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Discussion Starter #1
Hello, I've been riding my 900 almost every day since I got it about 9 months ago. A couple of times I've had to do emergency stops, once while traveling at about 50 mph along a straight road and once while traveling pretty slow after turning a corner. In both cases my rear tire slid out to the side, not enough to cause me to lose control but enough to make me think I'm doing something wrong.

My initial thought was that I'm not hitting the back brake hard enough, i.e., if the back wheel keeps spinning when the front stops maybe it's likely to go off to the side. However, after looking at other explanations it seems like maybe the issue could be caused by the opposite problem, i.e. too much brake at the rear tire causing it to skid. Both times the rear tire (but not the front) did skid. Any thoughts?
 

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Too on much brake on the back tire will cause you to have it slide out, especially if you lock the tire up. Try reading Proficient Motorcycling: The Ultimate Guide to Riding Well by David Hough. It explains so much about the dynamics/balance of motorcycles. Alot of it seems like common sense, but it's the kind of common sense where you think "oh ya, that makes sense, but I never would have thought of that" haha. I am on page 200...

Sent from Motorcycle.com Free App
 

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The back tire won't skid unless it loses traction, which can be caused by too much rear brake (or too much throttle at the wrong time, but your question is about braking). It just comes with practice, knowing how hard you can mash the rear brake without locking it.

A common result of locking/skidding the rear tire is a highside crash. If the back tire skids, when it regains traction, if it isn't aligned with the front tire and moving straight forward, off you go, over the "high side" of the bars. Granted, if it's just a momentary thing and you can keep the bike under control with the wheels aligned, that probably won't happen, but a highside is pretty gruesome.

Here's a nasty example of a highside.

Have you taken an MSF course?
 

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Discussion Starter #4
Braking

Thanks guys. Yes, I took the safety course when I first started, but apparently I need a "refresher" on braking. I'll check out that book if I can find a copy. Is it available online?
 

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When you start to slow down you have the weight of the bike shift to the front wheel which takes some pressure off the rear wheel. It just takes some practice. Squeeze (not grab) the front brake steady and push the rear brake steady, when you feel the rear wheel start to skid ease off the brake until you get traction again.
 

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It is recommended in the Safety Course and the book "Proficient Motorcycling" that if the rear tire has lost traction and is skidding while breaking that you DO NOT release the brake.. (FYI, a sliding tires always wants to lead, be it Car, Semi or Motorcycle)
 

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A couple of thoughts.

One, there are times lack of available stopping "room" might make you want to get the rear "loose", in part to slow, in part to steer around an object.

Two, be wary of this, as there is a good chance the engine will stall, as timing of down shift/clutch might not perfectly match in this panic situation.

I've done this, wasn't a planned thing. Nomads's don't stop really quick.....
 

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BrewinProf,

I had that exact same bike and the exact same situation about a month ago. A hard stop on the interstate with almost not enough room in front of me. I thought the same things. I came to the same conclusion as you and the others here: too much rear brake and possibly not enough front. My back tire fishtailed. I stayed on the rear brake til I got down to about 25 mph and then let both brakes go. I was then able to re-apply both brakes with traction and come to a safe stop. SCARY AS SHIT.

What I can tell you as a former vulcan 900 owner is that the rear brakes on those bikes are weak. And you need to know that so you can adjust your riding style. I have test driven other bikes and just traded in on a Road Star. Every other single bike I've ridden has rear brake performance that GREATLY outperforms the vulcan 900.
 

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Knowing the limitations of your brakes is a good thing. Most riders don't, and therefore can never achieve maximum braking efficiency in an emergency situation.
The advent of ABS has helped the average rider stop a lot more safely in an emergency situation, but there is still no substitute for knowing your bike, and its limits.
One of the things I used to demonstrate was the stopping distances using rear brake only, then front brake only then both brakes together, braking as hard as possible each time, from a brake marker, at the same speed, just on the limit of traction. (This was in the days before ABS and Linked brakes).
Braking with both brakes together always gives the shortest distance.

The reason I mention this is to go on to say that most riders I have had the pleasure of helping don't realise just how hard you can squeeze the front brake lever before anything bad happens, and just how easy it is to lock up the rear.

Before I was qualified to teach one of the things on the course was to find the limits of braking, individually front and rear, and to recover from that to bring the bike to a controlled stop. Now I don't advocate trying that on a heavy machine like a Voyager or similar, but it was a valuable learning experience for me, if a little nerve jarring the first few times.

If the rear is stepping out sideways under emergency braking, sounds like you already know the limits there. I would think that a little more front brake and a little less rear would be better. However, remember it is more unlikely that you will cause the front to lock, but a much harder situation to recover from, especially if the bike is leant over even a little, which brings me to my final point (sorry for rambling on) only brake really firm when travelling in a straight line, even with ABS.
 

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I only have less than 1000 miles under my belt on a motorcycle, But I have raced BMX and now into mountain biking. I know that mountain bikes and motorcycles are apples and oranges, but I use a lot of front brake on my disc brake mountain bike and find it comfortable to use the front brake a lot more than the back on my 500. Is this a bad thing? I have practiced in a parking lot making hard stops with both by them selves and both together.
 

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I only have less than 1000 miles under my belt on a motorcycle, But I have raced BMX and now into mountain biking. I know that mountain bikes and motorcycles are apples and oranges, but I use a lot of front brake on my disc brake mountain bike and find it comfortable to use the front brake a lot more than the back on my 500. Is this a bad thing? I have practiced in a parking lot making hard stops with both by them selves and both together.
The best and most efficient way to brake is to use both brakes together. Even when only a small reduction in speed is required when engine braking alone is not enough, however tempting it may be just to tickle the front or rear brake only, it's best to use front and rear together, otherwise it becomes a habit to brake that way all the time, and then both brakes together only get used when you really need to anchor up.
Also braking using both brakes evenly distributes brake wear. No quicker way to knock out a set of rear pads than by using the least efficient brake on the bike on it's own, all the time.
So to answer your question, it's not a bad thing to use the front a lot more, better the front than the rear, but better still to use both together. 70% front pressure and 30% rear, or in other words about twice as much pressure on the front brake that the back.

Old Skool thinking for road riding was to be able to ride a twisty road 'on the throttle' without using the brakes at all. Looking a long way ahead and reading the road, adjusting your speed by easing off the throttle and allowing the bike to slow down by engine braking. Not a particularly quick way to ride, but very satisfying when you get it right, and it saves wear and tear. (And I don't mean dumping gears to slow down.)
 

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I only have less than 1000 miles under my belt on a motorcycle, But I have raced BMX and now into mountain biking. I know that mountain bikes and motorcycles are apples and oranges, but I use a lot of front brake on my disc brake mountain bike and find it comfortable to use the front brake a lot more than the back on my 500. Is this a bad thing? I have practiced in a parking lot making hard stops with both by them selves and both together.
I've been riding a year but it seems to me how much of each brake to apply and when is the most difficult thing to judge correctly. The front and rear brakes change your handling in different ways. In slow maneuvers I find using the rear brake only helps tremendously.
 

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I've been riding a year but it seems to me how much of each brake to apply and when is the most difficult thing to judge correctly. The front and rear brakes change your handling in different ways. In slow maneuvers I find using the rear brake only helps tremendously.
Yes this is absolutely true, and shame on me for not mentioning it. :eek:

If you are doing any slow manoeuvring at 10 mph or less, then the rear brake can greatly increase your manoeuvring skills. It's kind of a balancing act between rear brake and clutch and throttle.

Always remember to look where you want the bike to go, and not at the ground in front of the front wheel. If I intend to do a U turn or something similar I tend to scan the area that I'm going to go over quickly for gravel and such, and then keep my vision up and if necessary turn my head and look over my shoulder in the direction that I want the bike to go.

The Voyager linked brakes don't operate below 12mph for this very technique.
 

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Yes this is absolutely true, and shame on me for not mentioning it. :eek:

If you are doing any slow manoeuvring at 10 mph or less, then the rear brake can greatly increase your manoeuvring skills. It's kind of a balancing act between rear brake and clutch and throttle.

Always remember to look where you want the bike to go, and not at the ground in front of the front wheel. If I intend to do a U turn or something similar I tend to scan the area that I'm going to go over quickly for gravel and such, and then keep my vision up and if necessary turn my head and look over my shoulder in the direction that I want the bike to go.

The Voyager linked brakes don't operate below 12mph for this very technique.
How do the Voyager Linked brakes work. If you apply the brakes the same no matter if you squeeze the front brake or rear peddle, or will the back end still set down a little more if you hit the rear brake and the front drop some when you hit the front? I don't know if I am asking my question properly.
 

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How do the Voyager Linked brakes work. If you apply the brakes the same no matter if you squeeze the front brake or rear peddle, or will the back end still set down a little more if you hit the rear brake and the front drop some when you hit the front? I don't know if I am asking my question properly.
The literature a couple of years ago said something about a "portion" of braking pressure is applied to the other brake.

Looking at my front brake lines last night (wanting longer braided lines); it looks like only one of my front calipers is connected to the K-act pump.--Edit: Checked the fittings in diagram--I misidentified a part. Both calipers are connected to the pump.

If you get going at a pretty good clip and brake hard with only the front and then do the same thing with only the rear; you will feel a difference. So, you can still set your contact patch by using the rear first.

I think there is an algorithm in the ECU that calculates speed vs braking pressure. So that a hard brake will apply a ratio closer to 70/30 while a light brake will be less noticeable.

Scott
 

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The literature a couple of years ago said something about a "portion" of braking pressure is applied to the other brake.

Looking at my front brake lines last night (wanting longer braided lines); it looks like only one of my front calipers is connected to the K-act pump.

If you get going at a pretty good clip and brake hard with only the front and then do the same thing with only the rear; you will feel a difference. So, you can still set your contact patch by using the rear first.

I think there is an algorithm in the ECU that calculates speed vs braking pressure. So that a hard brake will apply a ratio closer to 70/30 while a light brake will be less noticeable.

Scott
Its an odd feeling to get used to. I caught my self doing things and not getting the results I expected out of the HD I got now. I was bad with the V2K to let the engine brake the rear wheel and ease on the front, then when the engine calmed down then I would get on the rear to pick up where the engine would let off. Well doing this on the HD cause me to brake harder than I was wanting to a few times. So what I started doing was when I got on the rear, I would have to ease off the front just a little to keep slowing down smooth. It's not bad, just different. Also this is my first bike with linked brakes and ABS.
 

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Its an odd feeling to get used to. I caught my self doing things and not getting the results I expected out of the HD I got now. I was bad with the V2K to let the engine brake the rear wheel and ease on the front, then when the engine calmed down then I would get on the rear to pick up where the engine would let off. Well doing this on the HD cause me to brake harder than I was wanting to a few times. So what I started doing was when I got on the rear, I would have to ease off the front just a little to keep slowing down smooth. It's not bad, just different. Also this is my first bike with linked brakes and ABS.
I've only hit the ABS on the rear once in real world riding. Felt strange but not scary. I've hit the front during parking lot practice; you gotta really hammer that thing.

With the linked brakes, I've gotten bad about only setting my foot on my rear pedal for most of my braking.
I know it produces muscle memory; but I really should play with how it affects the suspension more.

I think the weight location of these things really changes the braking dynamics too. My 900 didn't have near as good of brakes as my VV, but the bike felt "tamer" under hard braking.

Scott
 

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I find it strange that you say the bike wanted to come around on you in a straight line. I have never had my bike do that and I practice emergency braking once in a while...

So far, I have only had one real emergency brake test. I had a woman walk out into the road and never looked up to see me coming and it was lightly raining. The rear wheel locked up on me but I kept it locked and squeezed down the front brake to get the Vulcan 800 stopped. It wasn't close by any means but it sure reinforced that you don't stop on a dime and on wet roads you don't stop on a dollars worth of dimes!
 
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