I purchased a 06 back in February and have since put around 800 miles on it. The problem I have been having is the bike not wanting to idle until the temperature reaches the mid point on the gauge. When you first start it, it will idle fine until it starts to warm a little. After that I have to control the throttle to make sure it won't stall. I first thought it may be happening because of the temperature outside was in the 40s but since it has been hitting 70's lately this is no longer a possibility. I was thinking the idle may need to be adjusted a bit but to my surprise the idle has been set to its highest point. When it does idle correctly it stays at around 1100. Do any of you have any ideas on what's possibly going on with it? I'm a bit disappointed because this is my first bike that I bought through a dealership and was hoping to not have to mess with it for a while. The bike almost has 12k on it if that helps diagnosis the issue. Also all the recalls have been taken care of as well.
Weird idle problem
- Thread starter towelbit
- Start date
Help Support Yamaha FJR Motorcycle Forum:
Not sure about this, but sounds to me like the throttle bodies need to be synched. Possibly, there's inadequate vacuum ( not enough Mercury being pulled, as the old saying goes). I am just a "shadetree mechanic", so I'm just guessing.
I think 15wannabe is on the right track.
If the warm idle speed can't be increased, that means that someone has previously mis-adjusted the air bypass screws (the ones that you adjust for a TBS) and closed them down too much. It's not too little vacuum that would cause this, it's too little air.
The way to fix that would be to open all four of the air screws an equal amount, but more than they are now, re-adjust your idle speed (down now because of the added air from the air screws) and then balance as normal. To find a good value to open them all up to just count how many turns it takes to close them each down to lightly seated, then open them all to the largest one plus 1/2 a turn.
If you are feeling more adventurous you could follow my RDCUA TBS procedure, which has you close down all 4 screws and adjust the linkage to get equal vacuum, then open them all the same and sync them from there.
You want the warm idle speed to be 1100rpm, no lower. And you want the idle adjuster to be somewhere in mid-range, with the ability to increase and decrease the idle speed from 1100.
If cold idle is erratic after all the above is working well, the fast idle mechanism may be gummed up. There is a wax motor under the throttle bodies that drives the mechanism, and four piston type actuators (one in each body) with linkage from the wax ,motor to drive them. There is also an adjustment screw, so if you knew the linkage was working right, you could raise the cold idle speed, but the whole thing is pretty hard to get at with the throttle bodies in place.
If the warm idle speed can't be increased, that means that someone has previously mis-adjusted the air bypass screws (the ones that you adjust for a TBS) and closed them down too much. It's not too little vacuum that would cause this, it's too little air.
The way to fix that would be to open all four of the air screws an equal amount, but more than they are now, re-adjust your idle speed (down now because of the added air from the air screws) and then balance as normal. To find a good value to open them all up to just count how many turns it takes to close them each down to lightly seated, then open them all to the largest one plus 1/2 a turn.
If you are feeling more adventurous you could follow my RDCUA TBS procedure, which has you close down all 4 screws and adjust the linkage to get equal vacuum, then open them all the same and sync them from there.
You want the warm idle speed to be 1100rpm, no lower. And you want the idle adjuster to be somewhere in mid-range, with the ability to increase and decrease the idle speed from 1100.
If cold idle is erratic after all the above is working well, the fast idle mechanism may be gummed up. There is a wax motor under the throttle bodies that drives the mechanism, and four piston type actuators (one in each body) with linkage from the wax ,motor to drive them. There is also an adjustment screw, so if you knew the linkage was working right, you could raise the cold idle speed, but the whole thing is pretty hard to get at with the throttle bodies in place.
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12k miles isn't a lot so it's a long shot, but do you know if the dealership or previous owner did a valve check? Things you describe are several classic symptoms of the timing chain being one tooth off on the crankshaft sprocket.
I was thinking this may be my next route. The fast idle mechanism is something I never considered though. Thanks for the detailed reply, hopefully I can tackle this issue this Friday.
TownsendsFJR1300
Well-known member
I worked on a Yamaha outboard engine recently that the cam belt was OFF two cogs! (non-interference engine) Still ran too!
Agreed the above is a distinct possibility however, the valve cover and RS cover will have to come off to verify markings.
For the op, do you know if the CCT has been changed out? .
<blockquote class='ipsBlockquote'data-author="TownsendsFJR1300" data-cid="1228122" data-time="1430952365"><p>
<blockquote class='ipsBlockquote'data-author="rbentnail" data-cid="1228013" data-time="1430920571"><p><blockquote class='ipsBlockquote'data-author="towelbit" data-cid="1227969" data-time="1430885021"><p> I was thinking the idle may need to be adjusted a bit but to my surprise the idle has been set to its highest point.</p></blockquote>
12k miles isn't a lot so it's a long shot, but do you know if the dealership or previous owner did a valve check? Things you describe are several classic symptoms of the <strong class='bbc'>timing chain being one tooth off on the crankshaft sprocket.</strong></p></blockquote>
I worked on a Yamaha outboard engine recently that the cam belt was OFF two cogs! (non-interference engine) Still ran too! <br />
<br />
Agreed the above is a distinct possibility however, the valve cover and RS cover will have to come off to verify markings.<br />
<br />
For the op, do you know if the CCT has been changed out? . </p></blockquote>
For this I have no idea. The only information about the bike that I have is what the dealership has done to it while it was there. Which is bolts, mirror, and an oil change. I sure hope I don't have to take the valve cover off. I should know more Friday when I synch the throttle bodies. If the problem still exists I'll start looking into this some more.
<blockquote class='ipsBlockquote'data-author="rbentnail" data-cid="1228013" data-time="1430920571"><p><blockquote class='ipsBlockquote'data-author="towelbit" data-cid="1227969" data-time="1430885021"><p> I was thinking the idle may need to be adjusted a bit but to my surprise the idle has been set to its highest point.</p></blockquote>
12k miles isn't a lot so it's a long shot, but do you know if the dealership or previous owner did a valve check? Things you describe are several classic symptoms of the <strong class='bbc'>timing chain being one tooth off on the crankshaft sprocket.</strong></p></blockquote>
I worked on a Yamaha outboard engine recently that the cam belt was OFF two cogs! (non-interference engine) Still ran too! <br />
<br />
Agreed the above is a distinct possibility however, the valve cover and RS cover will have to come off to verify markings.<br />
<br />
For the op, do you know if the CCT has been changed out? . </p></blockquote>
For this I have no idea. The only information about the bike that I have is what the dealership has done to it while it was there. Which is bolts, mirror, and an oil change. I sure hope I don't have to take the valve cover off. I should know more Friday when I synch the throttle bodies. If the problem still exists I'll start looking into this some more.
ionbeam
2 FUN
Given your symptoms please follow Fred W's advice first, you have the classic symptoms of a TBS gone wrong. Then, if that doesn't resolve your problems move on to other suggestions.
I do recall one of the symptoms of the cam chain being off by one tooth being the inability to idle well. That would make a lot of sense if the chain skip makes the valve timing earlier than normal. But I do not recall that particular symptom being affected by how warm the engine is.
If I read the OP lines correctly, the engine does idle OK after it has warmed up, right?
How does it run otherwise once it is warmed up fully? OK? Or sluggishly? Or maybe the bike too new to you for you to say for sure?
If I read the OP lines correctly, the engine does idle OK after it has warmed up, right?
How does it run otherwise once it is warmed up fully? OK? Or sluggishly? Or maybe the bike too new to you for you to say for sure?
Denver_FJR
Well-known member
You can see a portion of the fast idle mechanism below and on the left side of the intake manifold. You should also be able see it move (slightly) as engine warms and manually engage it as well.
RaYzerman19
Go Wings!
An '06 with 12k..... a bit unlikely that the cam chain has skipped a tooth, and the symptoms indicate a TBS issue. It may have never had one....... the FSM procedure says sync to throttle body #3, but I've found several where the #3 air screw was too far in, as well as the other 3, and idle speed can be erratic/proper idle not attainable. In your case, the simplest thing to do is to screw in all 4 screws fully (and lightly so not to damage the seats), and make note of the number of turns for each (they all are likely less than 3/4 turn given your symptoms). The FSM says if the screws were previously removed, they should be set at 3/4 turn (out from seated). From my experience (and IRCC, Fred's unauthorized procedure), the suggested setting is one turn out (no more) as a starting point for the TBS. If you do nothing else, then you now should be able to adjust the idle to 1100 rpm after the engine is fully warmed up. It should run OK, however, that does not guarantee sync'd throttle bodies, so a TBS should be done after that to smooth out vibrations, etc. that may be apparent during riding.
PS - why not visit the pit crew at the WNYFJR tech day on June 6.......
PS - why not visit the pit crew at the WNYFJR tech day on June 6.......
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TownsendsFJR1300
Well-known member
I agree, checking the TBS screws/sync would be the first I would check. Its easy enough and as posted previously, if you run out of adjustment, open the primary screw 1/4 turn. That will give you more adjustment on the other three cylinders.
I also agree 12,000 miles is super low (and NOT likely) for a CCT failure BUT you don't know who's been in the motor or done what.
**There was a member here, maybe a year or two ago, who's chain jumped (I think he was doing a valve check/adjustment). The bike was fairly new to him and the bike didn't run right. He eventually pulled the valve cover/side cover and found the chain off a tooth. Still ran, just crappy.. Ran great after the fix.
I've had, under warranty, (when the Gen l's (2004) under tank harness corroded and caused issues), a Yamaha dealership sync my engine (before I had a Carbtune). The dealership ADJUSTED the white painted spring BUTTERFLY SCREW, not the air screw (approx 1/4 turn). You could see the broken paint and the original position. After I got the carbtune(really for my FZ), I checked the FJR and found the adjusted butterfly screw. I put that back to its original position and adjusted the air screws as it should have been to start with.
BTW, they couldn't find the issue, I found it here, posted by other members in 2005 or so...
Point being, even thou a licenced Yamaha dealership did the warranty work, it was DONE INCORRECTLY and the problem wasn't even fixed by them... If they did a sync, check valves, etc, its not neccessarily been done right, unfortunatly..
I also agree 12,000 miles is super low (and NOT likely) for a CCT failure BUT you don't know who's been in the motor or done what.
**There was a member here, maybe a year or two ago, who's chain jumped (I think he was doing a valve check/adjustment). The bike was fairly new to him and the bike didn't run right. He eventually pulled the valve cover/side cover and found the chain off a tooth. Still ran, just crappy.. Ran great after the fix.
I've had, under warranty, (when the Gen l's (2004) under tank harness corroded and caused issues), a Yamaha dealership sync my engine (before I had a Carbtune). The dealership ADJUSTED the white painted spring BUTTERFLY SCREW, not the air screw (approx 1/4 turn). You could see the broken paint and the original position. After I got the carbtune(really for my FZ), I checked the FJR and found the adjusted butterfly screw. I put that back to its original position and adjusted the air screws as it should have been to start with.
BTW, they couldn't find the issue, I found it here, posted by other members in 2005 or so...
Point being, even thou a licenced Yamaha dealership did the warranty work, it was DONE INCORRECTLY and the problem wasn't even fixed by them... If they did a sync, check valves, etc, its not neccessarily been done right, unfortunatly..
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*update* So last night I followed your RDCUA TBS procedure (awesome write up by the way) and found the air bypass screws were set at 1 3/4 turns. After synchronizing I ended up putting them 2 full turns out equally after setting them to zero. I will say that the bike seems to run smoother but I wanted to wait till the next day to see how it runs when cold. Unfortunately today I discovered the problem is still there. So now I have a few questions: 1) Is two turns out too much for the air screws? 2) When you turn your idle adjustment all the way up, what is the RPM you're getting? 3) Is there a write up on here on how to get at/ work on this idle mechanism? I think that may be the issue now. The cold Idle is a little erratic but its hard to tell since it doesn't really idle after the "choke" shuts off and goes to normal operation. Once the bike is warm, it idles fine like before but a bit smoother than before.
TownsendsFJR1300
Well-known member
I would think the "standard" setting is in the shop manual.
For my FZ6 (it has a separate "block" with ALL the screws adjacent to each other-see below).
in that manual, its 3/4 a turn out from lightly seated. Lack of adjustment issues for the other cylinders, the base is screw is opened usually no more than another 1/4 (or 1 turn
total)...
______________________________________________________________________________________
From the FZ6 manual
For my FZ6 (it has a separate "block" with ALL the screws adjacent to each other-see below).
in that manual, its 3/4 a turn out from lightly seated. Lack of adjustment issues for the other cylinders, the base is screw is opened usually no more than another 1/4 (or 1 turn
total)...
______________________________________________________________________________________
From the FZ6 manual
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Queensland Ken
Well-known member
Have you checked the cold/fast idle function, fast idle valves ?
Cold/fast idle has a separate idle adjustment, under and behind the throttle bodies.
You can set cold/fast idle speed, there is an adjuster on the wax motor / plunger, need a 14" screwdriver.
Can only be adjusted while the motor is cold, so you don't have long to do it until the coolant heats the wax motor.
Also check the function of the valves, move that plate that controls the valves.
Cold/fast idle has a separate idle adjustment, under and behind the throttle bodies.
You can set cold/fast idle speed, there is an adjuster on the wax motor / plunger, need a 14" screwdriver.
Can only be adjusted while the motor is cold, so you don't have long to do it until the coolant heats the wax motor.
Also check the function of the valves, move that plate that controls the valves.
