| Author | Message | ||
     Figorvonbuellingham |
I'm lookin at a CR. I rode it and went to stop and the rear brake isn't working right it just comes to a gentle stop when I was standing on it. My old CR would have been locked up. Is this a common issue? Owner didn't know anyhing about it he's just flipping the.bike. | ||
| Froggy |
Thats what happens if the brake isn't used much. Either crap builds up on the rotor, or the pads were never broken in, but after using it a bit it will return to normal. It happened to me after buying both of mine brand new, after a few days it would work fine. | ||
| Jimustanguitar |
How much rear brake pressure are you guys actually applying? I don't feel like I'm pressing on it any harder than my hand is squeezing the lever... Always trying to keep the 60/40 rule in mind. How does one tell if they're braking evenly? | ||
| Nuts4mc |
Figor, like Foggy sez sometimes it's due to lack of use - 1) the exhaust is pointed at the disk brake which doesn't help - it dirty's up and heat's up the area. ( try and buy or make some turn outs if you run the stock exhaust) 2) the master cylinder has a history of seizing (lack of use, the brake fluid attracts water, the cylinder gets corroded and stops moving)try flushing/bleeding the rear brake...it'll help. Mustangjim - as the front brake is applied the weight transfers from rear to front ...the rear wheel goes "light" making it prone to locking up (lack of traction)....have you ever locked up the rear wheel while heavy braking in a straight line?...go out and practice panic stops in a straight line to learn the point of lock up...as it will change based on temperature and traction..the front brake on this bike ( as it is with many hi performance brake pads)is better hot than cold. | ||
| Jdugger |
> How does one tell if they're braking evenly? Is is OK for me to suggest this is not something you should worry about at all? Using an expert rider, the stopping distance achieved with the front brake only vs. front and back brake together is almost the same. As mentioned above, at optimal braking, the rear wheel of the motorcycle is just barely touching the pavement, so there's really no additional value in the rear brake for slowing the bike. We tend to stress this a lot when teaching on the track, because as the rider gets just a little bit better and carries a little more speed, the rear brake can be a source of a lot of crashes. It becomes so easy to lock the wheel up and accidentally get the bike sideways. It takes tremendous skill to use the rear brake effectively when using the front brake to slow the bike quickly. But not using the front brake for 95%+ of your braking means you are doing a lot of unnecessary coasting or taking way too long to get the bike slowed down. In general, the rear brake is good for a lot of things, but slowing the bike isn't one of them. | ||
| Sir_wadsalot |
Rear brakes are for parking lot maneuvers & gravel....if your back wheel is still on the ground in a panic stop, you're not doing it right. That's what guys mean by "I laid it down"....they mean "I panicked and stabbed the rear brake and the rear came around and I crashed."...that's what they mean to say. I wouldn't even consider the rear brake in the decision, other than maybe make him take a little off the price. I assume with any used bike I buy that the brakes need a complete teardown and fluid change at any rate. Somewhere in that process the problem will be discovered & worked out. I didn't do that when i bought my 1125R, because it only had 2000 miles on it, thus I just thought it had crappy brakes. After maintenance when the wheels were pulled (and Jdugger's advice)...it has great brakes. Most likely they're just glazed from lack of hard use and the exhaust blowing on them, or need a bleeding. 100 grit will cure the glazing problem. Assume the front rotor needs a good scuffing as well. | ||
| Figorvonbuellingham |
Yeh I talked to both previous owners and both say bike has been rode very little recently due to health issues. So what froggy says makes sense. I was test ridding the hike so I was checking rear brake individual from the front and there just wasn't any grab. I then litteraly stood on the rear brake and it just gently came to a stop when it should have been a full on lock up. I'm going to look at it again tomorrow after it get a new battery and ill ride it again. | ||
| Jimustanguitar |
On clean pavement I've done some hard stops, yes. I can tell when the rear tire is right on the cusp of locking up, there's just this gut feeling that I get about the physics of the tires and pavement. It feels kind of like how drivers who're used to the snow get a knack for it. But anyway, during normal street riding (commuting stop light to stop light, not the dragon tail or anything technical) the consensus is that using the rear brake "properly" is not as critical? I guess I'm used to old bikes (like 30 year old bikes) that have undersized rotors and single piston calipers and need some finesse on the rear brake to stop smoothly... Glad I'm riding modern technology now  | ||
| Jdugger |
Jim... I personally believe the rear brake does not have much place in slowing the motorcycle. As such, the "proper" use of the rear brake is not at all for slowing down, but certainly for things like keeping the bike stationary on a hill waiting for a green light. | ||
| Sprintst |
Rear brake? Lol Why would you want one, for the most part? | ||
| Dannybuell |
The tube frame riders complained about this in the early days. Racing bikes use the rear brake for 'trail braking', a maneuver that will make the bike turn in better if applied near the apex of the turn. In the words of Erik Buell 'this is by design'. | ||
| Jdugger |
> Racing bikes use the rear brake for 'trail braking', > a maneuver that will make the bike turn in > better if applied near the apex of the turn. Danny, "trail braking" is short for "trailing off the brake as approaching the apex". I've heard your understanding of trail braking before, assuming that trail means "trailing wheel", but it does not. Generally, trail braking is done with the front brake exclusively. The key is to turn in under hard brake pressure and slowly trail it off as one approaches the apex. Adding brake pressure once already in the turn asks an awful lot of the front tire. Some additional reading: http://en.wikipedia.org/wiki/Trail_braking | ||
| Andros |
Mine came like that new. New fluid and proper non HD pads made it lock up just by looking at it. | ||
| Figorvonbuellingham |
I got the bike today and rode it about half hour bringing it home. Rear brake seemed to be working better by the time I got it home. Now time to throw a new stator and rotor at it. Yike$$$$ | ||
| Dannybuell |
thx Jdugger! I use my front brakes as you and your link explained, I take that part for granted. If the front isn't turning in enough using the rear at the apex seems increases the turn in for me. what is that called then? | ||
| Jdugger |
More braking? I honestly don't know. In racing, we generally crush the front pretty hard on the front brake and use the dive (which shortens rake/trail) to initiate the turn-in. As we approach the apex, we are increasing lean angle while giving back brake pressure. This sequence is especially obvious in double apex corners where it's necessary to maintain position. I would need to ride with you so see what you are doing. It's possible you are just slowing the bike a little, which for the same lean angle will tighten the corner a bit. At street speeds, that's fine, but be careful as you pick up the pace since you are adding load to the front tire once already leaned over... can cause a low-side. Generally, the rule of thumb is to heavily load the tire FIRST, then lean in while slowly trailing off the brake, adding lean angle as you reduce brake pressure. If the front pushes, the standard corrective measure is to gently return to throttle. There are some much better/faster racers than me here that may have other input. | ||
| D_adams |
You know you need this to go with it.  | ||
| Georgehitch17 |
such a sick exhaust! @D_Adams if only I didn't just buy a new track weapon! | ||
| Skntpig |
Danny, I am probably not faster than Jdugger but I do agree with his explanation of trail braking. Most of the time you should be applying throttle at the apex and not adjusting your corner with the rear brake. Then again I could be misunderstanding you. | ||
| Dannybuell |
I brake hard just before the apex, if i'm not getting the apex like I want at that point I give the rear brake a push and then the apex is attainable. | ||
| Sir_wadsalot |
Dugger's being polite, but I'll bite the bullet and be the dickhead here (just remember, it's out of love)- if you're "braking hard" just before apex, you're both braking and cornering incorrectly. In the first edition of Twist of the Wrist, you got the basic rule, brake early, before turn in, get back on the gas and roll through the turn. No brakes through the curve, trail braking was the devil. At Pridmore's STAR school, for one, trail braking is taught like it's the holy grail. It's not a beginner technique, and it's largely a matter of style. All the pros do it though, so there must be something to it. In Kieth Code's most recent writings he's come to embrace the technique...you trail the brakes through the curve if necessary, you should still be on throttle through the curve, add a little brake to pull the line tighter if you're too hot, that's about it. If you're in the proper gear you can do the same with the motor. More gas runs wide, less pulls you in. I never used to do it, but find it works on the Buell because the front end feel is so good. Some Gods among men and supermoto guys will take a reverse line, lock the rear brake to swing out the rear and get back on gas while traction is broken in order to slide through a turn at opposite lock....but that's not what we're talkin' about here. Nothing hurts your pride more than being knee down on your literbike, and then have a guy on a 450 single slide by you sideways like you're standing still...and then wheelie out to boot! Some guys will add a dab of rear brake at the very end of their brakeing, just before turn in and rolling on, to "settle the chassis". I personally don't believe in it, but it's a valid technique. That said, at no point in a turn should you ever "brake hard". This is what fast riders call "parking it" in a curve, and at best throws your own rythem off, at worst upsets the chassis. If you haven't read "Twist", get any of them really, but don't bother with "Soft Science of Motorcycle Racing" until you've been on track, it's a bit abstract with lots of drills you can't really do on the street. In the meantime, take an hour and a half and check this out- http://www.youtube.com/watch?v=bVWNinsmkAw It's hokey, but it touches on all this stuff....the animations and the slide rigs are priceless. No track instructor, video, book, or internet knowitall with three whole track days under his belt (like me) would ever advise anyone to "brake hard" in a turn. Consider this- If you're in a turn at a "proper" speed and lean angle, Braking hard or stabbing the rear is almost definately going to crash you. It's a chicken and egg thing. You're slowing down to make your line, but you only have the time & front grip to "brake hard" becuase your entry speed is too low in the first place. Chicken & egg....(on track, ideally) That's called "charging the turn". If you have to "stop hard" before you can hit your apex then you have gone in too hot. I do it on roads I don't know, everyone does...it't just a bad street habit you have to train yourself out of. That's the kind of thing that gets you crashed when your speeds increase, or a deer or slow moveing Harley jumps out in front of you. Try this- when you run up in a curve and hrake hard to hit your apex, go through it again and just slow down to where you don't have to brake. That's your line. Keep that line, add a little speed. Rinse & repeat. Smooth is fast....Dickhead out!  (Message edited by sir_wadsalot on September 30, 2013) | ||
| Jdugger |
> At Pridmore's STAR school, for one, trail > braking is taught like it's the holy grail. > It's not a beginner technique, and it's > largely a matter of style. All the pros do > it though, so there must be something to it. In many kinds of corners, it's the fastest way through, allowing the rider to maintain the highest average speed. In corners where the brake-first, tip-in, carry-the-gas-through would be faster, trail braking becomes an essential defensive technique. By carrying the higher speed into the corner until the apex, you gap riders using the brake-before-cornering technique. So, it traffic, there's two options: 1. Trail brake, or 2. Get Stuffed. | ||
| Dannybuell |
Great discussion! '... More gas runs wide, less pulls you in...' 'less pulls you in', I call that drop throttle oversteer. My96s1 and an 1125 with the stock ECM or an ECM without a dieseling idle air control will really pull you in! | ||
| Jdugger |
> I call that drop throttle oversteer You need to be very careful with this. What you are doing is transferring weight to the front end of the motorcycle, reducing rake and trail, and thus the bike steers more tightly for a given radius (lean angle) and speed. If you do it while already leaned over, you are asking an awful lot of that front tire. At street speeds, this is probably fine. You are probably a long ways from consuming the available traction of the front tire. As you learn to ride a little faster, this is a low-side prone move. It is much more advisable to load the front tire before turn-in, and slowly release the load (from braking) as you are increasing lean angle, thus maintaining the contact patch. To add front tire load while already leaned over is to hope for the best. I'm not saying it won't work -- as long as you don't overload the tire you are fine -- but it's not the optimal solution for front tire traction. One day, it will get you. Also, you have used these terms "drop throttle oversteer" and "dieseling" a few times before, and neither are actually what's going on. I think I've explained above why you feel the radius tighten when you cut the throttle. What you are trying to describe with "dieseling" is actually just engine braking. And, yes, it's quite a variable thing depending on motor type, fueling, rider skill, and so on. In general, at least for track purposes, too much engine braking is not a good thing. Remember back to the discussion of using mostly front brake. Engine braking really isn't anything more than rear brake. Excessive amounts of it will cause the rear end to step out ("backing it in") as the rider's skill on the front brake leads to consistently lofting the rear tire a bit. While backing it in can be useful, generally keeping the bike in-line is the fastest way around the track. | ||
| Dannybuell |
Street riding pretty much guarantees there will be some unfamiliar curves so a ten-tenths approach is never deliberate. I back off the throttle get my line and then lean it over. Sometimes I back off the throttle grab a ton of front brakes get my line and then lean it over. | ||
| Noobuel |
This is how I often do it, but it feels very awkward and unnatural, and like my utter lack of skill is showing.  | ||
| Jdugger |
Just be careful, Danny. What you are doing will ultimately ask more of the tire than it is capable of, and cause a crash. There are more graceful ways of managing available traction. | ||
| Dannybuell |
thx guys | ||
| Rpm4x4 |
I disagree with quite a few comments in this thread. Something I think that should be considered is we don't all only ride on a track. On the street I will argue that the rear brake is very important. I have been following this thread and have been thinking maybe I don't use enough front brake and/or too much rear. Today I was riding and came upon a construction zone that had changed drastically since the last time I was there. It was before sun up and I was going too fast for the amount of gravel. If I had grabbed a handful of front brake I'd have gone down for sure. Then later in the day I run a hard curve to a stop sign. It had road snakes recently put down. Rear brake was essential. | ||
| Sir_wadsalot |
To quote myself- "Rear brakes are for parking lot maneuvers & gravel." GRAVEL. And sand, and as Jdugger said, holding the bike on a hill. And if you're on a cruiser. Abnormal conditions, even on the street. What we're saying is that relying on the rear brake on a sportbike regularly, is eventually going to get you crossed up in a panic situation, on the most common of street riding scenerios...on pavement. You stab the rear brake with your foot (which is RETARDED compared to your right hand) while grabbing a handfull of front brake, shifting the weight off the rear, is going to cause a slide. A sliding tire cannot be controlled. @Dugger- I agree completely with your trail braking assesment, I just didn't try to impart it because I'm not that advanced with the technique. I can't do it, so I won't preach it, but you're right. That's also why there are so many front end slides in racing now, that's the extra edge everyone has to have at the top levels...higher entry speed. (Which is incidentally my weak point.) Some of the stuff you've said before about haveing the forks soft and whatnot goes totally against my own experience, your pic with the forks completely bottomed out...the stuff blows my mind....I'm just not at that level & can't comprehend and process what you're doing. My ridecraft is probably at early 90's level techniques! It seems to me there would be too much front end pitch going on for stability, but I can only guess that it in some way helps give the tfront tire a ....umm....buffer? For a bit of extra wiggle room for traction on the front tire for the trail braking? It's rare when I can't explain what I'm trying to say. Mind Blowing. As far as what was said about "drop throttle oversteer" being dangerous, I'm not talking about chopping the throttle mid turn, I'm talking about the mildest of throttle corrections...Code calls it "steer from the rear". A little more, a little less. Forks are evenly loaded the whole time if done correctly, chassis shouldn't ever be upset in the process. I will say again that I'm naturally trail braking to pull it in more than I used to, just due the the Buell's front end feel, but I won't really "know" until I test that theory on a track. That's why I mentioned the STAR school as opposed to the Cali Superbike School, to highlight differing techniques from valid sources.....and I think in recent years Code has gone over to your side of things with the trail braking, whereas it used to be him preaching against it and everyone else for it. I don't get a lot of track time but i read a lot.....even Kevin Schwantz has stopped preaching the "Don't brake until you see God" thing and has taken to teaching smooth trail braking at his school. (Message edited by sir_wadsalot on October 03, 2013) | ||
| Jdugger |
Keep in mind there have also been huge leaps in machine and tire technology, and it has changed what is the optimal combination of rider techniques over time. I doubt you could safely crush the front like we do today deep into the corner in Schwantz' era. I see those old bikes and I don't think I could wobble down the street on one, much less race like those guys did... | ||
| Jdugger |
> your pic with the forks completely bottomed out I love this shot! Turn 4 at NOLA, having just come off the brake...  |
