AE shifting and 1st gear engagement problem solved - incorrect engine oil viscosity

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Great update.

Good news
Yes--good news! I hope this info helps any of those who may be experiencing similar issues with their AE model--those issues being hard 'chattering/clunking' when engaging from neutral to first gear and/or the electronic shifting seems delayed/hesitant especially when downshifting from 2nd to 1st. After much experimenting with various possible 'solutions' --clutch soak, varying engine oils/viscosities, changing the clutch engagement position (both up and down), rebuilding the clutch master cylinder, and, finally, replacing the clutch slave cylinder--I believe I have a pretty clear understanding as to what actually causes the first gear engagement 'chatter'. Here is what I believe to be the problem:

1) As with any standard clutch, the clutch engagement/disengagement is determined by how much pressure is being applied by the clutch pressure plate (assuming the clutch friction plates, etc., are all in within normal specs).

2) The clutch pressure plate's 'position' is determined by the amount of force being exerted onto it (indirectly) by the clutch push rod. The further the push rod is being pushed, the more disengaged will be the clutch...and, conversely, the less pushed the rod, the more engaged will be the clutch.

3) The push rod is ultimately 'pushed'...its position is determined by...how far the slave cylinder piston is advanced which, itself, is determined by how much clutch fluid has been displaced between the clutch master cylinder and the slave cylinder.

4) Now, this begins the point where there is a big difference between the AE model and the 'non-AE' model. In the AE model, the amount of clutch fluid that is displaced toward the clutch slave cylinder is determined, ultimately, by three things (all other things being equal): (a) a rod in the clutch actuator (we'll call it the 'clutch actuator rod' that pushes up against the piston in the clutch master cylinder; (
cool.png
a clutch position sensor that monitors the position of that rod (which, ostensibly, lets the computer deduce how much pressure is (or is not) being applied to the clutch pressure plate. because IT ASSUMES THAT THERE IS NO AIR IN THE CLUTCH LINE); and © the 'condition' of the clutch fluid (i.e., presence of air vs no air in line). If there is NO air in the clutch fluid (and no other anomalies ) then this 'electronically controlled' situation is great. But when there is air in the line, not so much so, because...

5) The AE's computer system 'feathers' the pressure plate based on (a) the current engine speed and (
cool.png
how much pressure it believes that the clutch pressure plate is exerting at that moment. It uses the clutch actuator rod position (again, sensed by the clutch actuator's 'clutch position sensor') to 'tell it' how much pressure is being applied to the pressure plate at any given time. And that works great assuming there is no air in the clutch line. But if there is air in the line, then the distance of the clutch actuator rod (read by the sensor) is no longer an accurate reflection of how much the clutch pressure plate has been displaced at that moment. Specifically, the more air in the clutch line, the less displaced will be the clutch pressure plate (the more 'engaged' the clutch friction plates will be) than what the computer believes to be the case.

6) The AE computer communicates with the clutch actuator, telling it how far (and how quickly) to relieve pressure from the clutch master cylinder's piston...thus relieving master cylinder's displacement of clutch fluid to the slave cylinder piston (that pushes the clutch push rod that ultimately determines how much..or how little pressure... the clutch pressure plate is under). \

7) With air in the line (see 5 above), the computer believes--at any given time--that the clutch pressure plate is more disengaged than it actually is. The result is that the computer will tell the clutch actuator to 'ease off' (bring back) the clutch actuator rod (again, the one that presses up against the master cylinder piston) earlier than it should. AND THAT IS WHAT CAUSES THE ENGINE TO LUG (THE 'CHATTERING' EVERYONE TALKS ABOUT). THE 'CHATTERING IS THE ENGINE LUGGING BECAUSE THE COMPUTER --THROUGH ITS COMMAND TO THE CLUTCH ACTUATOR--IS CAUSING THE PRESSURE PLATE TO RELAX TOO QUICKLY GIVEN THE ENGINE SPEED AT THAT TIME. AND, AGAIN, IT DOES THIS BECAUSE THE AIR IN THE CLUTCH LINE CAUSES THERE TO NO LONGER BE A DIRECT RELATIONSHIP BETWEEN THE CLUTCH PRESSURE PLATE POSITION AND THE POSITION OF THE CLUTCH ACTUATORS ROD.

8) Of course, after correcting for air in the line (i.e., possibly replacing the clutch slave cylinder, clutch lines, and/or rebuilding the master cylinder, etc.), you may need to reset the clutch engagement position (using code SH__66) to obtain proper first gear engagement (I prefer to full engagement occurring around 1800 rpm but that's subjective. Prob anywhere between 1400 and 2000 is okay).

9) BTW, for purposes of doing the clutch fluid flush on the AE, I have been using the 'Ignition switch on/off' method many, many times. It works. You do NOT need to remove the swingarm in order to do a clutch fluid change/flush on the AE. It DOES help to apply a vacuum on the bleed screen (i.e, use a mity-vac or equivalent).

- END-

Again, I hope this sheds some light on (what I believe to be) the cause of the AE 'shuttering/chattering/stuttering'. Or, at least ONE THING that might be the cause.

 
Last edited by a moderator:
Well said. I agree with this. In short, any bubbles in the clutch fluid will cause the computer to become confused. It's extremely important to make sure the system is bled well.

 
OakDave,

Excellent work on that. While my '08 is no more, I still follow AE reports and you've done a thorough job. Hope it all stays 100% from here on out.

 
Well said. I agree with this. In short, any bubbles in the clutch fluid will cause the computer to become confused. It's extremely important to make sure the system is bled well.

OakDave,
Excellent work on that. While my '08 is no more, I still follow AE reports and you've done a thorough job. Hope it all stays 100% from here on out.
Thanks to both of you for following this and your kind words. So far, so good. It's been five days and several hundred miles of riding since replacing the slave cylinder...and the problems (chattering/stuttering when engaging from neutral to 1st...and 2nd->1st gear downshifting delays) have not come back. Before changing the slave cylinder, bleeding the clutch fluid would solve the problem for just a couple of days before those problems would reappear. Obviously, that was because the clutch fluid bleed would clear out the air in the line...for a moment (a couple days)...then the air would slowly suck back in and I was back to square one. That 'clutch bleed fix' was implemented over and over (by me) for several months--until it got to that point where it was needing to be performed every few days. That's when the straw broke the camel's back, so to speak. Again, the fact that it's already been more than a couple of days-- of troublefree engagement and low-gear downshifting-- since having replaced the slave cylinder is, I believe, a pretty strong indication that the problem is 100% solved (at least as long as something else does not cause air to start getting sucked into the clutch line again).

In closing, I do not plan on adding any more to this post UNLESS I discover that this solution turns out to be something other than that. Otherwise--for those of you who have been following along-- just assume that 'no news is good news'. Ciao!

 
UPDATE: It has now been a little over two months...and about 3500 miles ridden...since I reported that replacing the clutch slave cylinder and the associated rebleeding of the clutch line had solved the neutral-to-first hard 'chatter' problem (and the SH__26 error code that would occasionally accompany it). This is to let everyone know that the problems (chatter, and SH__26) have not resurfaced.

 
I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.

 
I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
Only thought: clutch soak? Computer won't change gear if clutch hasn't released, so this might be a symptom of a sticking clutch. Not a hard job, and certainly wouldn't hurt.

 
I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
-You say "I've started stopping in 2nd gear Ang then downshifting to 1st." I don't understand how that is possible without the bike stalling, as the only gear that the AE will allow go into a 'neutral/stopped' state while the engine is running id 1st gear. Rolling to a complete stop in 2nd should cause the engine to stall.-Re the slave cylinder that eventually got replaced: like with yours, it appeared fine upon initial teardown and inspection. But clearly it was not okay. The problem with the seal was obviously something my naked eye couldn't discern.

 
I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
Only thought: clutch soak? Computer won't change gear if clutch hasn't released, so this might be a symptom of a sticking clutch. Not a hard job, and certainly wouldn't hurt.
Clutch soak was performed twice.....No change.

I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
-You say "I've started stopping in 2nd gear Ang then downshifting to 1st." I don't understand how that is possible without the bike stalling, as the only gear that the AE will allow go into a 'neutral/stopped' state while the engine is running id 1st gear. Rolling to a complete stop in 2nd should cause the engine to stall.-Re the slave cylinder that eventually got replaced: like with yours, it appeared fine upon initial teardown and inspection. But clearly it was not okay. The problem with the seal was obviously something my naked eye couldn't discern.
You can stop in 2nd gear and the bike will idle. Never heard any different and I know others who do the same thing. What was it about the slave cylinder that constituted replacing it? Is there something to look for? Thanks.

 
Last edited by a moderator:
I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
Only thought: clutch soak? Computer won't change gear if clutch hasn't released, so this might be a symptom of a sticking clutch. Not a hard job, and certainly wouldn't hurt.
Clutch soak was performed twice.....No change.

I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
-You say "I've started stopping in 2nd gear Ang then downshifting to 1st." I don't understand how that is possible without the bike stalling, as the only gear that the AE will allow go into a 'neutral/stopped' state while the engine is running id 1st gear. Rolling to a complete stop in 2nd should cause the engine to stall.

-Re the slave cylinder that eventually got replaced: like with yours, it appeared fine upon initial teardown and inspection. But clearly it was not okay. The problem with the seal was obviously something my naked eye couldn't discern.
You can stop in 2nd gear and the bike will idle. Never heard any different and I know others who do the same thing. What was it about the slave cylinder that constituted replacing it? Is there something to look for? Thanks.
Ok on the soak. Didn't sound quite right, but I thought I'd ask.

I will re-affirm FJRPittsburg's statement about stopping in second. Assuming your bike has no problems, you can stop in ANY gear, bike will not stall. You can attempt to move off from rest in ANY gear, bike will not stall (but may not move from rest very quickly!).

 
I have the very same problem as described by FJRPittsburgh. I have no problem bleeding via the ignition switch method, however within a day or two the system sucks in air once again. The bike is a 2008 AE, going on 12 years old, and I'm sure the rubber parts in the clutch system have degraded through the years. I'm planning to replace the slave cylinder as well as install the master cylinder kit for the clutch activator.

I believe the whole problem with the delayed downshift has everything to do with air in the system. It's definitely is not a clutch soak issue, I did that as well as drilled a few more holes in the clutch basket to bleed oil into more areas of the clutch plates. That modification had no affect on anything.

I remember these things when it was new, the electronic shift was always spot on! I put mile one on my first '06 and never had an issue. Unfortunately it didn't reach it's fifth birthday when it was taken away from me. My second '06 started having issues when it got to be around 7 years old. I got my '08 when it was around 7 years old, and it never had the same spot on shifting as my first '06. I'm hoping that the replacement parts will restore the system to factory fresh performance.

We shall see.

Brodie

rolleyes.gif


 
Brodie,

I'll be following your quest to fix this issue. Seems like it can't be all that complicated, but the fix has eluded me. Good luck with the trial and error method. Sending '08 AE healing thoughts your way.

Jeff

 
I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
Only thought: clutch soak? Computer won't change gear if clutch hasn't released, so this might be a symptom of a sticking clutch. Not a hard job, and certainly wouldn't hurt.
Clutch soak was performed twice.....No change.

I still have the delayed shifting into first gear on my AE also. It's been that way for over 2 years. Brodie sent me the proper way to bleed the clutch fluid using key cycles. Never fixed my problem. When rolling to a stop in 2nd gear, if I downshift to 1st, the bike doesn't downshift and then grabs in 1st gear as I slow down a bit more. If I downshift to 1st while at 3000 rpm's or higher, it never misses. I've started stopping in 2nd gear and then downshifting to first until I get a fix for this annoying problem. Any ideas? I did take the clutch slave cylinder apart to inspect it. It looked fine to me.
-You say "I've started stopping in 2nd gear Ang then downshifting to 1st." I don't understand how that is possible without the bike stalling, as the only gear that the AE will allow go into a 'neutral/stopped' state while the engine is running id 1st gear. Rolling to a complete stop in 2nd should cause the engine to stall.-Re the slave cylinder that eventually got replaced: like with yours, it appeared fine upon initial teardown and inspection. But clearly it was not okay. The problem with the seal was obviously something my naked eye couldn't discern.
You can stop in 2nd gear and the bike will idle. Never heard any different and I know others who do the same thing. What was it about the slave cylinder that constituted replacing it? Is there something to look for? Thanks.
Ok on the soak. Didn't sound quite right, but I thought I'd ask.

I will re-affirm FJRPittsburg's statement about stopping in second. Assuming your bike has no problems, you can stop in ANY gear, bike will not stall. You can attempt to move off from rest in ANY gear, bike will not stall (but may not move from rest very quickly!).
I guess the only time(s) I remember stopping while in a gear other than 1st have been those occasions where an error code was in play (a few time with SH_26 and likewise with SH_46). In those cases, the engine would always stall out at around 3 or 4 mph or thereabouts. So, after reading these replies (about being able to stop while in any gear without the engine stalling) I tried stopping the bike in 2nd gear (with no error code)... and I was able to do that. So, my previous statement was incorrect (about not being able to stop the bike in a gear other than 1st without it causing the engine to stall).

 
Here's an update to the issue on my '08 AE…

I purchased a new slave cylinder kit, a master cylinder rebuild kit, as well as a fresh hydraulic hose. They are currently sitting on my work bench awaiting for me to make some time to install before the weather sets in - I ride all year here in the San Jose Bay Area. In the mean time I had another issue that popped up on my ride home from EOM last September. just heading west out of Gallup NM, the alarm code SHIFT 37 came up on my dash with the yellow light. I had spent the last 24 hours on the road driving through some heavy rain without an issue, but I suspected some sort of electrical issue. I called my buddy Victor in Florida, and he checked his shop manual. SHIFT 37 is triggered by the power supply to the clutch or shift actuator motor being abnormal. The battery voltage is good, but the motor terminal voltage is too low.

Since the sun was just setting, and I was at freeway speed in fifth gear, and I had just passed the last exit and was heading off into the wilderness - without the ability to shift gears, I decided to head toward Flagstaff instead of Phoenix; I could make it with the fuel I had on board if I slowed down a bit. Let me tell you, 55 miles per hour on one of these Sport Touring rocket ships, on the interstate, with everybody blowing on by you - especially the 18 wheelers was no fun, but I dared not stop along the side of the road because SHIFT 37 not only disabled the shifting, it will not let you start the bike up again. At least in Flagstaff there was a Motel 6 right at the east end of town, and possibly an open Yamaha shop in the morning.

I made it to Flagstaff, took the up hill offramp, in 5th gear, and wouldn't you know it, the light turned red just as I arrived at the right turn. Nobody was coming so I chugged around the turn at around 900 rpm and just made into the Motel 6 parking lot as the bike stalled. Remember, the electric shift was not working so the clutch was never engaged. I turned off the key, put the bike up on center stand, and was about to hand shift the gear box into neutral when just for kicks I turned the key back on.

What's this? No SHIFT 37 alarm. 

I pulled in the front brake and hit the paddle and it kicked into 4th gear !!! COOL, so I shifted all the way into neutral, and there was no indication of any abnormality. What the heck, I got back on the bike, headed to the Chevron station across the street and got some gas, then got back on the freeway and headed toward my sister's house near San Diego. 

Only one other time since then did the SHIFT 37 show up, and that was after some heavy rain on my commute here in the San Jose Bay Area. Since this bike is my main transportation, my bride drives the Subaru, I figured now was a good time to look into the bike's electrical connections. My other two FJRs had dielectric grease applied to their connectors, but this time around I tried ACF-50. It had been about 5 years since I did it, and in some of the more exposed connectors the ACF-50 had washed out. So last week I dove into the bowels of my bike to gain access to all the connectors to apply the dielectric grease. For some reason I pulled out the shift mechanism and noticed the a broken plastic terminal off the side of it. It was hard plastic, kind of like bakelite, and inside I could see the two thin strips of metal with which wire harness wires were bonded. This must be the smoking gun that triggered the SHIFT 37 alarm. They had gotten wet, and with all the contaminates, some of the voltage must have bled across or bled away, and the black box electronics must have sensed it. Driving from Gallup to Flagstaff with no rain must have dried out the broken plastic area and restored the available voltage. When I turned off the key at the Motel 6 parking lot it must have reset the electronics, and no more problem.

E-Bay to the rescue. For the princely sum of $80 (with free shipping from north Carolina), I now have another shift actuator with linkage. I'm holding off putting it in because I had made a repair with some really good sealant gooped on to the broken plastic, so lets see how long it will serve.

Brodie

🙂

 
Sh 37 is not one I'd heard of. I can only assume that there was dirt on the exposed connections which, when wet, allowed significant current to flow when none was expected. Water on its own won't leak electricity enough to cause the computer to throw a hissy fit. Does your "all seasons" riding take you along salted roads? Wet salty dirt will certainly leak detectable amounts of juice.

Of course, if there is corrosion in there, anything could happen. 

Anyway, glad you got out of the situation ok (and without a ticket for running a red light - it's amazing how many thoughts go through your head in a very short period of time when faced with that sort of situation). 

 
Top