06 throttle response

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tripletango

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I have had some pretty hairy take offs on my AE. The throttle response from trailing to on is very difficult to modulate smoothly. It's completely different to the throttle action of my 05 and I don't like it at all in comparison.

First the throttle mechanism is extremely stiff. I have to use a cramp buster to stop my wrist from going numb after 10 minutes.

Secondly, the response is immediate from off to on. There is no in between - it is like a switch and almost impossible to do smoothly unless the throttle is moved through 1% of its movement over a period of a second.

This results in jerky acceleration while the bike is in any gear. Seems to slam the rear end spline as well. Not too good for that part as well as the rest of the gear train.

Anyone got an idea?

Throttle position sensor?

Throttle spring?

Any comments or suggestions?

 
I have had some pretty hairy take offs on my AE. The throttle response from trailing to on is very difficult to modulate smoothly. It's completely different to the throttle action of my 05 and I don't like it at all in comparison.First the throttle mechanism is extremely stiff. I have to use a cramp buster to stop my wrist from going numb after 10 minutes.

Secondly, the response is immediate from off to on. There is no in between - it is like a switch and almost impossible to do smoothly unless the throttle is moved through 1% of its movement over a period of a second.

This results in jerky acceleration while the bike is in any gear. Seems to slam the rear end spline as well. Not too good for that part as well as the rest of the gear train.

Anyone got an idea?

Throttle position sensor?

Throttle spring?

Any comments or suggestions?
There's been a ton of discussion on these issues on the base '06. Likely the fixes (center spring release, Fred shim, CO adjustments) would help the AE as well. Search on "Fred shim" and you'll find a boat load of good info.

 
Unhooking the center throttle spring.

Jumper mod.

Lessening/removing the slack on the throttle cable.

And balancig the T-bodies

All the above combined make a big difference.

For me, balancing the T-bodies was the last thing I did and made the biggest difference in itself. They were in spec before I balanced...but I fiddled around with them anyway,... got them a bit closer and it made a big diference.

 
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The throttle pulley on the 06 models has been changed to have a progressive pull. This means the throttle action is non-linear, and small changes at lower throttle positions now result in larger changes at the throttle plates.

The best way I have found to address this is to modify the throttle pulley so that is no longer has a proggressive pitch. I did this by adding a copper wire shim to the center of the pulley. Another member did it with a piece of a rubber O ring inserted in the pulley, which may actually be a better way to do it. What the modification does, is effectivly increase the diameter of the pulley which reduces the throttle plate action some and gets rid of the non-linear throttle pulley action.

You can see photos of my modification here:

https://www.pbase.com/fredharmon/thottlepulley

I don't know how this mod will impact the AE automatic clutch engagement though. It may not be an issue, but at this point is an unknown. You might just have to try it and see if it has any negative impact on it for yourself. My suspicion is that it won't.

 
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hmmm interesting stuff.

I also notice this "jerky-ness" of the throttle. I'm going to see if I can adapt to it before I start modifying my new AE.

I notice it at starts and also when lifting off - especially on the freeway. That's what bothers me the most: lifting off on the freeway and having the bike almost "brake" with how much it lets off the RPMs. It's not a good thing for a passenger. I'm "prepared" because I know when I'm going to let off the throttle but not my passenger...

 
I have had some pretty hairy take offs on my AE. The throttle response from trailing to on is very difficult to modulate smoothly. It's completely different to the throttle action of my 05 and I don't like it at all in comparison.First the throttle mechanism is extremely stiff. I have to use a cramp buster to stop my wrist from going numb after 10 minutes.

Secondly, the response is immediate from off to on. There is no in between - it is like a switch and almost impossible to do smoothly unless the throttle is moved through 1% of its movement over a period of a second.

This results in jerky acceleration while the bike is in any gear. Seems to slam the rear end spline as well. Not too good for that part as well as the rest of the gear train.

Anyone got an idea?

Throttle position sensor?

Throttle spring?

Any comments or suggestions?
I have 1500 miles on my AE and have observed what you're talking about. I removed the center spring and took out as much of the free play in the throttle as I could and this helped, but taking off from a dead stop still takes much concentration. One of my friends I rode to Laguna Seca with this weekend asked me why I seemed to be so timid pulling into traffic or crossing traffic. I have noticed I wait for a much larger clear space so I can pull out without launching erratically and startling myself. My opinion, at the risk of being called a whiner or a non FJR worshipper, is buy the A and forget the AE.

 
Thanks for the input. I had a long chat with the yamaha techies at their MotoGP tent. They are aware of this situation. One of the guys rode an AE from Sca and noticed the heavy throttle and switch like response.

My bike is going in to Bay Area Yamaha on wednesday before the WFO and I will ask for those actions suggested to be carried out.

I am sure they won't remove springs or add shims but at least they will do the throttle bodies.

BTW it helps to start in second as it slips the clutch a little more which smooths take off in traffic.

 
The throttle pulley on the 06 models has been changed to have a progressive pull. This means the throttle action is non-linear, and small changes at lower throttle positions now result in larger changes at the throttle plates.
The best way I have found to address this is to modify the throttle pulley so that is no longer has a proggressive pitch. I did this by adding a copper wire shim to the center of the pulley. Another member did it with a piece of a rubber O ring inserted in the pulley, which may actually be a better way to do it. What the modification does, is effectivly increase the diameter of the pulley which reduces the throttle plate action some and gets rid of the non-linear throttle pulley action.

You can see photos of my modification here:

https://www.pbase.com/fredharmon/thottlepulley

I don't know how this mod will impact the AE automatic clutch engagement though. It may not be an issue, but at this point is an unknown. You might just have to try it and see if it has any negative impact on it for yourself. My suspicion is that it won't.
The clutch is fine on the AE. Modulating the throttle is a problem making take offs interesting if in a situation you have to get going like NOW. This progressive throttle that has appeared on the 06s makes this difficult.

I am sure the heavy throttle return springs are there to make sure the throttle closes all the way. This is important on an AE as the clutch requires revs to drop below 1300 for disengagement. Any throttle opening above total close and you are moving like it or not when trickling along in traffic as the clutch will not disengage. You can overcome this by braking against the small amount of drive that is coming from the engine - it is a little un nerving though. This lack of complete throttle closure is due to a throttle rocker that has been installed to overcome the extremely stiff throttle and is slightly misadjusted for the situation. You soon learn to rotate it out of the way in traffic!

Other problem with the switch like throttle response is that it is hell on the transmission banging the back end something fierce especially when in traffic. On off on off drives you crazy. bang bang - wonder how long the tranny will last!

 
This IS an issue with the FJR. I have done all of the mods mentioned above and they have helped a great deal. But we are still skirting the issue. There is a problem either in the computer mapping or in the sensor/control system for this motor that is creating this on-off ness it has. This problem is really bugging me as it is my only real complaint with this bike. Reportedly the 05's were not like this, or at least not to this degree. I wish Yamaha, seeings as they know how the computer logic works, and they know the changes they made to the 06, would give us a fix. It's pretty hard for the average guy to find the answer when you don't have the computer logic, but this winter I sure will be trying some things to see if I can at least find something that's and improvement. I suspect it will be in the engine computer sensor systems.

(Administrator induced dogpile expected for speaking out against the idol FJR.)

 
I don't know how this mod will impact the AE automatic clutch engagement though. It may not be an issue, but at this point is an unknown. You might just have to try it and see if it has any negative impact on it for yourself. My suspicion is that it won't.

My guess (key word *guess*) is that it would not have any effect on the AE operation. The computer pulls the throttle info from the TPS, which is measuring the butterfly-axle's position, right? This would mean that any change you made to the cable end of the operation would not be noticed by the system, as long as the throttle still returned to the stop fully.

 
This IS an issue with the FJR. I have done all of the mods mentioned above and they have helped a great deal. But we are still skirting the issue. There is a problem either in the computer mapping or in the sensor/control system for this motor that is creating this on-off ness it has. This problem is really bugging me as it is my only real complaint with this bike. Reportedly the 05's were not like this, or at least not to this degree. I wish Yamaha, seeings as they know how the computer logic works, and they know the changes they made to the 06, would give us a fix. It's pretty hard for the average guy to find the answer when you don't have the computer logic, but this winter I sure will be trying some things to see if I can at least find something that's and improvement. I suspect it will be in the engine computer sensor systems.
(Administrator induced dogpile expected for speaking out against the idol FJR.)
+1 :(

 
Where it bothers me the most is when I am stuck in stop and go traffic. Its completely annoying not to be able to modulate the throttle in such a way that you can get smooth starts and stops. I must say that I haven't done Freds shim mod but found that just doing the Barbarian jumper made a world of difference. Unfortunately, I rely on the dealer for things such as a TBS....I made them aware of the problem, they told me they did the synch, but not only did I not notice a change, I don't even think they so much as lifted the tank. I've got it going in for service shortly and will mark the fasteners with nail polish this time to see if they are even doing what they say they are

 
Thinking out loud.

Maybe someone with more fuel injected knowledge than I can answer this theory:

It seems the throttle jerkiness is due to the throttle being opened a tad, then the fuel being induced, so it gives it this snap, rather than a smooth transition.

If the TPS switch is supposed to be set at 8 to 14 at idle, (I don't rmember the exact numbers, just hypothetical here) would there be an improvement if we readjusted to the high side, so the computer would get the fuel in as soon as we advance the throttle, rather than what seems like a moments delay, then a big hit?

I guess what we need to know is, does the TPS give actual throttle position, or does it give rate of change, or both? Has anyone tried this? I just bought some security bits and will try this out this week. Mine is set right in the middle of the idle range right now. Maybe all for nothing but when you are grasping at straws you gotta start somewhere. Part of learning what it is, is learning what it isn't.

And, I am still intrigued by, I think it was Ionbeam's comment, that the bike seemed to run differently (better) when he had the vaccum gage and hose connected, creating a vaccum resevoir. Hmmmm.

 
Thinking out loud II -- >

My FJR has been a surger since new. What I refer to as surging happens during light engine load and small throttle transitions or on hills while the engine is in the 3-4k rpm range and most noticeable in lower gears. I'm sure the reason it isn't so noticeable in the higher gears is just because of higher engine loading. My FJR feels like it applies too much deceleration fuel cut-off then over compensates with too much enrichment which then over revs the throttle setting so it has to severely cut off fuel causing too much rev drop for the throttle setting.......

Some elements that can cause surging are:

  • drive line slop
  • plugged air filter
  • TBS
  • very lean mix or vacuum leak
  • loose cam chain effecting valve operation
  • ECU software not correct for light loads, short gears
  • sensors that feed the ECU information not working correctly
  • mechanical problems with the fuel pump or fuel pressure regulator
  • ignition timing 'floating'
  • play between the throttle body blades and the TPS shaft
As part of my TPS failure troubleshooting I have done so much work that I'm now spending some time looking into my surging.
  • My drive line slop is equal to other bikes that don't surge
  • new air filter
  • TBS spot on
  • no vacuum leak; I've done the CO thingie and have a PCIII
  • I have checked my cam chain tensioner and it's ok. It was a bitch to check.
  • The ECU software is the same for all Gen 1 bikes so if it were the ECU all or none would surge
  • I have now electrically verified all sensors to be working correctly
  • Ah, yes the fuel pressure regulator....
  • I will consider timing after ruling out every thing else only because it will be hard to measure under surging conditions
  • there is no play between the throttle body blades and the TPS shaft
My next round of troubleshooting will have me at the FP regulator but I have to order some parts to let me do a correct troubleshooting process. When I had my vacuum gauge on the FPR it slowed down the FPR response and that did seem to relieve the *symptoms*. A runny nose and cough aren't a cold, they are the symptoms of a cold -- the root cause of the cold is a viral infection. I would like to be sure of the root cause. Does anyone with a known non surging FJR want to swap FPRs with me? ;) Looking at the FPR vacuum signal it was clear that the intake vacuum followed surging and didn't lead like it would if it were the culprit.
Fuel injection is controlled by fuel pressure, ECU injection pulses and the injector solenoid/nozzle. Fuel pressure is controlled by a vacuum signal balancing a spring loaded relief valve in the fuel pressure regulator. I know the vacuum signal is correct but haven't yet determined if the relief valve is operating stabile. The ECU software is the same for all bikes so the injector pulses should be the same. Sensors feed the ECU information about various things such as temperatures, pressures, crank position, cylinder ID and ignition timing. I have 'real time' verified all the sensors except for ignition. It is possible for one or more injector solenoids not to be working correctly. Reading the plugs leads me to believe they are all working the same.

Well, off for a ride. B)

 
If you've done all the mods and are still not happy, your best bet is to add a power commander and have a custom map done.

 
Where it bothers me the most is when I am stuck in stop and go traffic. Its completely annoying not to be able to modulate the throttle in such a way that you can get smooth starts and stops. I must say that I haven't done Freds shim mod but found that just doing the Barbarian jumper made a world of difference. Unfortunately, I rely on the dealer for things such as a TBS....I made them aware of the problem, they told me they did the synch, but not only did I not notice a change, I don't even think they so much as lifted the tank. I've got it going in for service shortly and will mark the fasteners with nail polish this time to see if they are even doing what they say they are
Well, lemmeaxe you a quexion: why haven't you tried the Fred Wire Thing?

That's the only thing I've done to try to fix the problem. It made enough difference that I stopped there.

My VFR had this same issue, though not quite as exciting as the FJR. I solved the problem on the VFR by simply increasing the idle a little bit.

Er, I just remembered, I also took out most of the slack in the th'ottle cable. On the FJR.

 
Had the TBs done and took up the throttle cable. Improves the action a bit but still like a switch from trailing to on. Anyone tried a PC and a Wally smoothness type map with the 06?

No one at the WFO had tried that at least that I talked to.

Freds idea is a good one but I think the base problem is fuel mapping.

Oh Yea i talked to the Yam rep at WFO and he said that Mama was aware of the problem. For whatever that is worth! Shades of ticker head up their ass lip service BS.

 
2K miles now on my '06 with all the mods done save for a PCIII. Fred shim made the most difference. Bike is really smooth now and the throttle is on par with the BMWs I've ridden so I'm calling it good.

FWIW, I rode mine back to back with an '05 and throttle response and action was indistinguishable between the two bikes.

 
Continuing on with my W.A.G. about the throttle position sensor, in that, maybe if it is adjusted to the high side it would change the on/off ness of the throttle.

My bike stalled on me twice recently. The idle speed was 900 RPM and the Throttle Position sensor adjustment was right in the middle of the normal range. So I cranked up the idle to 1200 RPM's and rechecked the TPS setting at idle. It was 16. Almost at the "top" of the normal idle range. Hmmm. So I drive to work and it seems "better." Increasing the idle speed definetely helps quite a bit with drivability. I can't say the On/Off ness of the throttle is gone. However, with all of the mods in place it is at a minimum right now anyway.

Operating under my favorite assumption, "If a litttle does a little good....." I decide to adjust the TPS even higher so I set it to 18 at idle. Just above the recomended range. Going for a test ride now to see what happens.

Will post back in an hour if it is interesting, or 3 hours if it runs like crap and I have to put everything back to normal. LOL

 
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