Clunking When First Starting

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I'll check tomorrow morning. Rode to work this morning, but didn't pay attention to the noise.

Ian,

don't bother to change your starting habit, just hold the front brake on while you release the clutch. Then you are covered regardless of any malfuntion. That is how I start my FJR each and every time.

Slardy

 
I was taught to hold the clutch lever in and hold the front brake lever in when starting the bike, and then slowly release the clutch lever to ensure the bike isn't in gear/malfunctioning. I still do it, and have been doing that for years. I might not "need" to, but I do. Sure, the bike has lights and safety systems... but they fail. I figure as the bike and I get older, my habits will still be in practice, and may just prevent (at least) an embarrassing moment.

 
Odd. I had figured it was normal, but I am now trying to visualize what is happening when there is a misfire. What in the world is causing that "thud" every so often?
Mine has always done this as well. It stops making the banging sound as soon as the clutch is disengaged so I'm pretty sure the noise is coming from the backlash in the gears in the tranny when the engine is miss-firing. Pull in the clutch and the tranny stops spinning, or should if you have well soaked clutch plates.

 
I think mine does the same as you are describing. It makes some banging noises when first started up, sounds like it's misfiring some and trying to turn the engine backwards (don't think so). Goes away after less than a minute. I wrote it off to a big engine warming up. Never gave it a thought after the first couple of starts and it didn't come apart.
Big cams and a cold engine?
It is normal. I believe that it's a misfire caused by the cold start circuit. (running rich) until it warms up.
My 2007 does the same thing. It has nothing to do with drivetrains,transmission,clutch etc.

They are running lean. Thats why it is making the "popping" noise. All the more reason to let the bike warm up before going out and floggin it.

The OEMs have these bikes mapped lean I guess for emissions...mileage?? ,but it sure does create drivability issues. Had the same problems when I was

working as an automotive tech. in the 80s. We were setting COs up all the time on EFI and carbed cars all the time because the were way too lean from the factory.

 
Folks,

As I stated in the earlier message, I was going to do the BARBARIAN mode and play with it.

The mod was very easily done and I increased the CO setting in cylinders 1 and 2.

Since then, I have cold started the engine 3 times and the misfire has not reoccurred. :D

Slardy

 
I have an 08 and it often does the clunk when starting cold. I did the Barbarian Mod just 2 months ago and increased all cylinders by 7 as recommended. Still clunks, but not going to worry about it. Bike has 6000 miles.

Good luck in figuring this whole thing out but it doesn't sound like it is much to worry about from others.

 
The noise that we all hear are from the automatic choke, warm-up injector, knocking due to extra fuel during warm-up, solenoids and relays etc.. that is trying to maintain the idle during cold starting. After it warm-up the noise is gone. It is the nature of the beast, so don't go and do something crazy like tune-up, replacing spark plugs, or worst jet soaking the clutch.

 
My ST1100 did it, and my FJR does it. A fellow rider who I respect as a mechanic told me years ago "don't worry about it". I stopped worrying and life is good. The FJR still clunks.

 
The noise that we all hear are from the automatic choke, warm-up injector, knocking due to extra fuel during warm-up, solenoids and relays etc.. that is trying to maintain the idle during cold starting. After it warm-up the noise is gone. It is the nature of the beast, so don't go and do something crazy like tune-up, replacing spark plugs, or worst jet soaking the clutch.
You aren't serious, are you?

 
The noise that we all hear are from the automatic choke, warm-up injector, knocking due to extra fuel during warm-up, solenoids and relays etc.. that is trying to maintain the idle during cold starting. After it warm-up the noise is gone. It is the nature of the beast, so don't go and do something crazy like tune-up, replacing spark plugs, or worst jet soaking the clutch.
You aren't serious, are you?
My brand new FJR make the same noise. My 1995 honda made those noises for the last 10 years and still making the noise. Nearly everyone said their bikes make the same noise during warm up. So I am serious. The noise is normal. Don't do anything, else they might find themself in a jam.

 
The noise that we all hear are from the automatic choke, warm-up injector, knocking due to extra fuel during warm-up, solenoids and relays etc.. that is trying to maintain the idle during cold starting. After it warm-up the noise is gone. It is the nature of the beast, so don't go and do something crazy like tune-up, replacing spark plugs, or worst jet soaking the clutch.
You aren't serious, are you?
My brand new FJR make the same noise. My 1995 honda made those noises for the last 10 years and still making the noise. Nearly everyone said their bikes make the same noise during warm up. So I am serious. The noise is normal. Don't do anything, else they might find themself in a jam.
The FJR has a fuel injected engine. It does not have an "automatic choke" or a "warm up injector", nor does it have any relays or solenoids that make knocking sounds during warm up.

What it does have is a temperature sensor and an ECU (Electronic Control Unit) that enrichens the fuel mixture during engine warm up.

But you are correct about one thing. It is "normal".

 
The FJR has a fuel injected engine. It does not have an "automatic choke" or a "warm up injector"What it does have is a temperature sensor and an ECU (Electronic Control Unit) that enrichens the fuel mixture during engine warm up.
The FJR fuel injection throttle bodies have cold-start fast idle (choke) pistons on each TB -- similar to what's on Mikuni carbs/carb sets.

As with Mikuni carbs, if the idle speed isn't near the correct setting or if you open the throttle butterflys (when attempting cold-start), you may defeat the idle by-pass (choke) operation by inducing extra airflow (mis-directing air intended for cold-start piston assys).

There have been start-up 'noises' reported -- some attributed to cold, warming-up, cat/cons.

 
The FJR fuel injection throttle bodies have cold-start fast idle (choke) pistons on each TB -- similar to what's on Mikuni carbs/carb sets. As with Mikuni carbs, if the idle speed isn't near the correct setting or if you open the throttle butterflys (when attempting cold-start), you may defeat the idle by-pass (choke) operation by inducing extra airflow (mis-directing air intended for cold-start piston assys).
Hmmm... really? I have never heard of (or seen) these fast idle pistons in the throttle bodies. Are you sure about that?

Funny that the factory Service Manual wouldn't show them, or talk about them.

Is this a Friday joke?

You aren't referring to the Air Induction system, are you? Cause that goes no where near the throttle bodies.

 
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The FJR fuel injection throttle bodies have cold-start fast idle (choke) pistons on each TB -- similar to what's on Mikuni carbs/carb sets. As with Mikuni carbs, if the idle speed isn't near the correct setting or if you open the throttle butterflys (when attempting cold-start), you may defeat the idle by-pass (choke) operation by inducing extra airflow (mis-directing air intended for cold-start piston assys).
Hmmm... really?
Yep.

I have never heard of (or seen) these fast idle pistons in the throttle bodies.
Well, you may need to get in there and look...? :unsure:

Are you sure about that?
Yep.

Funny that the factory Service Manual wouldn't show them, or talk about them.
No-one ever brags about the efficacy of the FSM.

Is this a Friday joke?
Nope.

You aren't referring to the Air Induction system, are you? Cause that goes no where near the throttle bodies.
No, I know the difference. (Was that a Friday joke...?) :huh: :)

 
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OK, I'll take your word for it. (And no, it was not a Friday joke.)

So what actuates these "fast idle" pistons? A solenoid? Never noticed one in the wiring diagram.

 
So what actuates these "fast idle" pistons? A solenoid? Never noticed one in the wiring diagram.
Looks like a vacuum device, to me -- but, I haven't made a 'study' of it....

And, you're right, I don't think the FSM addresses it? Neither is there any device, solenoid or servo-motor, to account for the extra 1K rpm (or so) at start-up. Nothing rotates the butterflys.....

 
So what actuates these "fast idle" pistons? A solenoid? Never noticed one in the wiring diagram.
Looks like a vacuum device, to me -- but, I haven't made a 'study' of it....

And, you're right, I don't think the FSM addresses it? Neither is there any device, solenoid or servo-motor, to account for the extra 1K rpm (or so) at start-up. Nothing rotates the butterflys.....
Good point.

 
The noise that we all hear are from the automatic choke, warm-up injector, knocking due to extra fuel during warm-up, solenoids and relays etc.. that is trying to maintain the idle during cold starting. After it warm-up the noise is gone. It is the nature of the beast, so don't go and do something crazy like tune-up, replacing spark plugs, or worst jet soaking the clutch.
I not sure that I agree, ttooee. I don't believe any of those items would result in the entire bike shuttering. My misfiring stopped after recently increasing the CO in cylinders 1 & 2, the side of the engine that the noise was most noticeable. If the misfire just caused a popping noise, I could ignore it. But it shakes the entire bike and I can only imagine the stresses on the cam chain, crankshaft, pistons, etc. on the engine that is not fully warmed up. That is why I decided to something about it.

Slardy

 
Slardy,

Same thing here. '04 was smooth as silk both start and shifting. The '08 has the same funky cold startup issues. The shifting is starting to smooth out but have the clutch cover gasket in case.

I really liked the updates for the 08 so have been putting up with the few quirks. If given the option to get back the 04, i'd keep the 08 and keep working out the bugs.

terrysig

 
Slardy,
Same thing here. '04 was smooth as silk both start and shifting. The '08 has the same funky cold startup issues. The shifting is starting to smooth out but have the clutch cover gasket in case.

I really liked the updates for the 08 so have been putting up with the few quirks. If given the option to get back the 04, i'd keep the 08 and keep working out the bugs.

terrysig
Same here with the 04. The 08 clunks at cold start up. I thought about messing with the CO settings, but haven't yet. Don't know if I believe it will help. I did bump up the idle a little because it was a little low. Seems like that helped a little. Given the choice to get back the 04 or keep the 08 would be a little tougher for me. I really liked how the 04 ran and shifted and handled and .................. Well anyway thats past history. If I can get rid of or reduce the bugs on the 08, I'll be happy.

GP

 
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