed into a toll booth door when my rear mechanical failed 20 years ago. The toll taker was pretty shocked to say the least