07 Brakes have a mind of their own

[MartyA]

No kidding, one time last fall and 2 times since spring, after my ECU replacement, my brakes have suddenly come on. It starts with a feeling like the bike is surging, then it starts to slow down, I give it more throttle but there is no response, then the brakes come on hard and it stops. I grab throttle and clutch and nothing happens, it just stops. The entire event takes about 3-4 seconds. The last second is the hardest stop, like a panic stop from about 15-20 MPH

The first time it happened was around 14,000 miles I was thinking the ignition was cut off, it felt like that - you know, sudden deceleration while the bike is in gear. As the bike slowed hard it kicked once just as it stopped. The first time it surprised me and I was more worried about getting off the road, so I probaby had the clutch out and the engine was probably running. After the bike stopped I turned the key off then on (thinking of what I read here about the bad ECU) and it started fine and went another 4,000 miles and 6 months of winter storage before it happened again.

The next time it happened, around 18,000 miles, I tried to pay attention to the status of the ignition and engine and everything else. I did notice that the lights on the dash stayed on, grabbing the clutch did not change the rate of deceleration, and blipping the throttle with the clutch out didn't speed up the bike nor with the clutch in did it appear to rev the engine. This is after the ECU replacement.

This last time, around 23,000 miles I watched again as best as I could as the bike suddenly began to stop and noticed the brake lever was pulled in about half way and loose - I was able to move it out to the normal position with my finger and it felt like it was not connected to anything. If it was a cable I would say if felt like the cable broke. As soon as the bike stopped the brake lever popped out into its proper position and worked fine right away. This time I didn't turn the ignition off, just pulled away from the edge of the road and no problems.

On all 3 occasions I was riding down the road and had not used the brakes for some time and the road was flat. The first time was at low altitude, in a 35 MPH zone just moving along with traffic, the second time was near my house at 2,000 ft in a 45 MPH zone no traffic, and the third time last week was at about 3,000 feet at about 70MPH during some spirited corner carving.

Each time this is how it appears:

The bike starts to slow down, so I give some throttle and expect the bike to accelerate.

The bike continues to slow down, no amount of throttle changes anything.

The brakes come on progressively harder and slows harder until it is almost locked up. I think the ABS prevents the total lockup, but the hardest part of the stop is at low speed.

This takes about 3-4 seconds after the initial feeling of slowing.

I was in for 20,000 mile maintenance at the dealer and told him about the sudden stopping and he just shrugged. At that time I suspeced the ignition, and he did change the ECU. If I cannot repeat it for him he has no answers. Now I don't know what to suspect, and this guy is not much good for anything more than spark plugs and tires anyway. I am going in for the 24,000 mile maintenance and don't know what to tell him.

The only electric mod I have is a Starcom 1 connected to the tail light. Stock ignition, exhaust, headlights, etc.

Any ideas?

 

[SkooterG]

Dude. Your FJR is possessed.

One thing you said didn't make sense to me - during one of your episodes you said with the clutch pulled in and when you applied throttle, the engine did not rev up? Was it still running/idling? This doesn't make sense. As much as you think it's the brakes, I can't see any way that's possible. There is nothing on the bike that can activate the brakes. Only the brake lever or pedal can do that.

 

[v65]

I am going in for the 24,000 mile maintenance and don't know what to tell him.

The name of your new dealer, seriously. You mentioned the ABS, is the ABS pulsating when this happens?

 

[donaldb]

I'm w/skoot on this one.

trade that sucker in.

 

[artistonFJR]

Just to be sure, ... the clutch is the one on the LEFT side... 'cause if you were squeezing the lever on the RIGHT side this whole thing makes sense and I can fix it for you immediately... otherwise I am gonna be paranoid... my bike is from the same '07 litter as yours, and the only problem I am having is getting the SOB into first gear at the occasional stoplight! But random stopping is not an issue and one I hope I never face. Get to a real Yammie shop and declare a safety emergency! They gotta listen if you call YamHQ, don't they?

C

 

[RAVENRIDER]

I would not ride that bike at all. With all the usual hazards of the road out there, this is just too dangerous. I think you need to be a bit more forceful with the dealer. I know I would. Good luck!

 

[JasonB]

Is your right foot a lot bigger than your left?

Other than being smart assed, can't help you a bit...

 

[FJR1300Mark]

What happens after you have one of these events?

Can you put it into gear and ride away? do you have to let it cool off first?

Can you push the bike at all after a forced stop?

What do the pads and rotors look like?

I'll get some pulsing of the abs sometimes when I don't think it needs it, but the brakes and abs have worked great.

Interested in hearing the followup.

thanks for the post.

 

[motorcycle-ed]

Sounds something like a problem I had on my ST1100 ABS bike once. I was riding down the road first trip after a tire change (did you have a tire change just before these events?) and the bike felt sluggish, requiring more and more throttle to maintain speed. I though a rear tire was flat, so i stopped. Smoke coming from rear brakes and the rotor was hot as hell. However, unlike your problem, the bike still had the brakes applied...hard. I waited for 15 minutes for the mess to cool off and presto!!!!!!!!!! The rear wheel would turn just fine. I rode it back home slowly and took off the brakes and found the spring plate mis-placed, causing the pad to drag. The dragging caused heat and the heat expanded the brake fluid apparently and applied the brakes. I fixed it all and bled the system, which had air in it????? It never did it again. The brake lever never did that trick yours did though.

Ed

 

[DailyCommuter]

I was thinking the same thing, air in the brake lines or have the brake lines themselves been moved in any way, like near a gray source. However the intervals between occurances seem to long to be that. If love to know when it gets figured out. Did you buy it new, if it was used did the previous owner change the brake fluid, maybe wrong type? Serious issue hope you get it squared away soon. Keep us posted.

 

[fhaze]

Strange indeed, my first thought is what is your right foot doing when this happens? slight drag on the pedal might heat up fluid eventually?

Drain and Flush all brake fluids.

Removed pads, actuate the calipers, lube, and replace everything.

Double check brake line routing, look for wear indicators.

If all that fails. Call a priest and Exercise The Demons!

 

[jjsC6]

A lot of things could be going on as has been questioned in posts above. But most of the suggestions don't take into account that he says the brake lever is moving in on it's own as well.

The ONLY possible answer can be tied to the ABS. Nothing else in the system can be applying brakes AND the lever moving without rider activation. I'd check the ABS sensors and make sure that the ABS "hub" that mounts over the axle is properly lined up. There is a notch that has to be lined up properly to keep the ABS sensor from rotating inadvertantly. There could be other ABS issues as well, I'm sure.

 

[SkooterG]

The ABS can't 'apply' the brakes either. All it can do is modulate pressure that has already been applied by another outside influence.

If this is NOT a case of some weird operator error, or if it is not demonic possession, than it's got to be some weird air in the system.

Bleed, bleed, bleed them brakes!!!!

 

[El Toro]

Most important bit of advice: Park the bike until you get this resolved. It is a big time safety issue.

Second most important bit of advice: You need to be yelling at Yamaha. A dealer that shrugs off this sort of complaint is not doing them any favors. If you have a written record that you asked them to check this out and they blew you off, they've got to have some liability if things go wrong and there are damages.

Trivial unimportant anecdote: I had a 1992 XJ600S (Seca II) and the front brake got to where it would not release the pressure on the caliper reliably. Pressure would build in each time you used the front brake, and after a few uses, it would be tight enough to lock up.

I took the caliper apart. Pistons seemed OK. They moved with minimal effort and didn't look too bad. No leaks. I put it back together and had a lot of trouble bleeding it. I finally used a power bleeder, and after I got a good "pedal," it worked great for about 15 applications of the front brake, after which it locked up again.

It looked to me like there was a problem with a check valve in the master cylinder. No rebuild kits to be had. So I bought a new aftermarket master cylinder, new brake line (since it was overdue), rebuilt caliper and replaced the pads (for good measure since I was there anyway), and replaced the fluid. Rotor was within spec. It bled easily without resorting to a power bleeder, and it worked just fine with no more problems.

 

[MartyA]

Appreciate all the responses. I bought the bike new April 07. I have had 4 front tires and 8 rear tires since new last spring, all but one done by me and my buddy in his garage, so I have had lots of opportunity to mess that ABS up. The last occurrence of this brake lockup was last week at about the 3,000 mile point of a 4,000 mile New England / Canada trip.

I am thinking ABS is somehow activating the brakes. If, and I say if, I had just applied the brakes and they did not return I could suspect the splooge hole in the master cylinder was plugged, but if that splooge hole is plugged it usually stays plugged until you clean it out.

In every case the bike was perfectly fine after. No brake fade or harder brake feel or anything.

The first time was a little scary and I was a little tense so any info for that event would be sketchy. This was before the ECU change and I was thinking at that time the ECU was screwing up again but it was the brakes. I did turn the key off and back on then, ECU habit, and don't recall if the engine was running.

The second time I paid a little more attention, but as it was happening I was thinking fuel shortage first, and I tried to add throttle with no result, and then pulled in the clutch thinking I would not stall the engine, then tried the throttle again. I think I left the clutch out because I remember the bike kinda jumped once as it came to a stop, and then I realized the engine was off. I am assuming the engine was running before I stalled it by leaving the clutch out.

The third time, last week, I recognized what was happening and tried to assess what was what in a couple of seconds. That was when I noticed the brake lever was in a little and it was loose when I poked at it. This time the engine did not stall, and I heard the brake lever pop back out as soon as the bike stopped rolling, and I just drove away.

This all happens in a moment so I can't reliably state all of the conditions of the bike. Try braking and as you slow add more brake and then around 20 MPH try slamming on the brakes right to a stop and you will feel what I am feeling.

I think it happens all or nothing. I am getting 42 MPG fully loaded 2-up so I don't think I am dragging pads.

jjs, if the ABS sensor was not aligned as you describe, would that cause this to happen intermittantly, or all the time?

Jason both feet are big, but I am sure I am not resting on the rear brake.

FJRMark pad and rotors are not discolored, and pads have lots of life left, not worn down yet. Don't recall feeling any pulsing.

Raven the stop is somewhat controlled and I am not too worried. My concern would be if it happend on a bridge with no pull-off area. But in all cases it took only a few seconds to get under way again.

I have kept to the 4,000 mile intervals of maintenance with the same dealer. My book is not handy but is brake fluid service in there somewhere before 24,000?

I have read about error codes here but can't find anything on them. If the ABS was messing with me would there be some error code? Where do I find it and how?

Exorcism next? If I find anything I'll report. If the dealer finds anything I'll get over the sudden rush of blood to my brain and I'll throw a party. I don't know how to contact Mama Yamma and what would I tell them anyway?

Thanks for all the replies.

El Toro I was typing when you replied. Going to the dealer Tues will get it on record this time. Sounds like your splooge hole was plugged on your Seca.

Skooter, I am not totally familar with ABS pumps. My former company helped design the magnetic sensors for the first trial devices so I know about the sensor technology. Doesn't the pump actually pump liquid, or pressurise or something? Could it turn on and stay on as some form of fault, then stop when the bike wheel stops spinning? Just thinking out loud. But regardless I agree I will have the fluid replace this time.

 

[madmike2]

The third time, last week, I recognized what was happening and tried to assess what was what in a couple of seconds. That was when I noticed the brake lever was in a little and it was loose when I poked at it. This time the engine did not stall, and I heard the brake lever pop back out as soon as the bike stopped rolling, and I just drove away.

Hmmmmm....brake "lever" popped? Have the pivot points been lubricated? Have you pulled the pivot screws to check for cracks or wear on the brake lever? Has the bike ever "toppled" and slightly bent the brake lever? Is it possible that if you haven't changed the fluid the cylinder bores are dirty enough that the piston doesn't return? That would be a maintenance issue to take up with whoever does your PM service.

jjs, if the ABS sensor was not aligned as you describe, would that cause this to happen intermittantly, or all the time?Jason both feet are big, but I am sure I am not resting on the rear brake.

FJRMark pad and rotors are not discolored, and pads have lots of life left, not worn down yet. Don't recall feeling any pulsing.

Raven the stop is somewhat controlled and I am not too worried. My concern would be if it happend on a bridge with no pull-off area. But in all cases it took only a few seconds to get under way again.

First you are talking about the brake lever, then you mention your feet on the brake pedal...which brake is locking up? Even linked brakes only apply a percentage of front brake force.

Skooter, I am not totally familiar with ABS pumps. My former company helped design the magnetic sensors for the first trial devices so I know about the sensor technology. Doesn't the pump actually pump liquid, or pressurize or something? Could it turn on and stay on as some form of fault, then stop when the bike wheel stops spinning? Just thinking out loud. But regardless I agree I will have the fluid replace this time.

Even if the ABS motor came on, it shouldn't pressurize the system. The system has to be pressurized by the brake lever or brake pedal.

 

[MartyA]

Hi Mike. Looking more and more like a fluid problem, except the 1st time was when the bike was only a few months old. And I can't tell which brake is on, or which one is on more, I was assuming both. Understand this happened all 3 times when I was just riding down the road. I was not just leaving an intersection, not pulling away from a stop, not slowing for traffic, just riding along on the road. And no, as far as I know never dropped. There are a couple of scratches on the right side bag *could* be from a bump in a parking lot but no scarring on the lever.

I'll check that lever out more closely tomorrow. Good thought.

 

[madmike2]

I'll check that lever out more closely tomorrow. Good thought.

You should also check the brake pedal pivot. They are known for needing lubrication and cause the pedal to stick and not release completely.

I only mention the lube on the brake lever because I swapped out another owners levers for Pazzos @ WFO-6 and his levers on an '03 didn't look like it had ever been cleaned and lubed. They were "sticky" enough there was resistance to pulling them out of the pivot saddle once I pulled the pivot screws.

I HOPE it's that easy....and change the fluid! You might consider flushing the system to get all the old fluid out. I use a "Mighty Vac" and that works well for me (In fact, one of the maintenance projects this weekend inpreparation for NAFO.).

 

[El Toro]

El Toro I was typing when you replied. Going to the dealer Tues will get it on record this time. Sounds like your splooge hole was plugged on your Seca.

Man, you don't know the half of it. When I peeled the rubber boot away from the fitting at the master cylinder, it was not leaking, but was encrusted with what looked like stop leak residue.

The master cylinder itself was full of floaters and ghizz.

Rather than try to clean it out, I just replaced the whole thing. What a mess.

I'd bet a buck that somebody who knows a lot more than the engineers at Yamaha decided that it would be OK to fix a leaking brake line by putting in some stop leak. As is so often the case, the problems showed up later. Since everything worked and the leak stopped after their experiment, they're probably on another forum right now telling folks how clever they were to fix the problem. " You don't need to replace a leaking brake line union. Just use stop leak. I've done it countless times. Just be sure to use the Amsoil stop leak. That's what we use in the big rigs, and if it'll stop a leak there, it'll sure stop a leak in a motorcycle."