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Discussion Starter · #1 ·
I have been dealing with a jerky throttle on my 2014 FJR. My bike surges when I'm riding at low speeds even when using my cruse control. I've had my dealer go thru the whole bike 3 times and it still won't go away. I am now thinking about having my ECU flashed. Can any one give my so advice? Also I need some advice/help on how to remove my ECU?
Bob
 

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2013 FJR 1300A
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You can check out Ivan's page... he has instruction on how to remove your ECU/etc. and information about the flash.


Thinking of doing the flash myself to get rid of surging without having to use the clutch.
 

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Discussion Starter · #3 ·
I have checked out Ivan's web sight, but I need more info than he provides. I started digging into my bike but I hit a stone wall. I am having the same problem as you. SURGING
 

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Versys 1000 CBF1000 VFR800
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Do this first..... You might want to check your TPS....... not that easy to diagnose, but go into DiAG and see if it smoothly increases in number at the lowest reading and doesn't jump.... another thing to try is to rotate the TPS so it reads say 19-20 at the lower end... go ride.

I personally don't think the Gen3's really need an Ivan flash all that much. Would hate to see you go for it and find out you still have the problem if the TPS is acting up.
 
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Discussion Starter · #5 ·
I have never heard of the TPS, how do I go about testing it? Is it something I would have to have my dealer do?
 

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Get hold of a factory service manual. Between that and the knowledgeable folks here you save hundreds if not thousands of dealer charges. Nobody here is in business to make money giving advice. And more importantly it will probably be done right.
 

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I don't know your knowledge or skill set.... doesn't sound like your dealer knows much about it, which is not surprising at all. To be fair, they are hard to diagnose.
See the search box above, just type in TPS (Throttle Position Switch) for lots of reading material. It's on the left end of your throttle bodies.

IF you want to take a wee gamble and can't do it yourself, just tell your dealer to replace it without wasting any more diagnosis time.... he should know how to do that and set it up.
If you could, also put your location and bike info in your profile for future reference.
 
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In the Series IIIs, the TPS (Throttle Position Sensor) works in conjunction with the ACS (Accelerator Position Sensor) as part of the ride-by-wire system. When everything is working properly, the TPS, tied to the throttle, sends resistance commands to the ECU. The ECU then sends commands to the servomotor on the throttle body. The motor then changes the position of the butterflies. The ACS is on the same shaft as the butterflies. It reports back to the ECU where the position of the butterflies are. And then the cycle repeats - very quickly (in milliseconds).

When you enable the cruise control, the ECU closes the feedback loop using speed inputs from the ABS wheel sensors to automagically maintain the speed.

Obviously, in a Series III, either the TPS or the ACS can cause surging. I suspect that is why the usual MamaYama approach is to throw parts at the problem, in this case, a new throttle body assembly.

Once you have ABS and ride-by-wire, you have all the hardware you need to implement CC and TC.

Needless to say, the Series I and II do not have an ACS.
 

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I don't know your knowledge or skill set.... doesn't sound like your dealer knows much about it, which is not surprising at all. To be fair, they are hard to diagnose.
See the search box above, just type in TPS (Throttle Position Switch) for lots of reading material. It's on the left end of your throttle bodies.

IF you want to take a wee gamble and can't do it yourself, just tell your dealer to replace it without wasting any more diagnosis time.... he should know how to do that and set it up.
If you could, also put your location and bike info in your profile for future reference.
Bob's symptoms are exactly like the symptoms on my '13 when the TPS started fouling up. It started with a minor blip, usually while trying to roll on smoothly out of slow corners. And it finally got so bad it'd start jerking from time to time going down the interstate on cruise. The dealer couldn't find a problem after me paying for hours of diagnostics. I suggested it might be the Throttle Position Sensor, and he said "We can't just start replacing parts." I said "Well, I can." I ordered a TPS online for $50 less than his price and replaced it myself. Problem solved.

It's not a hard job with some patience. The manual (if I'm not mistaken) says to remove the throttle body to get to it, but I and others here have finagled it out from the left side.

I agree with Ray on the ECU. I had Ivan flash mine to do away with the cruise control limit, and I don't find it improved enough to justify the cost otherwise.
 

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I rode my neighbor's '15 gen3 to the local dealer to have a recall done while he followed in his PU and I agree the gen3 probably won't benefit much from a refresh. Did make a difference on my '10 gen2. As time has passed would I get the flash again? Maybe but then again maybe not but it's done and I can't complain.

I'm kind of loosing interest in motorcycle riding anyway.
 

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Discussion Starter · #11 ·
To all that have responded to my problem with surging/jerky " I Thank You". I am going to start with having my ECU flashed and see how that goes. I removed my ECU today and will be sending it to Ivan's. If my TPS is the problem I will replace that as well. I am the new kid on the block on the FJR owners group, and I Thank you all for the help.
Regards,
Bob
 

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(y)
Be sure to let us know how it goes.
 
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