Flat spot off idle

[Danny G]

Just thought I would put this out there. These forums have saved me hundreds of dollars in repairs. My 2014 fjr developed a flat spot or almost miss off idle. It did not matter what speed. It almost seemed like a miss. Thought it was bad gas, so I drained and refilled. (no help). Replaced spark plugs. (no help). I started searching forums and found one person who had a similar problem. The dealer was going to replace the throttle positioning sensor and the accelerator positioning sensor on his bike. He said it fixed his stumble and rough idle. My bike started and idled fine but something was wrong. I ordered and replaced the throttler positioning sensor only. It runs like a new bike. I was amazed at the difference and started to wonder if this was a more common problem. Hope this post helps someone else like it helped me. Luv the fjr.

 

[RossKean]

This has come up for a few people already. In one instance, the dealer ended out "fixing" it by replacing the entire throttle body assembly!

https://www.fjrforum.com/forum//index.php/topic/167846-2014-stumble-on-accel/page-1

ionbeam's dissection of a TPS:

https://www.fjrforum.com/forum//index.php/topic/169700-anatomy-of-gen-iii-fly-by-wire-tps/?hl=position

 

[mech 1 twa]

Very common on Gen I Yamaha had a recall TPS

I had to replace the recalled one, same issue. miss stumble as throttle is opened.

 

[Fred W]

Yep, it appears that the 3rd Gens are plagued by Throttle Position Sensors that are less than robust, much like the 1st Gens were a decade earlier. Guess they did not learn anything in that go around?

But Yamaha is not alone in this regard, either. There are many other cars and bikes of all brands that also develop TPS problems early in their lives, as there are only a hand full of manufacturers of these type of positional sensor parts, and they all seem to have similar issues.

Technology is out there to use other methods of position sensing (optical encoders, etc.) but that requires departing from the traditional "tried and true". Most design engineers are merely adapters of prior designs to a new application, rather than forgers of new ones. It's why the same problems seem to present themselves in such a widespread fashion.

 

[escapefjrtist]

How many miles were on the bike when the symptoms first developed, and then when you changed the TPS?

--G

 

[Danny G]

The bike had just over 20,000 miles when the symptoms started. The problem was not consistent when it started. Some days it would run perfect and the next it wouldn't. I have added a little over 3,000 miles after the repair. I did purchase the bike new. The other interesting thing was the internal diag showed a slight jump from 17 to about 23 then normal all the way to the top. My friends 13 showed a similar jump, but be has no symptoms. Wanted to also thank the forums on the information to calibrate the sensor once it was installed. It made the whole project seem simple.

 

[escapefjrtist]

Thanks for the info!

--G

 

[Bill Lumberg]

Danny- your symptoms mirrored mine, though it became unrideable after a bit. I had bad luck in the form of initial rudeness and apathy from Yamaha corporate, then months of downtime waiting for a whole throttle body assembly on back order from Japan, with zero adjustment or compensation from Yamaha. I have no doubt that he TPS was the problem on mine. I only got a whole tba replacement because I wanted to have Yamaha repair their defective product under he warranty I paid for. I won on principle and getting the problem fixed cost me zero, directly. But I paid more in gas expense and time spent on the phone with Yamaha than it would have cost to just have the tps replaced on my own dime.

 

[Danny G]

Sorry to hear that .The dealer was useless when I talked to them about my bikes problem. Wanted to do everything else (sync throttle bodies, valve adjustment, spark plugs, injectors) but would not believe the tps could be the problem. When I asked what they would charge just to replace it , I was quoted around $600. Ended up with $129 sensor and about a hours worth of labor.

 

[Bill Lumberg]

I can only hope that Yamaha starts replacing throttle position sensors instead of checking everything else.

 

[BigOgre]

I fear I'm looking at the same issue and don't relish having to argue for a new sensor.

 

[Fred W]

If (when?) it happens to my aesthetically superior 2014, I'll gladly cough up $100 and a couple hours in my garage to swap out the TPS to avoid the aggravation of having to go through the warranty dance others have experienced.

I realize that we are all conscious consumers, have paid a (dear) price for admission for our machines, and feel "entitled" to everything working as new (forever). But, I am a pragmatist above all, and when a bike that otherwise performs as well as (arguably far better than any other machine made for the same purpose) happens to have a little hick-up, and I have the ability to rectify that with a lowly Benjamin and my own time, I'm going to take that easy-path-less-taken 100 times out of a 100.

It's one of the big reasons that I dislike extended warranties at any price on most any purchase. I usually prefer to deal with my unmade bed myself. However, the intricacies and unknowns of the 3rd Gen ES suspension, while attractive beyond all resistance at purchase, pushed me into a YES situation again, even though I made no claims on my 2005's YES. But honestly, I'd still rather fix any problems myself than to become dependent on the Yamaha "support" people.

PS - Mike. We can fix it!

 

[BigOgre]

Yeah, the last thing I want to do is get into a back and forth like Bill L. did. And then even if/when it does get repaired I know I'll be looking for broken fasteners and scratches, etc. and that'll just add to the annoyance. I agree that a couple of hours bonding with it in the garage would probably be more satisfying but still, it irks me to give in.

Guess this would be a good time to throw a set of block-off plates on the shelf for whenever I do get under the hood.

 

[mikerider]

Just thought I would put this out there. These forums have saved me hundreds of dollars in repairs. My 2014 fjr developed a flat spot or almost miss off idle. It did not matter what speed. It almost seemed like a miss. Thought it was bad gas, so I drained and refilled. (no help). Replaced spark plugs. (no help). I started searching forums and found one person who had a similar problem. The dealer was going to replace the throttle positioning sensor and the accelerator positioning sensor on his bike. He said it fixed his stumble and rough idle. My bike started and idled fine but something was wrong. I ordered and replaced the throttler positioning sensor only. It runs like a new bike. I was amazed at the difference and started to wonder if this was a more common problem. Hope this post helps someone else like it helped me. Luv the fjr.

How hard was it to replace the TPS on the 2014? My warranty expires this coming July 2017 (I got 1 year factory warranty + 2 years free YES warranty) and if it goes bad after then, I'll see if I can do it myself.

Thanks.

 

[Danny G]

Easy to replace, but make sure the calibration is right. (found those instructions on forums also).

Danny

 

[its just rain]

I've had similar problems on mine that are described above. The latest fix was to adjust the throttle (after several other fixes were tried) and seemed to smooth it all out. However, I think it still needs a new TPS. I've mentioned more than once that it never has run as smoothly as my '11. If I bought the part would some knowledgeable FJR owner nearby like to practice putting it on, I would pay your going rate. I'm just not enough of a mechanic to try it myself.

 

[Danny G]

Its funny you say that. My 2009 fjr seemed much smoother above 70 mph than my 2014. I know they changed the cylinder from sleeves to coating. I think they may have used a shorter skirted piston too. Don't know if it is my imagination or the 2009 was a smoother bike. That would be an interesting thread.

Danny

 

[its just rain]

Danny, I don't think it's your imagination. Something is definitely different, but then again, there are more likes than dislikes about the new bike.

Garry

 

[roger dodger]

I just received a replacement TPS and wanted to find the 'calibration' sequence for my 2013 A model.

LMK if I can find it in the FSM, or it's just a simple .... Thanks in advance, Roger

Many thanks, Fred!