Very rough, nearly stalls, at idle

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Recently I've been noticing a problem that's been getting worse. This is on a 2008 FJR1300A with 3000 miles on it (it's three months old). When I start letting out the clutch from a stop in first gear, there's a very rough sort of scratching sound and the engine slows down more than it should; I have to give it plenty of gas to avoid a stall. It seems to go away once I get moving. The problem only happens if the bike's been still for a bit, such as waiting at a traffic light, and even then I think it only happens when the engine is at least somewhat cool.

Perhaps more telling, today I couldn't even start it without twisting the throttle to force extra gas in. It was 80 degrees out and the bike was sitting parked for only a half-hour since I was having lunch. Got back, pressing the starter button, and the engine did not fire up even with my holding the button for several seconds. But as I mentioned, twisting the throttle plenty while pushing it got it going.

So I'm quite sure these are both symptoms of the same problem and the starter issue means it isn't the clutch. So what could it be?

Oh, and the idle has been a bit rough for some time. It never goes below 1100 rpm, but it constantly wavers between like 1400 rpm and 1100 rpm. You can easily hear the engine constantly firing then not firing. I did a throttle-body sync at 600 miles, though they were in spec so I didn't actually adjust anything, but one cylinder had seemed slightly behind the others.

 
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Take it to the dealer and let them fix it. You're bike is still under the 1 year factory warantee. For what it's worth, sounds like a vacuume leak to me. Not that my opinion is worth much mind you :p

 
Don't ride it anymore! Sounds like a bearing gone on the trans input. It could be so far gone that the friction is screwing with the idle. In any case, DO NOT RIDE as complete failure could mean major repairs on the bike-and you.

 
Check the forum about the throttle position sensor, that has been recalled.

Also, is your bike an AE model?

If so maybe it's just the sensor, it might be that vital to the operation of the automatic clutch?

Of course I could be way wrong here.

 
Don't ride it anymore! Sounds like a bearing gone on the trans input. It could be so far gone that the friction is screwing with the idle. In any case, DO NOT RIDE as complete failure could mean major repairs on the bike-and you.
Are you sure? I rode a lot this past weekend with no problems, but the bike was always warmed. The problem happened the most today on my lunch break when I was doing very short hops then parking.

Also if it wasn't clear, there's no weird sound when idling, the engine just surges a bit. And it did that, though to a slightly lesser degree, since day 1 (0 miles); it has never been a completely steady idle.

My bike's the normal (A as in ABS) model.

 
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Are you sure? I rode a lot this past weekend with no problems, but the bike was always warmed. The problem happened the most today on my lunch break when I was doing very short hops then parking.
Aren't you going to have problems walking straight now that one of your legs is distinctly longer than the other? And Radman didn't even have to yank on it, just pull with a little pressure and..... :rolleyes:

It's back to the dealer for you! Let them troubleshoot the problem. My guess is a bad TPS or a vacuum leak. Either way, that's what the 1 yr. warranty is for.

 
Damn you, I was getting really nervous and refreshing manically. :dribble:

By the way, after I was done replacing a fairing I'd damaged in a gentle lay-down (the upper left fairing so the entire front end had to go), I had a dark brown rubber grommet left over. I never removed it but I found it lying under the bike and am quite sure it came from the bike and fell off sometime then. I'll post a picture in a couple of hours when I get home, but it's an end cap; it's a half-dome on one side and the other part clearly plugs into an opening somewhere. It's relatively large, not the little vacuum caps that go over the throttle bodies if that's what you're thinking. I'm guessing it's just for vibration dampening somewhere.

 
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Damn you, I was getting really nervous and refreshing manically. :dribble:
By the way, after I was done replacing a fairing I'd damaged in a gentle lay-down (the upper left fairing so the entire front end had to go), I had a dark brown rubber grommet left over. I never removed it but I found it lying under the bike and am quite sure it came from the bike and fell off sometime then. I'll post a picture in a couple of hours when I get home, but it's an end cap; it's a half-dome on one side and the other part clearly plugs into an opening somewhere. It's relatively large, not the little vacuum caps that go over the throttle bodies if that's what you're thinking. I'm guessing it's just for vibration dampening somewhere.
Wild guess says look in your glovebox. There's a grommet at the very bottom that tends to fall out when I work on the left side of the bike.

 
I think that one's different and is for liquids that get inside the compartment... I'm pretty certain that stayed on.

Here are pictures. It looks 3/8" or 1/2" high, for size reference.

Grommet1.jpg
Grommet2.jpg


 
It looks more like a rubber bumper for something. Kickstand???

One of the snubbers that keep the radiator from bouncing/vibrating?

 
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One of the snubbers that keep the radiator from bouncing/vibrating?
Looks like you solved that little mystery! I checked the parts diagram for the radiator and can see it, there is only one of them and it's attached to the "radiator stay". It is #24 here (radiator cover is on the bottom, radiator itself is on the top):

Grommet.jpg


Putting it back would involve removing some fairings again. Bleh. What's this for anyway? Preventing the lower fairing from hitting it?

 
Subscribed...

I have an '08 that I bought in September. I have the same symptoms when I start it after a short rest stop and the engine is still warm.

 
It was the scratchy noise when using the clutch that concerned me. The more I thought about it, the less it seemed a input bearing and more like a clutch beginning to come apart. But as always, trying to diagnose without having the bike in front of me bites again.

 
I have an '08 that I bought in September. I have the same symptoms when I start it after a short rest stop and the engine is still warm.
How long were you riding before the rest stop? I did not seem to get the problem when riding home last night; it mainly happened after I rode literally one minute, then parked it, then tried to start it again half an hour later. Didn't turn over til I applied throttle, and had the weird scratching when starting from stops on that ride (which was itself short).

It could be a weird poorly-programmed fuel injection...?

Also I exaggerated the idle problems. It constantly wavers, and audibly, but only between like 1100-1250 rpm, so a much smaller range than what I stated.

 
Well, I'll let you know how mine turns out.

My 08 had these same symptoms right out of the box.

I first attributed it to break-in. I figured it need to be broike-in, so I waited. It got better... but not much. It was intermittent and I KNOW how hard that can be to fix... so I ignored it and hoped it would get worse and be easier to find when I took it in.

After almost 13K miles, it has not gotten any better and the other day was the final straw. We had VERY nice weather and the bike had been outside work for about 3 hours in the sun and 78 degree weather and I tried to start it. Same crap, wouldn't start until I cracked the throttle. Then it stumbled until I blipped it a few times. I put the rest of my gear on and headed down the road... only to find the bike had NO power (almost like running on 2 cylinders) for the first 1/4 throttle. Go beyond that and it ran fine.

Well, this coupled with the continuous stumble while trying to ride smooth at 2-3.5K rpm and I decided to give it to the dealer and let them fix it.

I HATE taking the bike in and I hate being without it. I also HATE the idea that the other day was a preview of what to expect during the next 9 months of warm riding weather!

So, I get my warranty recall done and (hopefully) a new ECU or TPS or whatever the @%$* it is that is making my second FJR run like crap. Here's keeping my fingers crossed that they will get it right. I don't doubt my dealer, they have been pretty good to me. I just know how bad it is trying to find a problem that doesn't always exist!

 
I have an '08 that I bought in September. I have the same symptoms when I start it after a short rest stop and the engine is still warm.
How long were you riding before the rest stop? I did not seem to get the problem when riding home last night; it mainly happened after I rode literally one minute, then parked it, then tried to start it again half an hour later. Didn't turn over til I applied throttle, and had the weird scratching when starting from stops on that ride (which was itself short).

It could be a weird poorly-programmed fuel injection...?

Also I exaggerated the idle problems. It constantly wavers, and audibly, but only between like 1100-1250 rpm, so a much smaller range than what I stated.
It seems to happen when I stop longer than a few minutes and now remember after reading Duff's response that it happened on very warm days when the bike sat in the sun for a while.

Silent helped me install a PCIII (thanks again Silent :clapping: ) and that definitely helped, but it still happenes from time to time.

 
Well, I'll let you know how mine turns out.
My 08 had these same symptoms right out of the box.

I first attributed it to break-in. I figured it need to be broike-in, so I waited. It got better... but not much. It was intermittent and I KNOW how hard that can be to fix... so I ignored it and hoped it would get worse and be easier to find when I took it in.

After almost 13K miles, it has not gotten any better and the other day was the final straw. We had VERY nice weather and the bike had been outside work for about 3 hours in the sun and 78 degree weather and I tried to start it. Same crap, wouldn't start until I cracked the throttle. Then it stumbled until I blipped it a few times. I put the rest of my gear on and headed down the road... only to find the bike had NO power (almost like running on 2 cylinders) for the first 1/4 throttle. Go beyond that and it ran fine.

Well, this coupled with the continuous stumble while trying to ride smooth at 2-3.5K rpm and I decided to give it to the dealer and let them fix it.

I HATE taking the bike in and I hate being without it. I also HATE the idea that the other day was a preview of what to expect during the next 9 months of warm riding weather!

So, I get my warranty recall done and (hopefully) a new ECU or TPS or whatever the @%$* it is that is making my second FJR run like crap. Here's keeping my fingers crossed that they will get it right. I don't doubt my dealer, they have been pretty good to me. I just know how bad it is trying to find a problem that doesn't always exist!
=======

..... ;>

MIGHT BE OPERATOR ERROR DUFF............... Just kiddin :rolleyes: :dribble:

B.

 
Recently I've been noticing a problem that's been getting worse. This is on a 2008 FJR1300A with 3000 miles on it (it's three months old). When I start letting out the clutch from a stop in first gear, there's a very rough sort of scratching sound and the engine slows down more than it should; I have to give it plenty of gas to avoid a stall. It seems to go away once I get moving. The problem only happens if the bike's been still for a bit, such as waiting at a traffic light, and even then I think it only happens when the engine is at least somewhat cool.
Perhaps more telling, today I couldn't even start it without twisting the throttle to force extra gas in. It was 80 degrees out and the bike was sitting parked for only a half-hour since I was having lunch. Got back, pressing the starter button, and the engine did not fire up even with my holding the button for several seconds. But as I mentioned, twisting the throttle plenty while pushing it got it going.

So I'm quite sure these are both symptoms of the same problem and the starter issue means it isn't the clutch. So what could it be?

Oh, and the idle has been a bit rough for some time. It never goes below 1100 rpm, but it constantly wavers between like 1400 rpm and 1100 rpm. You can easily hear the engine constantly firing then not firing. I did a throttle-body sync at 600 miles, though they were in spec so I didn't actually adjust anything, but one cylinder had seemed slightly behind the others.



Did you have the throttle body sync done?

 
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