Uncle Hud
Just another blob of protoplasm using up your oxyg
Glad you have your redhead back in the garage. More glad to hear she may be running properly.
2014 Stumble on accel.
- Thread starter Bill Lumberg
- Start date
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BikerGeek99
Yeah, it's a concrete corn cob. So?
Glad to hear you're back in the saddle!
Going to post this here, because we really don't need a bunch of different threads about the same problem. Maybe the OP (or an admin) will be good enough to edit the title of the thread to "3rd Gens - Stumble on Accel" so that it is more correct. Why change the title? Because this apparently is not only on 2014's.
In our trip down to EOM last week, we hooked up in Virginia with BigOgre (MIke from the Isle of Long) for a couple of days of Skyline Drive and Parkway touring. When we got down to the Ashville, NC area we jumped off the parkway and rode up some squiggly lines on the map that called for some higher rpm. Plus it was getting warmer in the afternoon, as it is wont to do in the southlands.
When we stopped for a break, Mike said that he was experiencing the same problem that he had felt when he was riding hard out west earlier in the summer out at the Red Lodge Rendezvous: As he tried to roll-on throttle the bike was hesitating to accelerate until suddenly it would "catch" and nearly shoot out of the turns. A light bulb went on over my head as he described this, and I told him that we'd be on some easy cruising roads for a while, lets see what happens to the symptoms as the bike cools down. Sure enough, the symptoms went away and are only appearing for him when the engine is highly heat soaked, like at the end of a good hard romp, or high speed highway running in hot weather.
I know this heat relationship is a classic TPS failure symptom both from my own first hand experiences and others' past reports. When the contact is first degrading it seems to come on when highly heated and then go back to normal operation when cooled off. Whether the symptoms occur at the first crack of the throttle or with the throttle in a more open position is going to depend on whether you do a lot of riding around town or out on the highway, as that will affect where on the TPS'es carbon track gets the most severe wear.
Discussing the possibilities on a 3rd Gen we've decided that, since the new bikes have Fly By Wire, either the APS (Accelerator Position Sensor) or the TPS (Throttle Position Sensor), which are very similar devices, could cause these kinds of symptoms. The trick will be to come up with a way to easily determine which of the two hundred dollar sensors is the culprit when it happens.
I suggested that when the bike is in the failure mode we may be able to use the cruise control to try and reproduce the symptom, and thereby eliminate the APS as a possibility (if you can reproduce it while on CC) since the ECU mostly ignores the APS during cruise control use. Unfortunately it will probably be hard to reproduce in situations like Mike's since it is happening at the first crack of the throttle, and cruise control has a minimum speed to engagement, but it still may be possible if you ride with the cruise on over hills steep enough that the CC closes the throttle fully. Just an idea...
I suggested that Mike bring the Bike to his dealership and explain the symptoms in detail as above, and also relay that he had the TPS problem on his 2004 many years ago and it was exactly the same. Maybe the dealership will be willing to try replacing the TPS rather than the entire throttle body per the FSM.
The main point of this (too long as usual) post is that Mike's bike is a 2015. So we now have reports of both '14's and '15's with apparent TPS issues.
Have any 2013s seen this issue yet? Maybe the TPS supplier was different, or the batch was unaffected, back in 2013?
In our trip down to EOM last week, we hooked up in Virginia with BigOgre (MIke from the Isle of Long) for a couple of days of Skyline Drive and Parkway touring. When we got down to the Ashville, NC area we jumped off the parkway and rode up some squiggly lines on the map that called for some higher rpm. Plus it was getting warmer in the afternoon, as it is wont to do in the southlands.
When we stopped for a break, Mike said that he was experiencing the same problem that he had felt when he was riding hard out west earlier in the summer out at the Red Lodge Rendezvous: As he tried to roll-on throttle the bike was hesitating to accelerate until suddenly it would "catch" and nearly shoot out of the turns. A light bulb went on over my head as he described this, and I told him that we'd be on some easy cruising roads for a while, lets see what happens to the symptoms as the bike cools down. Sure enough, the symptoms went away and are only appearing for him when the engine is highly heat soaked, like at the end of a good hard romp, or high speed highway running in hot weather.
I know this heat relationship is a classic TPS failure symptom both from my own first hand experiences and others' past reports. When the contact is first degrading it seems to come on when highly heated and then go back to normal operation when cooled off. Whether the symptoms occur at the first crack of the throttle or with the throttle in a more open position is going to depend on whether you do a lot of riding around town or out on the highway, as that will affect where on the TPS'es carbon track gets the most severe wear.
Discussing the possibilities on a 3rd Gen we've decided that, since the new bikes have Fly By Wire, either the APS (Accelerator Position Sensor) or the TPS (Throttle Position Sensor), which are very similar devices, could cause these kinds of symptoms. The trick will be to come up with a way to easily determine which of the two hundred dollar sensors is the culprit when it happens.
I suggested that when the bike is in the failure mode we may be able to use the cruise control to try and reproduce the symptom, and thereby eliminate the APS as a possibility (if you can reproduce it while on CC) since the ECU mostly ignores the APS during cruise control use. Unfortunately it will probably be hard to reproduce in situations like Mike's since it is happening at the first crack of the throttle, and cruise control has a minimum speed to engagement, but it still may be possible if you ride with the cruise on over hills steep enough that the CC closes the throttle fully. Just an idea...
I suggested that Mike bring the Bike to his dealership and explain the symptoms in detail as above, and also relay that he had the TPS problem on his 2004 many years ago and it was exactly the same. Maybe the dealership will be willing to try replacing the TPS rather than the entire throttle body per the FSM.
The main point of this (too long as usual) post is that Mike's bike is a 2015. So we now have reports of both '14's and '15's with apparent TPS issues.
Have any 2013s seen this issue yet? Maybe the TPS supplier was different, or the batch was unaffected, back in 2013?
Iris
formerly "herfjr"
I believe SteveC677 may have been experiencing these symptoms. He has a 2013.
At EOM he thought it had been fixed, but then said after more riding, it was stumbling again.
At EOM he thought it had been fixed, but then said after more riding, it was stumbling again.
stevec677
Well-known member
Yup. Going back in the shop on Tuesday.
BigOgre
Well-known member
Let us know how it goes please? I'm not looking forward to dealing with this, especially as I don't have a dealership I feel good about.
Bill Lumberg
Merica
The throttle body assembly replacement sure fixed mine. Only downside is my bars are way more buzzy than before. Now I understand what people talk about. Before, I had almost no buzz. Go figure. Good luck, Steve.
Maybe you need to do a TB sync? I bet the dealer didn't bother when he slapped them on.
Bill Lumberg
Merica
Would that have an effect on vibes at speed?
No. We can't adjust the linkage anymore, so we are stuck with whatever the mechanical intake balance is of the plates as installed.
jammess
Well-known member
The more I read about the gen3 FJR the more I appreciate my new gen2. As in can't easily look at diagnostics, can't tweak the CO settings, can't adjust throttle linkage, can't adjust idle speed...and then there is the redesigned tupperware which imo is not as easy to install/remove at all.
I can't honestly see why anyone anywhere really needs 6 gears. The cruise control is nice but after doing the throttle return spring unwind it is way easy to just rest your hand on the throttle and maintain your speed. Also, the FJR is happy cruising along at just about any RPM in 5th gear.
I guess if you're the manufacturer you need to continuously come up with some new whistle or bell to sell new models. Never mind the new whistle/bell is not in reality anything to die for let alone shell out bucks for. I have a 2011 Mustang GT with the historic solid axle rear end and Ford comes up with independent just gotta have it rear suspension. Yeah right!
Maybe Bill can get lucky and get his original TB assembly back if Yamaha doesn't want it and re-install and swap the TPS and get his smooth running machine back. The TPS is just a variable resistor so it should be easy to swap the TPS.
Sorry in advance for drifting a bit off topic.
I can't honestly see why anyone anywhere really needs 6 gears. The cruise control is nice but after doing the throttle return spring unwind it is way easy to just rest your hand on the throttle and maintain your speed. Also, the FJR is happy cruising along at just about any RPM in 5th gear.
I guess if you're the manufacturer you need to continuously come up with some new whistle or bell to sell new models. Never mind the new whistle/bell is not in reality anything to die for let alone shell out bucks for. I have a 2011 Mustang GT with the historic solid axle rear end and Ford comes up with independent just gotta have it rear suspension. Yeah right!
Maybe Bill can get lucky and get his original TB assembly back if Yamaha doesn't want it and re-install and swap the TPS and get his smooth running machine back. The TPS is just a variable resistor so it should be easy to swap the TPS.
Sorry in advance for drifting a bit off topic.
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Google (pointing to threads on that other FJR site) seems to think that the TB's can be sync'd on a Gen III, but if Fred says no, I'd be inclined to believe him.
Unbalanced TB's will definitely result in a vibey bike.
Unbalanced TB's will definitely result in a vibey bike.
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ionbeam
2 FUN
Sometimes Fred W takes words coldly exact.
The throttlebodies on the Gen III have adjustable bleeds which you can use to sync the TBs at idle. The TBs do not have adjustable throttle plates which Fred uses to sync the TBs with the throttle partly open. The Owners Manual calls for: Fuel Injection - Synchronization every 4,000 miles.
Since Bill is noting vibrations while at speed, Fred is correct, Bill can't adjust the sync with the throttle plates partly open on the Gen III.
The throttlebodies on the Gen III have adjustable bleeds which you can use to sync the TBs at idle. The TBs do not have adjustable throttle plates which Fred uses to sync the TBs with the throttle partly open. The Owners Manual calls for: Fuel Injection - Synchronization every 4,000 miles.
Since Bill is noting vibrations while at speed, Fred is correct, Bill can't adjust the sync with the throttle plates partly open on the Gen III.
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I never said you can't adjust the Throttle Body Sync. (which really only affects idle and just above)
I said: "No. We can't adjust the linkage anymore, so we are stuck with whatever the mechanical intake balance is of the plates as installed."
I said: "No. We can't adjust the linkage anymore, so we are stuck with whatever the mechanical intake balance is of the plates as installed."
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Heen
Barefooter
I need some help. What is mean by "Fuel Injection - Syncronization" I have assumed that is throtle body sync. I cannot find anything other than that in the FSM. Am I missing something?
ionbeam
2 FUN
ionbeam
2 FUN
Try 2. The first try at answering from a train in North Woodstock NH this afternoon didn't go so well.
As I noted in my post, the term Fuel Injection - Synchronization is from the Owners Manual, the FSM may use a different term entirely. It's common for Yamaha Owners Manuals to speak a different language than the FSM.
BikerGeek99
Yeah, it's a concrete corn cob. So?
I've been following this thread with heightened interest.
While out at NAFO, I noticed that my bike was doing a couple of odd things. First, REALLY low idle. Second, a stumble while accelerating from a standstill.
For the low idle, my bike had always had a low (~750 RPM) idle. I mentioned this at Tech Day and FYB figgered out the problem - the tab where the idle adjuster hits the flux capacitor was missing. He rigged up a fix and - viola! - now my idle adjustment works and it idles at the coveted 1100 RPM.
In an attempt to address the stumble, at Tech Day we changed plugs and did a TBS.
During the EOM trip, the stumble got progressively worse. At the end of the trip, in order to move from a standstill, I had to keep the revs around 4000 and slip the **** outta the clutch. Anyone who was in the EOM parking lot when we left Sunday morning heard it - you should've seen the look on Bungie's face.
I had several discussions with Bust and RaYzerman at EOM aboot the symptoms. Ray is gonna be passing through in a few weeks and we're (OK - he's gonna do it and I'll watch) gonna change the TPS. Hopefully that's the culprit.
BTW - yeah, I know my bike had a recall for the TPS. Several years ago I talked to a local dealer aboot it. They had to order the part. "We'll call you when it comes in." Six months later, I get a call: "Uh, your part has been here for about six months. We forgot to call you." Think I want those idjuts working on my bike? Nosiree.
Anyhoo, if it would be of any value, once we swap out the TPS on my bike, I offer it up to ionbeam or whoever to tear it apart and diagnose it.
While out at NAFO, I noticed that my bike was doing a couple of odd things. First, REALLY low idle. Second, a stumble while accelerating from a standstill.
For the low idle, my bike had always had a low (~750 RPM) idle. I mentioned this at Tech Day and FYB figgered out the problem - the tab where the idle adjuster hits the flux capacitor was missing. He rigged up a fix and - viola! - now my idle adjustment works and it idles at the coveted 1100 RPM.
In an attempt to address the stumble, at Tech Day we changed plugs and did a TBS.
During the EOM trip, the stumble got progressively worse. At the end of the trip, in order to move from a standstill, I had to keep the revs around 4000 and slip the **** outta the clutch. Anyone who was in the EOM parking lot when we left Sunday morning heard it - you should've seen the look on Bungie's face.
I had several discussions with Bust and RaYzerman at EOM aboot the symptoms. Ray is gonna be passing through in a few weeks and we're (OK - he's gonna do it and I'll watch) gonna change the TPS. Hopefully that's the culprit.
BTW - yeah, I know my bike had a recall for the TPS. Several years ago I talked to a local dealer aboot it. They had to order the part. "We'll call you when it comes in." Six months later, I get a call: "Uh, your part has been here for about six months. We forgot to call you." Think I want those idjuts working on my bike? Nosiree.
Anyhoo, if it would be of any value, once we swap out the TPS on my bike, I offer it up to ionbeam or whoever to tear it apart and diagnose it.
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Donal
Well-known member
Even though you can't adjust the throttle bodies it would be really interesting to hook up a Carbtune (or whatever) and note the results at several RPM.
At least you would know if you had a problem there..............
