Intermittent loss of power at high speed

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Floridave

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The last couple days I've been having an issue with the FJR, hope I can get some ideas on what the issue is. I have about 55,000

miles on my 2007 AE and it's never missed a beat. It's been running great, gas mileage the same as always. Ridden 5 days a week,

not been sitting at all.

Yesterday evening after work when I cranked it to head home, it started, but died as I put on my gloves. Never does that.

It died twice more at 2 of my 4 stoplights to the highway. Again, it's NEVER done that.

On the 45 mile ride home, I had 4 incidents where the engine cut out, only for a second or two, a couple twists of the throttle

and it came back to life and I continued on. This is steady cruise at 70-80 mph, and it acts exactly like I just suddenly

close the throttle, for about a second or two, then I get it back. Not fun in after work traffic.

No loss of electrical power, no codes or lights on dash.

At home, I let it sit and idle a while, and it sat there an idled perfectly,

though I noticed the idle was around 8-900, so I bumped it to 1100.

I let it cool, went back out and started it again, seemed to start and run fine, I added some fuel injector cleaner, and rode it

to fill with gas. I had about 1/3 tank. Filled it with high octane (normally run 87). Rode about 15 miles and everything seemed fine.

On the way back in to work this morning, I had another 3 or 4 of these 'cutouts'. This is when I confirmed I wasn't seeing any codes

or lights flash, I don't lose electrical power ( my GPS would reset if it lost power even for a second). I could simulate the

exact feel of this by chopping the throttle.

I didn't have any low speed stall this morning with the idle speed bumped up, and I don't know if those

are related at all. I rode to work yesterday morning with NO issue at all. So both the dying at idle and high speed cutout

started yesterday after work. I reset gas mileage computer last night, and those numbers are perfectly normal after 60 miles of riding. When I got to work this morning, I let it sit and idle is fine, smooth.

On the way home last night, I was thinking fuel filter, bad gas, that type thing. But I know it's not that.

Any ideas of what would cause something like this? Just a sudden lose of engine power, like loss of fuel supply, but within

a second or two full return of power.

I am due for an oil change and plugs. And I'm sure a TBS wouldn't hurt,

but can't imagine any of those would cause this sudden, intermitent complete loss of power.

Give me some ideas! What do I need to check?

EDIT: forgot to mention, recalls for ignition and altitude issue were performed with less than 13,000 miles on the bike.

 
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Are the 'cut outs' at all related to hitting bumps?

Wondering if your side stand switch is getting tripped momentarily.

This may be unlikely as normal operation of the switch requires the side stand to be fully deployed.

Cheers!

Mike

EDIT:

Could put it on center stand and check to see if moving the side stand out a bit causes it to cut out. (be very careful as you would need it running and in gear)

 
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I'm betting you are in the process of being bitten by a spider. My 07 had intermittent quick power cutoffs and also headlights dying for months until the headlights finally failed hard. In my case, the grounding spider above the left headlight was the problem. I also had signs of future spider bite under the tank on the left side (I believe it's been named S4?).

If you do find that this is the case, please go to www.safercar.gov and report your failure. Make sure to stress that this is a highly dangerous failure that could lead to loss of life ( for example: power cutting just as you pull out into the street with oncoming traffic). We need lots of reports to force Yamaha to fix this dangerous problem!

 
Have you checked the plugs? I am no mechanic but same thing was happening with my car rep[laced plugs and wires and all good

 
Given everything I have read on the subject, I think I would be surprised if it *wasn't* a spider bite.

 
Thanks guys. So the spider/ground issue does NOT result in a loss of electrical power? That's why I was thinking fuel related because my GPS stays fully powered, and I'm not seeing anything on the dash to indicate a disruption of electrics. ( because of that, I've not researched the spider symptoms either, so I'm just asking for clarification).

For the sidestand question, no, it's not related to bumps in the road, nor to engine load, acceleration or deceleration.

I did do the dielectric grease in ALL the spiders way back at 15,000 miles or so. I checked them probably 6-8 months ago and they all looked perfect, but I DID regrease and add a ground wire to the battery from the headlight area per the Randy spider harness type fix. That was just because I was in there and figured it couldn't hurt. All that being said, my right headlight did go out a week or so ago, both beams out. Both high and low beam on that light were working within the last month, so that's a little strange.

Guess I'll be pulling everything apart this weekend, doing plugs, oil, checking all those spiders and connections. Not all bad, I have an AmpliRider that I've been wanting to install under the seat.

Post up any more thoughts you have though.

 
Depending on which spider goes out, you will have different symptoms. For instance S4 (I think) is most commonly associated with engine symptoms like yours. I imagine one of the spiders has grounds coming from the instrument cluster and would cause that to go all wonky without bothering the engine..... (I think I saw someone posting about one of those a week or so ago)

 
You might not lose power to everything. My bet is that you are so busy while the engine is cutting out that you don't have time to do a detail inventory. The spider bite causes you to lose ground. Some circuits remain grounded and completed while others go incomplete. When S4 goes completely, it takes out a lot of things.

When you raise the tank, reconnect the fuel pump plugs, turn on the ignition and wiggle the S4 connector around. If that is the problem, you'll see some interesting instrument displays.

Good luck.

Dan

 
Thanks guys. So the spider/ground issue does NOT result in a loss of electrical power? That's why I was thinking fuel related because my GPS stays fully powered, and I'm not seeing anything on the dash to indicate a disruption of electrics. ( because of that, I've not researched the spider symptoms either, so I'm just asking for clarification).

For the sidestand question, no, it's not related to bumps in the road, nor to engine load, acceleration or deceleration.

I did do the dielectric grease in ALL the spiders way back at 15,000 miles or so. I checked them probably 6-8 months ago and they all looked perfect, but I DID regrease and add a ground wire to the battery from the headlight area per the Randy spider harness type fix. That was just because I was in there and figured it couldn't hurt. All that being said, my right headlight did go out a week or so ago, both beams out. Both high and low beam on that light were working within the last month, so that's a little strange.

Guess I'll be pulling everything apart this weekend, doing plugs, oil, checking all those spiders and connections. Not all bad, I have an AmpliRider that I've been wanting to install under the seat.

Post up any more thoughts you have though.
+1 on this being related to one or more of the Spiders.

I would suggest ordering the Brodie grounding harness to install while you've got everything apart, since from what "we" have learned about the spiders to date a failure is simply a matter of when, not if, so installing the full grounding harness that Brodie sells will once and for all remove this issue out of the equation. Also, remember the spider problem is the result of a poor design, so the system is marginal to begin with, so what I'm getting at is that just because you can't see any obvious burnt wires/connectors right now does not necessarily imply that you're safe...

 
This evening I had two short hesitations within a couple miles of work, then 45 miles with no issues at all.

I ran through all the diagnostics on the computer, an easy place to start before I start tearing into things, which I won't really be able to do fully until the weekend. Battery connections are all tight and clean.

The TPS checked out going from 16 to 100, no dropouts or skipped numbers anywhere. I'm amazed how sensitive that thing is to movement.

On the other diagnostics, everything check well except for... Diag-03, for air intake pressure, I should have been able to press the start button, and if the number changes, the sensor is good. In my case the number, 99, did NOT change. I tried a few times. Started and ran the bike, tried again, I could not get it to tell me the intake air pressure sensor was good. I don't really know what effect this has if that sensor is in fact not working.

For tripped codes, I had a 30 and 41. 30 is Lean angle cut-off switch activated. I have dropped the bike one time since I've owned it about a year ago. The other code. 41 is Lean angle cut-off switch disconnected or short-circuited. I'm not sure what to think about that. I reset those codes, started the bike and let it idle a while. Checked again and neither came back. (I've not checked or reset these codes ever, they could have been there since day one).

I've never any type of engine warning light, or codes showing on the dash, except these I just saw where I actually went into the diagnostic mode to search for them.

So at this point, I'll be taking the recommended step start getting at the spiders and checking them all out. I may go pull the tank this evening and have a look at S4.

Point taken on doing the wiring harness fix and all that, but first I want to actually identify what this problem is.

Thanks for the help guys.

 
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I've pulled the tank and the 4 spider connectors I can get to there all look good as far as I can tell, still have dielectric grease, i don't see any signs of corrosion or heat damage.

I hooked the tank up and cranked it. No amount of messing with any of those 4 connectors caused any cut outs. I was squeezing and separating the wires where they enter plug. Turned on high beams, driving lights, voltage stayed above 13.

I know there are a couple more of those connectors in the dash area, and maybe another toward the back, left side?

So far, no hints other than the codes mentioned in the above post.

 
Wiggle your Ignition Switch Wires at the Base and see if this does anything...
It made my headlight come back on :) Both high and low beam on the left are back. (well, not from ignition switch wires, I reach up under the dash area and was moving everything around in there.)

Didn't make the engine stop though.

 
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Over the weekend, I pulled all the Tupperware, replaced plugs with new NGK iridiums, changed oil, and checked all the spiders. ( and every other connection I could find)

I did not see a single sign of a problem, BUT I went ahead and removed all 8 of them. Cut each one off, stripped, twisted, soldered, black siliconed and taped them all up. I also ran the grounds from the headlights to my battery, ( I already have all my accessories going direct to battery). So at this point, each spiders ground wires are directly connected to each other, and by diverting the headlight ground I've reduced the current going through some of them below stock.

While doing all that, I also hardwired my radar detector and installed an AmpliRider amp. (which I loved this morning)

Yesterday a 10 mile test drive, and 50 miles this morning and I didn't have a single cutout of the engine. The last 3 of those trips I had at least two times where the engine cutout. Not 100% sure it's fixed, I mean, how do you know when an intermittent problem goes away, but it seems ok so far.

Thanks for all the suggestions.

 
Floridave,

Congrats on your fix and creative ways to solve the problem. These connections, from what I've read, even though they may look good, can still be a problem... but they should not cause you future problems.

Good Job and Thanks for sharing your fix!

 
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