Accelerator Position Sensor (APS) Adjustment

[maximo]

On 4/25/2020 at 7:32 PM, texscottyd said:

... early bikes, which are known for having somewhat abrupt on/off throttle response.  

The master of the understatement. My '15 tried its darnedest to kill me with the lurching, over and over again. 

[wordsmith]

3 hours ago, maximo said:

The master of the understatement. My '15 tried its darnedest to kill me with the lurching, over and over again. 

I recall that one professional road-tester/ writer for a UK biking magazine experienced the same thing while out on a test-ride, and unequivocally advised that the bike was so dangerous in this condition that it should not have been allowed out on the road.

[texscottyd]

55 minutes ago, wordsmith said:

I recall that one professional road-tester/ writer for a UK biking magazine experienced the same thing while out on a test-ride, and unequivocally advised that the bike was so dangerous in this condition that it should not have been allowed out on the road.

That seems a bit extreme, but I get the general point of the comment.   I rarely used A-mode with the stock fueling, since the throttle transitions could be very abrupt.   Since the 2WDW reflash, it’s A-mode all the time, and the throttle is smooth and predictable.    

[com3]

Extreme assessments indeed. 

[kltk1]

Hey folks, just wanted to throw my experience in here. I purchased a 2015 FJ-09 with 1600 miles on it last year and could never get comfortable with the throttle. I read everything here and got sidetracked with a home purchase. Having forgotten about the APS modification I sent the ECU out to Vcyclenut for a flash last month and I was quite disappointed when the flash didn't improve the bike much over stock as far as throttle response and found riding in B mode to be much more in tune with how I like to ride and actually enjoyed the bike. I finally remembered this thread and followed the instructions. In the end I dialed back diag 14 to position 13, and diag 15 to 12. For me this change is what I was hoping to achieve with the flash. I'm not at all sorry for having the flash done, however, the APS change has transformed the bike from B mode being the only enjoyable throttle to STD mode now being what I hoped it always would be. It's still a little aggressive going from off-throttle to on-throttle at high RPM (7k+) and I may dial it back to 12, possibly 11, to see if that clears it up. 

All that said, my advice to anyone reading through this thread looking to smooth out the throttle, doing this mod is where you might wanna start before spending any money.

Edited June 6, 2020 by kltk1

[tktplz]

7 hours ago, kltk1 said:

All that said, my advice to anyone reading through this thread looking to smooth out the throttle, doing this mod is where you might wanna start before spending any money.

I've had my 2015 for 3 years now and after the re-flash I too was still riding mostly in "B" mode in the twisties to keep the herkey-jerky from occurring. I'm used to using engine braking, on and off the throttle during high RPM riding through the curves. I will plan on this as a mid-summer update when it's too hot to ride around here, mid-July through the 1st of September. Maybe then I will be happy in "A" mode. Thanks for the update/review.

[betoney]

7 hours ago, kltk1 said:

Hey folks, just wanted to throw my experience in here. I purchased a 2015 FJ-09 with 1600 miles on it last year and could never get comfortable with the throttle. I read everything here and got sidetracked with a home purchase. Having forgotten about the APS modification I sent the ECU out to Vcyclenut for a flash last month and I was quite disappointed when the flash didn't improve the bike much over stock as far as throttle response and found riding in B mode to be much more in tune with how I like to ride and actually enjoyed the bike. I finally remembered this thread and followed the instructions. In the end I dialed back diag 14 to position 13, and diag 15 to 12. For me this change is what I was hoping to achieve with the flash. I'm not at all sorry for having the flash done, however, the APS change has transformed the bike from B mode being the only enjoyable throttle to STD mode now being what I hoped it always would be. It's still a little aggressive going from off-throttle to on-throttle at high RPM (7k+) and I may dial it back to 12, possibly 11, to see if that clears it up. 

All that said, my advice to anyone reading through this thread looking to smooth out the throttle, doing this mod is where you might wanna start before spending any money.

Glad to hear that the adjustment helped you, I set mine to 12 and really like the difference.  On the FZ09 forum, one of the popular options to smooth out the throttle transition is a G2 Throttle Tamer.  It has a cam shaped profile which alters the initial cable pull so it isn't a 1:1 ratio.

G2 Street Tamer Throttle Tube - Yamaha

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The G2 Street Tamer Throttle Tube for Yamaha improves control of...

 

[kltk1]

1 hour ago, betoney said:

Glad to hear that the adjustment helped you, I set mine to 12 and really like the difference.  On the FZ09 forum, one of the popular options to smooth out the throttle transition is a G2 Throttle Tamer.  It has a cam shaped profile which alters the initial cable pull so it isn't a 1:1 ratio.

G2 Street Tamer Throttle Tube - Yamaha

---

The G2 Street Tamer Throttle Tube for Yamaha improves control of...

 

That’s an interesting option. Certainly less expensive than a flash. Will try another adjustment then see what happens. Bike is just about what I want as it is now and I’m hoping dropping to 12 or 11 will clean it up further.  Thank you. 

[texscottyd]

3 hours ago, betoney said:

On the FZ09 forum, one of the popular options to smooth out the throttle transition is a G2 Throttle Tamer.  It has a cam shaped profile which alters the initial cable pull so it isn't a 1:1 ratio

Just my opinion, but I’ve never been a fan of this idea.   Full disclosure:  My real world experience with this is limited to only about 50 miles on an FZ9, but here was my impression:  Yes, it does mute the initial throttle response, but it also gives a very unnatural feeing when the transition back to the standard throttle turn ratio occurs.  On several occasions I found this when leaned over mid-turn, and rolling the throttle back on to accelerate out...  exactly when you do want a linear and predictable throttle response.  Instead, it seemed to come on faster than I expected, since each incremental degree of throttle opening seemed to give proportionately more actual acceleration. 

It’s a conceptually clever band-aid, but a flash & APS adjustment is the right way to go. 

[betoney]

1 hour ago, texscottyd said:

Just my opinion, but I’ve never been a fan of this idea.   Full disclosure:  My real world experience with this is limited to only about 50 miles on an FZ9, but here was my impression:  Yes, it does mute the initial throttle response, but it also gives a very unnatural feeing when the transition back to the standard throttle turn ratio occurs.  On several occasions I found this when leaned over mid-turn, and rolling the throttle back on to accelerate out...  exactly when you do want a linear and predictable throttle response.  Instead, it seemed to come on faster than I expected, since each incremental degree of throttle opening seemed to give proportionately more actual acceleration. 

It’s a conceptually clever band-aid, but a flash & APS adjustment is the right way to go. 

 I don't have any experience with them as I have never used one, only followed the product from the dirt bike world.  I'm not sure if it is the G2 model specifically but one of them came with multiple, interchangeable cam's with different profiles for different terrain.  The rougher the track, the shallower the cam profile and the opposite for a smoother track.

[com3]

On 6/6/2020 at 2:55 PM, texscottyd said:

Just my opinion, but I’ve never been a fan of this idea.   Full disclosure:  My real world experience with this is limited to only about 50 miles on an FZ9, but here was my impression:  Yes, it does mute the initial throttle response, but it also gives a very unnatural feeing when the transition back to the standard throttle turn ratio occurs.  On several occasions I found this when leaned over mid-turn, and rolling the throttle back on to accelerate out...  exactly when you do want a linear and predictable throttle response.  Instead, it seemed to come on faster than I expected, since each incremental degree of throttle opening seemed to give proportionately more actual acceleration. 

It’s a conceptually clever band-aid, but a flash & APS adjustment is the right way to go. 

heh....you should try a quick turn throttle....like 1/4 turn or even 1/8th turn throttle.  i ride lots and lots of superbikes/race bikes.... 1/8th turn throttle is pretty gnarly. haha.

 

Edited June 10, 2020 by com3

[texscottyd]

2 hours ago, com3 said:

heh....you should try a quick turn throttle....like 1/4 turn or even 1/8th turn throttle.  i ride lots and lots of superbikes/race bikes.... 1/8th turn throttle is pretty gnarly. haha.

 

I hear you on that... I’ve typically run 1/4 turns on all my race bikes, and have logged literally 1,000s of race miles over 15 years of endurance and sprint racing.   I tried an 1/8th turn one time, on my built Hawk with FCR flat slides (from the bygone days of carburetors)... suffice it to say that was not a good combination.   

My semi-issue about this throttle tamer isn’t the ratio, but the way the ratio changes...  just felt really unnatural to me on my brief exposure.   

[com3]

1 hour ago, texscottyd said:

I hear you on that... I’ve typically run 1/4 turns on all my race bikes, and have logged literally 1,000s of race miles over 15 years of endurance and sprint racing.   I tried an 1/8th turn one time, on my built Hawk with FCR flat slides (from the bygone days of carburetors)... suffice it to say that was not a good combination.   

My semi-issue about this throttle tamer isn’t the ratio, but the way the ratio changes...  just felt really unnatural to me on my brief exposure.   

Fair enough!  My buddy's sv super bike build with flat slides, etc (85hp on the dyno!) with 1/8 turn was....fun. Haha.  I loved the hawk in track trim too. My buddy Bobby (rip) had one that he raced and would back it in to every corner. 

[iitywygms]

Seems like the 2017-2020 models may not benefit from this?

 

[betoney]

9 hours ago, iitywygms said:

Seems like the 2017-2020 models may not benefit from this?

 

It "might" be possible but not in the same way that you could on the '15-'16.  On the early models you could go into a diagnostic screen on the dash and watch the values change, with the new models you more than likely need a scan tool.