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    Front vs. rear brake panic stop?

    I don't know the answer to this one and maybe one of the younger MTBers with crash pads could test this for me.
    I recall as a child that the old coaster brake cruisers could lock up the rear wheel and skid sideways or even do a 180* turn to stop. The skinny tire "English Racers" with front brakes could only stop going straight ahead in an upright position and were at risk of going OTB while doing it. It has occured to me that with fhe wide tires most of us run and the large front rear disc brakes modern bikes have this is still a valid question. The real question being is if one method is better than the other to say avoid a car that pulls out in front of you and stops, you only get one chance to choose which method you want to use.
    Front brake- you're commited to staying upright and not going OTB.
    Rear brake- you lock the rear and get it swung around ASAP but can lay the bike down.
    Laying the bike down has the advantage that the bike takes the impact, OTB it's your head and neck.
    I haven't used the rear brake technique since forever, but maybe it should still be in my bag of tricks.

    #2
    With disc brakes, always use the 60/40 rule (same as cars). 60% front and 40% rear. This method will give the best stopping with the best chance of not skidding or laying the bike down. This method should be practiced a lot to get the feeling of your brakes and how they react to quick actions and learning how much pull is needed. The disc rotors are designed to prevent locking up but when you loose any amount of traction due to road conditions, sand, gravel, etc.., you will lock up. I often practice slamming the front brake just before the back brake and let the rear brake assist with the front. This is across the board with every two wheeled vehicle and disc brakes, hope this helps.

    Yesterday, I had a close call and this method stopped me very quickly and did not slide at all.

    Comment


      #3
      I know for regular stopping that's the way to go. But I'm wondering if laying the bike down in an emergency will stop quicker. I know moto guys do this (I think).
      At 65 years old I don't think it's a good idea to try this experiment myself.

      Comment


        #4
        Laying the bike down was a technique I remember hearing Harley riders mention. I've also heard the same contingent say, don't use the front brake. I suspect once you do that, you surrender directional control of you and risk getting tangled up in multiple hundred pounds of motorcycle. Staying on your tires and braking hard will stop faster than rolling and tumbling on your arse. Also, would you rather go over or under a car?

        The Motorcycle Safety Foundation (MSF) training recommends hard braking right off, both wheels, and if you hear chirping / sense a rubbery feel up front, back off on that wheel.

        Now, how much does the hopefully centered e-bike component weight help us from doing a stoppie, I dunno. Combine that with the bigger tires we often have. My bikes have long wheelbases, and so far, even with 204mm front rotors, have not lifted the rear wheel.

        And guess what, Bosch has developed e-bike ABS. I owned a few BMWs that had ABS - very worry-free in rainy conditions and could be braked straight-line as hard as you please.
        Last edited by ncrkd; 07-23-2019, 05:03 PM.
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        Comment


          #5
          If you're going to do the lay down technique you stay off the front brake to keep from getting tossed over the high side if the front tire grabs while on it's side. I'm glad you brought that point up for those who've never ridden the old cruisers. You definitely don't want to do a barrel roll on a full size Harley. If for some reason the bike starts to swap ends you can switch to the laydown, but release the front brake if you do.The old coaster brake bikes only had a rear brake and they would skid forever unless you got it sideways, or brakes forward with a 180 turn. On those bikes it was the only game in town. That's why I'm not sure how it actually compares. But I have seriously out braked some bullys on 10 speeds back in the day. I bought a couple new Schwalbe tires, and one of my old ones has had 3 flat repairs.Maybe I'll get some of that testosterone gel or spray and lay down some skid marks like the good old days. Medicare covers anything. You won't go under the car if it's already in front of you, unless it's a jacked up 4x4. Even then the laydown might let you go all the way across underneath. Tom Cruise does it all the time.
          I can usually lock my front tire on pavement so there's not much left on the table for straight ahead braking.






          Last edited by Retrorockit; 07-23-2019, 05:51 PM.

          Comment


            #6
            Do you mean a brake-cut off sensor? I wonder if it's necessary. I purchased a bike from ebikebc and they mentioned that it's not necessary to install. The hydraulic brakes are suppose to be strong enough to support you in case of a panic. Maybe best to talk to a mechanic because they'll know best.

            Comment


            • Retrorockit
              Retrorockit commented
              Editing a comment
              This is about whether an old school coaster brake riding technique still has any validity.Nothing to do with brake switches or even e bikes especially.

            #7
            IMO, the only time to lay down a bike, is to avoid getting catapulted. For example, front end washes out under braking, in a turn. If you let up, the bike rights itself and flips you over the "high side". You land, invariably breaking a collarbone. It's usually FAR better to stay on the brakes and slide out. Don't High Side.

            Brake blending is SO dependent upon the bike. My fat bike will put me over the bars, I need to be careful. Some bikes don't even do that.
            Fabrication is fun! Build something today. Show someone. Let them help. Inspire and share. Spread the desire.

            Comment


            • tklop
              tklop commented
              Editing a comment
              I agree. Rarely would I choose to go down on purpose--but it's definitely better than going over the high-side (been there, done that, got the scars to prove it)...

              Also, bicycles are very different than motorcycles. It's not just their weight--it's their size, and the way that weight's distributed too. There are very different forces going on--in spite of both conveyances having two wheels. What works for motorcycles just isn't always going to turn out working the same way for bicycles.

              I've ridden bicycles that had such stable geometry, that I could recover from a full-on middle-of-a-curve front-wheel skid (akin to what we used to call a "power-slide" when I was a kid)--without even having to put a foot down--just steering through it; and I've ridden others (especially commuter bicycles with front-suspension)--which have thrown me violently on the ground at the first hint of a front-wheel slip! It helps very much to know your machine.

              I've long heard debates along these lines, and I firmly believe that in any given situation, no matter what I'm operating--that remaining in control of my machine is my best possible option. If I'm about to broadside a car--who popped out of a blind corner, I've already screwed up by approaching a blind corner too fast... Now--it's not a matter of "let's try this" --it's a matter of braking. Hard. Right into the point of impact. Why? Because if I dump myself on the ground, I will not scrub speed off nearly as quickly--and in the end, I'm gonna hit that car a lot harder. If I was only going "a little too fast" --maybe my front-tire won't even leave a dent--and I can offer my sheepish apologies--and a handshake--and we can all be on our merry way.

              If I do clip this hypothetical car pretty good, I might "potato-chip" my front-wheel, and get tossed into a shoulder-roll--but otherwise, both me and the bike will likely be undamaged. Unless it's going to be a fatal impact, let's face it: Treating my front-wheel as a bumper isn't the worst thing. Even if a front-wheel needs a new rim, or relacing--that's still likely to be cheaper than replacing a ton of ground-up e-bike components--(not to mention the flesh) which I'd otherwise have needlessly sacrificed to the gods of asphalt.

              One thing that does work on both bicycles and motorcycles, is a technique for braking in a turn--to avoid the front-end washouts you describe (well it works pretty well anyways). Basically--square the handlebars, then brake HARD--then ease off, turn some more, then square the bars again--and brake HARD. The curve gets separated into multiple straight-line segments. This works really well (learned it in a motorcycle rider training course) --especially when the road-surface is compromised. If you're going to skid under hard braking--then at least you'll be skidding in a straight line--upright--and remaining in control.

              Interesting discussion...

              Best advice I have to offer--if it seems you're often having scary experiences on your bike, e-bike--or your motorcycle for that matter--is to reduce your speed, especially until you've learned to anticipate hazards better. Your adrenaline is there for emergency use only. Don't manufacture emergencies needlessly.

              All the best, everybody!

              Tklop
              Last edited by tklop; 07-24-2019, 04:10 PM.

            • JPLabs
              JPLabs commented
              Editing a comment
              Good insights, thanks!

            #8
            What I do when the bike is going down is don't put my hand out to stop the fall. I let the end of the handle bars hit the gound first.This usually turns the front tire into the ground and lifts the bike back up some. Then take the rest of the fall on my outer arm and shoulder.

            Comment


              #9
              It's true that a big inch Harley is about as different form an E bike as you can get. The reason I brought this up is I remember being chased by a bigger kid on a 10 speed, and I did a coaster brake turn 180* without putting a foot down. So laying the bike down is probably a Harley thing. The other guy went into the curb with his front brake locked and OTB. My bike was still going backwards. I was pushing down on the pedal as hard as I could and it was still coming up. The bike finally stopped going backwards and I rode away. When I looked back his fork was snapped and the wheel was hanging by the brake cable. Definitely a scene from Wiley Coyote.
              So it's worked for me, but then again on that bike there was no other option. Once you start down the path of a bootleg turn like that you can't change your mind.
              I really like the tip of straight braking in a turn. It rains a lot around here. Might work in a car also.

              Comment


                #10
                Not a highjack, somewhat related.........Any here use the dual cable, single lever brake lever? Both front and rear actuated from one single pull lever? Seen Sturmey Archer sells these, and considering swapping out my separate front and rear levers for a single. See any issues? I would imagine it is 50/50 front/rear, although one COULD adjust at the brake itself to make one or the other do more of the work. I use 90mm drums on front and rear. LOVE them. Can not imagine needing more, but would like to clean up some of the cables on the bars.

                Comment


                  #11
                  You definitely don't want the front brake applied if you do this. The front wheel grabs and you go over the high side for very serious face plant. Basically the real wheel swings around to beocome the front, and the bike is laid down somewhat for a lower center of gravity. I have personally out braked a skinny tired road bike on a 24" cruiser doing this.

                  Comment


                    #12
                    I was thinking the dual leaver set to do front 60/ rear 40. But could leave right as rear only for that purpose. I can see how to easily combine both cables at the rear hub so either activate it. While the front is only attached to the dual. Then u have both ways. But only know I can do it with drum hub brakes. Will look into this. As far as tires, my cruiser sets on 26x3"s on 65mm rims.

                    Comment


                    • tklop
                      tklop commented
                      Editing a comment
                      The dual-pull single brake-lever will work, and yes--by adjusting each brake independently you should be able to get it porportioned how you like. My bakfiets project uses this concept to actuate both front-wheels' brakes simultaneously. Because the brakes are left and right, they've got to be matched as closely as possible to keep from pulling left or right. But you can certainly dial in whatever differences you'd like, when using the handle for front and rear brakes.

                      To accomplish the same thing, there is also an alternative--a cable-splitter. Elvedes makes a cable-splitter set--part number KA2017161 --and there's versions from other companies also. (All my shopping links are coming up with Dutch vendors--useless to you--so the part-number seemed a more helpful thing to post).

                      The cable-splitter allows you to use any normal brake-handle to actuate two brakes.

                      I've now opted for this method, instead of the double-pull brake-handles, because I wanted e-brake switches, as well as a parking-brake function. I couldn't find both on a double-pull handle, and I didn't want to do the whole messy add-on after-market brake-sensor-mod. (epoxy, and whatnot).

                      Keep in mind that your "dialed in" settings--between the two brakes--will not adjust for weather or road conditions. Separate human hands actuating separate brake-handles can make instantaneous fine adjustments. You're going to lose some of that fine-control by using only one brake-handle. Because of this, it's possible your emergency-braking might be less than ideal--even though your brake-porportioning might be right at that golden 60/40. You'll want to familiarize yourself with any differences in your bike's behavior (braking in turns, panic-stops, etc), but in a safe place. You will not want to explore the boundaries of your new operational parameters out in traffic--facing an emergency situation. Temperature changes (expansion and retraction) will affect your cable-lengths too--and because your front cable is shorter than your rear--this will affect your braking-ratio. Regular adjustment will likely be required--to keep things "just right".

                      Anyways--I just saw your post--and thought I'd share my own two-cents worth--when it comes to those "one-handle two-brakes" situations.

                      All the best!

                      Tklop
                      Last edited by tklop; 09-06-2019, 04:01 AM.

                    • Retrorockit
                      Retrorockit commented
                      Editing a comment
                      Brake balance aside from weather, and surface differences, uphill or downhill braking are seriously different also.

                    • tklop
                      tklop commented
                      Editing a comment
                      Also good points, Retro--further supporting the idea that one should get used to the "new" handling--when going to this kind of system--and further supporting the notion that frequent adjustment is part of the deal. If approaching a scary downhill--stopping to make that adjustment would be prudent!

                    #13
                    Some awesome info there tklop. I will look at those splitter/ combiners for the cable. For your brake sensor you could do like I did and use a gear sensor on the brake cable. It is a simple mod I can explain if interested. I use it to activate my brake light and kill the motor without adding more wires to the handlebars. It is only on the rear brake for now, front brake does neither. I like that way so I can tap the rear lever to kill motor, I also have the stop light wired to my momentary horn button so I can tap it as a "back off" signal to cars.

                    Comment


                    • Retrorockit
                      Retrorockit commented
                      Editing a comment
                      I paid $800 for the Scout wagon with 302 already in it. Used car dealer couldn't get it to crank. Moved the battery ground strap from a rusty fender bolt to the engine block. The only way I could keep my license in the 55mph days was to go offroading and then drive home normal.Offroading in South florida is a very relative term. Fire roads, and some slick as ice tidal mud flats

                    #14
                    From my moto racing days it was all made very clear to me

                    On smooth hard surface terrain going straight, by far, nearly all the braking should be with the front

                    The more you are turning, the looser the surface and more uneven then the braking shifts from front to rear depending on how much these variables are contributing


                    If you have to bail, low-sides are by far the way to go - high-side bailouts suck and are much more prone to injury


                    Practice, practice, practice


                    I remember my first moto that had ABS (R1100GS). When I first got that moto, on the street there was a couple of times when learning the machine the ABS may have prevented me from swapping ends on a panic stop. OTOH the ABS was absolutely outright dangerous on dirt surfaces and at least they made them easy to disable.

                    After several thousand miles, I'm past the learning and "wearing" the moto (like wearing a glove) - i.e. one no longer thinks about the mechanics of riding like which brake to use, the gear or when to shift, etc. - it's all at the abstract and you think only about where the wheels *will* be and the rest just follows... One of the limits to your speed is how far out you are ahead of the machine - if you aren't racing you need to be at least able to come to a stop by the point that you are out ahead of you... At this point I hated the ABS and removed it - I could do a better job than it in any conditions albeit that was a very primitive ABS


                    Bikes are pretty much the same

                    If your bike isn't street only, get time in the loose stuff - it will make you much better on the hard surface

                    Comment


                    • Retrorockit
                      Retrorockit commented
                      Editing a comment
                      Many years ago i had friend with an Econoline who likes to follow me around offroad in my Scout. I told him about the thumbs. 20 years later he saw Pierre Lartighe walking around the Paris Dakar Rallye with his thumbs in splints. He was shocked because I had warned him about that so many years before.
                      You would have liked the 66 Scout P/U. 302 Ford set behind the fornt axle,Posi rear axle <30000#. Automatic locking hubs that freewheeled under braking. A downshift would lock up the rear but the fornt was 2WD until you applied power. Braking was done sideways, Power applied at the apex with wheels straight ahead. It was my street car also. This was mid "70s when power was down on everything. I could actually give sports cars the shits on the street. Best sand tires are big high profile street radilals
                      anyway.The whitewalls gave it a touch of class.
                      Last edited by Retrorockit; 09-10-2019, 06:57 AM.

                    • AZguy
                      AZguy commented
                      Editing a comment
                      The good/bad old days for sure =]

                      That van was an '80 (give or take one or two) Dodge B100 with a 360ci 4-bbl... bought it for $800... Thing had juevos but back then the speed limit nationwide was 55 and most the places I was running it was enforced... Still would fly when I felt the need. Bought it with low-profile tires on it and replaced the rear with big mud tires so had that stink bug stance for sure... shag carpet and paneling... just needed to hang out by the high schools (maybe in a nun's habit?) to really fit the profile...

                      Even the two wheel drive climbed just about anything - kept a 600cc DS moto in the back.... you know... for traction ;-} Served me well for my first couple of years hang gliding until I finally moved up to a big '89 3/4ton econoline...

                      Sometimes I'm nostalgic for the simplicity (and fun) of life back then...

                    • Retrorockit
                      Retrorockit commented
                      Editing a comment
                      I paid $800 for the Scout 4x4 wagon with 302 already in it. Used car dealer couldn't get it to crank. Moved the battery ground strap from a rusty fender bolt to the engine block. The only way I could keep my license in the 55mph days was to go offroading and then drive home normal.Offroading in South florida is a very relative term. Fire roads, and some slick as ice tidal mud flats. I will take a 2wd with a limited slip over an open diff 4x4 any day. But yeah 2wd needs some weight in the back.
                      Last edited by Retrorockit; 09-10-2019, 11:10 AM.
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