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Front vs. rear brake panic stop?

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  • Retrorockit
    commented on 's reply
    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, 05:57 AM.

  • AZguy
    commented on 's reply
    That thumb thing is funny stuff for sure! I had an old beat-up van with manual steering that was my hang vehicle (for hauling hang gliders around) - I had to warn the drivers to never hook their thumbs on the wheel since when those front wheels went into a rut you just gently apply brakes (already moving slow since it's rough dirt) and let go of the wheel 'cus it's going to turn fast over to the lock instantly and thumbs in the way would not end up well....

  • Retrorockit
    commented on 's reply
    I agree about riding off road. In my case it was driving on 4 wheels. But it teaches you many things you can't learn otherwise. As far as F1 goes, a french F1 driver tried his hand at rallying. First day out he had 2 broken thumbs.No one told him don't hook your thumbs through the steering wheel spokes when offroad driving.

  • tklop
    commented on 's reply
    Very well said, AZguy.

    Getting to know your machine is everything--practicing until you're "wearing your machine"... You're exactly right.

    Also totally agree. Even if someone has a street machine... Definitely--get it out on the loose stuff--see how it feels when traction is compromised--when turning, when braking--over, and over, and over... Until you're "wearing" it.

    Words of wisdom--that can save your life.

    Also, not everybody is a forumula-one race-car driver (even though many people do overestimate thier own skills in such absurd ways)... We've all seen sad stores of people who've bought a lot more machine than they can handle... Sometimes it can be helpful to operate a machine whose limits are obvious, clear and well-defined.

    My first car was like that. It was a 48 horsepower VW Rabbit diesel. No power at all, but boy could that little thing zip through the twists! I learned exactly what that car could and could not do--and I learned to "wear" it well. I've owned many cars since then--and driven many others... And to this day, that was still the most fun car I have ever driven!

    All the best, AZguy!
    Last edited by tklop; 09-07-2019, 11:23 AM.

  • AZguy
    replied
    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

    Leave a comment:


  • tklop
    commented on 's reply
    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!

  • Defjr333
    replied
    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.

    Leave a comment:


  • Retrorockit
    commented on 's reply
    Brake balance aside from weather, and surface differences, uphill or downhill braking are seriously different also.

  • tklop
    commented on 's reply
    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, 03:01 AM.

  • Defjr333
    replied
    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.

    Leave a comment:


  • Retrorockit
    replied
    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.

    Leave a comment:


  • Defjr333
    replied
    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.

    Leave a comment:


  • Retrorockit
    replied
    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.

    Leave a comment:


  • JPLabs
    commented on 's reply
    Good insights, thanks!

  • tklop
    commented on 's reply
    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, 03:10 PM.
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