Anyone run rear drum only

Hey Gary, you've got a lot of forest critters hopping around out your way. Yes, its very comforting to have strong brakes front and rear.

Last summer I hit the back leg of a deer as it flew past the front of my bike. That animal was just a blur, as I did some emergency braking using all the power of my front and rear brakes. I had the stock Yamaha disk brakes, and I was thankful they saved my ass. With a rear brake alone, I would have had hospital time for sure.

Even though the stock disks got the job done that day, I have recently installed Brembo 4 piston calipers front and rear. The added power and control of the 4 piston calipers, gives me even more confidence that I can survive the next car/truck/deer that jumps in front of me.
 
There are times you need to swerve instead of brake. But when you need to brake, you need to brake :) :) It doesn't matter that you've been taking it easy just before then because you only have a rear brake.
 
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Bull. Do not confuse a skidding tire with good braking. BTDT more times than I care to count.

A skidding tire does NOT stop you;

Agreed. I did not mean to imply that you want it to skid, just that if you reach the point of it skidding then your brake has enough power.

The key is to have a system that you can easily modulate so you can add just enough brake to slow it down but not enough to lock it. Typically you would run a smaller bore master cylinder on a disk brake to accomplish this. The same can be done on a drum brake by shortening the arm on the back side of the brake lever pivot. I did this on my bike and the difference was amazing. Before, it felt wooden and was just kind of on and off. Now, it has a more linear feel, stops harder, and doesn't lock unexpectedly.
 
Just wondering how your bikes stop with the rear drum only? I currently run a 21" spool on the front and the stock mag on the rear with disc it looks bad but it stops ok. I recently picked up a kx650 drum rear wheel looks the same (or close enough) from what I can tell, but I dont want to put the effort in to respoking it if I cant stop the bike with it.
4 pages and nobody is curious what a kx650 is?
 
2 independent brake systems is federal law. I posted the link. It's on the first page of the document. Been like that as a FMVSS since 1974.
 
Agreed. I did not mean to imply that you want it to skid, just that if you reach the point of it skidding then your brake has enough power.

The key is to have a system that you can easily modulate so you can add just enough brake to slow it down but not enough to lock it. Typically you would run a smaller bore master cylinder on a disk brake to accomplish this. The same can be done on a drum brake by shortening the arm on the back side of the brake lever pivot. I did this on my bike and the difference was amazing. Before, it felt wooden and was just kind of on and off. Now, it has a more linear feel, stops harder, and doesn't lock unexpectedly.

I understand that, I've played with pedal ratios and cylinder bores etc to try to hit the sweet spot between squashy pedal and hard pedal more than once. (Try that with 10 inch wide road race slicks on an 1800 pound car sometime.) That is not what I was talking about.

I was referring to weight transfer, which is something no amount of fiddling with linkage ratios or wishful thinking will ever fix. When a car or bike or whatever decelerates, the front tires take on more of the load. Up to a point, the more weight that's put on them the more grip you get. That makes the front brakes a LOT more important than the rear.(Google 'circle of friction' for more on that.) Ignore this basic fact at your peril.

The other side of that coin is the rear tire gets load taken OFF of it, which produces exactly the opposite effect: as the weight on the tire lessens, its grip lessens as well. That means it is more likely to skid. All the modulation and wishful thinking and 'in your eye' attitude in the world won't help if you have 100 feet to stop and your rear brake only cannot stop you in that 100 feet. (Think 100 feet sounds like a lot? Just for reference, 30 MPH is 44 feet per second and the average human reaction time is in the area of 3/4 second. That leaves you 1.25 seconds and about 60 feet to come to a controlled stop before centerpunching Granny's fender with your head.)

But as I say, you do as you please.
 
On two occasions I had to lock up my rear brakes to lay my bike down into a slide. T
hank God for rear brakes.

Tony do tell................
You can't just leave us hanging like that.
Warning, this may get interesting. In 40 years of two wheeled adventures I can't think of a single time when I thought this will go better if I throw the bike down sideways on the pavement and slide on the various metal parts sticking out of the side of bike. I'm not saying it hasn't happened to me several times I just never did it intentionally.
 
I have laid her down myself, but not intentionally! Damn rear brake locked up while braking heavily and it swapped ends on me! Front only in an emergency stop since then, bur hey, I can lock the front and recover since it is already leading! The front don't wag when I locks, it just slides.
Scott Russell said throwing it on the ground intentionally is admitting defeat, and loss of control. Never stop trying to control the situation. If you brake upright and correctly all the way to impact, you have maximized your survival potential. If you abandon the machine you lower the point of impact, and increase the impact velocity versus maximum braking.
 
Speaking only for myself: all my intentional (and come to think of it unintentional) lay it down slides were in the dirt.

Worst on the street: I had some woman in a Lincoln pull out in front of me once, I was so close I couldn't stop and didn't even have time to brake, all I could do was swerve hard to the right and I wound up going through a bunch of Indian hawthorne bushes. I tore the hell out of that landscaping. And I was going maybe 35 MPH. Good thing I didn't hit the brick apartment gate right behind the bushes.

Best part was I was still upright and PISSED, I chased her to the traffic light and started beating on the drivers' door glass. She floored it, ran the red light and flew through the intersection. Probably wasn't the best way to handle the situation but I guaran-damn-tee you she watched for motorcycles after that.

jd750 brought up a good point: once the rear slides it's much more likely to 'step out' and the front brake won't, we are back to that weight transfer thing again. The front brake takes some practice to learn to use properly, but once you get the hang of it it's much easier to stop the bike quickly. Grab front brake a moment before rear to get the weight forward (this is what your car's brake proportioning valve does for you automatically), then squeeze both brakes until you feel the slide start then back off a tiny bit. It sounds hard to do, but if you find a hard packed dirt road you can practice this till it becomes second nature. Just be ready to dump it once or twice.

It's possible to apply the front brake in a turn but that's an advanced technique, get the feel of straight line stopping first before grabbing a big handful of front in a turn.
 
I was referring to weight transfer, which is something no amount of fiddling with linkage ratios or wishful thinking will ever fix. When a car or bike or whatever decelerates, the front tires take on more of the load. Up to a point, the more weight that's put on them the more grip you get. That makes the front brakes a LOT more important than the rear.(Google 'circle of friction' for more on that.) Ignore this basic fact at your peril.

The other side of that coin is the rear tire gets load taken OFF of it, which produces exactly the opposite effect: as the weight on the tire lessens, its grip lessens as well. That means it is more likely to skid. All the modulation and wishful thinking and 'in your eye' attitude in the world won't help if you have 100 feet to stop and your rear brake only cannot stop you in that 100 feet. (Think 100 feet sounds like a lot? Just for reference, 30 MPH is 44 feet per second and the average human reaction time is in the area of 3/4 second. That leaves you 1.25 seconds and about 60 feet to come to a controlled stop before centerpunching Granny's fender with your head.)

I know all that stuff. The guy was only asking about the difference between a disk and drum on the BACK WHEEL.
 
It's possible to apply the front brake in a turn but that's an advanced technique, get the feel of straight line stopping first before grabbing a big handful of front in a turn.

I can reliably brake with the front rolling into a turn, or if need be, mid-turn, with the front. Another thing to practice while you are rolling around in the land where nothing goes wrong.:bike:
 
I can reliably brake in a turn as well, in fact I wish the front brake was more powerful. I will probably fiddle with M/C bores at some point because I like the idea of a two finger stoppie on demand. Not that I'd do it, I just like one that powerful.
 
I know all that stuff. The guy was only asking about the difference between a disk and drum on the BACK WHEEL.

Here's the answer: with stock linkage, master cylinder etc a rear disc brake will be less likely to overheat, fade or lock up (thus is more controllable) but will require more pedal pressure than a drum setup. It was never designed or intended to supply 100% of the bike's braking power thus the stopping distances will be longer.

A drum brake will be harder to modulate, thus harder to control and since it will be asked to do 100% of the braking when it was designed to supply about 30% will be much more likely to overheat and fade. It too will have a longer stopping distance than if it is used in conjunction with a front brake.
 
I can reliably brake in a turn as well, in fact I wish the front brake was more powerful. I will probably fiddle with M/C bores at some point because I like the idea of a two finger stoppie on demand. Not that I'd do it, I just like one that powerful.

I can stoppie my SV, with the front tire fully inflated! That's cuz my big ass plants that front tire something fierce! You might get there with an SV front end on an SX. The steering head is at 27 degrees VS 24, and the XS is a little heavier, but the brakes are pretty efficient.:bike:
 
I can reliably brake with the front rolling into a turn, or if need be, mid-turn, with the front. Another thing to practice while you are rolling around in the land where nothing goes wrong.:bike:


I've never liked doing it but I brake front and rear in turns when the need arises. For those who might not have ever rode there, sooner or later you will learn to use front and rear brakes in turns when riding the Appalachian back roads. Hopefully sooner.
 
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