Hard to Start Episode

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brazos parker

What??
Joined
Jun 24, 2005
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Location
Johnson City, TN
I haven't ridden my bike in about a week after changing oil & filter. It's raining today so I thought I'd go out and start the bike in the garage...instead of just sitting on it and making VROOM-VROOM noises. It didn't start on the first try and sounded kinda funny. It has a low level in the gas tank since I'm planning to take it to the dealer soon to get the TPS replaced (recall). I tried a second time...cough, cough, hack, hack...but no start. Same thing on the third try.

Then, I twisted the throttle wide open and tried again. It started up like it always has. Ran fine. I let it run up to 2 bars.

Is this one of the symptoms of a bad TPS? or, something else?

 
After seeing this happen numerous times, to various bikes, the following seems to apply.

1)Won't start or starts rough and dies.. These bikes have a very rich cold start cycle, if started cold then shut off before fully warmed up, a lot of unburned fuel remains in the chambers, the next cold start tends to flood them, hence the no-start or poor running scenario. Whenever they don't light off cold, or start rough and die, the open throttle (wide open is best) trick almost always gets them going. Wide open throttle reduces injector flow to minimum or off.

2)Low battery voltage. After sitting a long while, the battery is low, same problem/solution as above. Less likely if battery kept up to par.

3)Hard start hot, runs rough for a minute or two, then clears up. Starts good cold, maybe even better than normal. Classic failed fuel pressure regulator indicator. Remove vacumn line and look for wetness/fuel odor.

4)Long crank time cold. Time for fresh plugs.

5)Long crank time hot. Injector leak down, or possible fuel rail boiling if hot ambient temp and hard run prior to shut down. Cycle key on, wait till fuel pump shuts off, then key off and on again. Do several times-this will repressurize the rail, and get some cooler fuel in there. Letting bike idle for a minute or two before shut off when at a fuel stop etc, anytime the bike is to be re-started before having had a chance to cool down, will help prevent this.

Just a few suggestions one may find helpful.

 
Last edited by a moderator:
Thanx, Rad. I think #1 is most likely in my case. I just returned from a 2100 mile trip, changed the oil & filter. Started the bike cold (55 degree garage) a couple of time to circulate the oil, then let it sit for a week.

I've started it several more times today w/ no problem. Dealer was closed today but I'm calling tomorrow to schedule the TPS replacement...just in case.

 
I haven't ridden my bike in about a week after changing oil & filter. It's raining today so I thought I'd go out and start the bike in the garage...instead of just sitting on it and making VROOM-VROOM noises. It didn't start on the first try and sounded kinda funny. It has a low level in the gas tank since I'm planning to take it to the dealer soon to get the TPS replaced (recall). I tried a second time...cough, cough, hack, hack...but no start. Same thing on the third try.
Then, I twisted the throttle wide open and tried again. It started up like it always has. Ran fine. I let it run up to 2 bars.

Is this one of the symptoms of a bad TPS? or, something else?
Hey Mike,

How's it going? I had the same problem a while back with the same ultimate cure...hold the throttle wide open and crank the hell out of it.

I doubt if the hard starting is a symptom of a bad TPS. A few weeks ago IONBEAM posted an EXCELLENT step by step of how to get into the Diagnostic screen which comes up on your right hand gauge. You can even test the TBS right there with the diag screen. Its so easy even a cave man can do it! I'm sure you can find it with a "search".

The most common symptom of a bad TPS is a missing, stumbling, or flat spots as you roll on the gas, as opposed to a smooth throttle response and power increase. The flat spots would be in the same throttle position.

The TPS recall pertains to specific VIN's. My '05 wasn't listed. The effected VIN's are also listed somewhere on this forum.

Charlie

 
I haven't ridden my bike in about a week after changing oil & filter. It's raining today so I thought I'd go out and start the bike in the garage...instead of just sitting on it and making VROOM-VROOM noises. It didn't start on the first try and sounded kinda funny. It has a low level in the gas tank since I'm planning to take it to the dealer soon to get the TPS replaced (recall). I tried a second time...cough, cough, hack, hack...but no start. Same thing on the third try.

Then, I twisted the throttle wide open and tried again. It started up like it always has. Ran fine. I let it run up to 2 bars.

Is this one of the symptoms of a bad TPS? or, something else?
Hey Mike,

How's it going? I had the same problem a while back with the same ultimate cure...hold the throttle wide open and crank the hell out of it.

I doubt if the hard starting is a symptom of a bad TPS. A few weeks ago IONBEAM posted an EXCELLENT step by step of how to get into the Diagnostic screen which comes up on your right hand gauge. You can even test the TBS right there with the diag screen. Its so easy even a cave man can do it! I'm sure you can find it with a "search".

The most common symptom of a bad TPS is a missing, stumbling, or flat spots as you roll on the gas, as opposed to a smooth throttle response and power increase. The flat spots would be in the same throttle position.

The TPS recall pertains to specific VIN's. My '05 wasn't listed. The effected VIN's are also listed somewhere on this forum.

Charlie
Hello, Charlie

I really don't think the problem w/ hard starting was the TPS. My bike has been running fine. In an earlier post in this thread, Radman explained several problems that can lead to the experience I had. I think he diagnosed the problem I experienced accurately.

All is well here in the mountains of east Tennessee. The weather, as you probably can guess, is slowing down the riding and I'm a "waiter" again...waiting on my local dealer to get the replacement TPS from Mama Yama.

 
You guys are geniuses. This happened to me for the first time today. #1 did the trick. Maybe this is sticky worthy.

 
Last edited by a moderator:
After seeing this happen numerous times, to various bikes, the following seems to apply.
1)Won't start or starts rough and dies.. These bikes have a very rich cold start cycle, if started cold then shut off before fully warmed up, a lot of unburned fuel remains in the chambers, the next cold start tends to flood them, hence the no-start or poor running scenario. Whenever they don't light off cold, or start rough and die, the open throttle (wide open is best) trick almost always gets them going. Wide open throttle reduces injector flow to minimum or off.

2)Low battery voltage. After sitting a long while, the battery is low, same problem/solution as above. Less likely if battery kept up to par.

3)Hard start hot, runs rough for a minute or two, then clears up. Starts good cold, maybe even better than normal. Classic failed fuel pressure regulator indicator. Remove vacumn line and look for wetness/fuel odor.

4)Long crank time cold. Time for fresh plugs.

5)Long crank time hot. Injector leak down, or possible fuel rail boiling if hot ambient temp and hard run prior to shut down. Cycle key on, wait till fuel pump shuts off, then key off and on again. Do several times-this will repressurize the rail, and get some cooler fuel in there. Letting bike idle for a minute or two before shut off when at a fuel stop etc, anytime the bike is to be re-started before having had a chance to cool down, will help prevent this.

Just a few suggestions one may find helpful.
Radman,

You rock! That little trouble shooting section should be pinned or added to the facts bin!!

 
After seeing this happen numerous times, to various bikes, the following seems to apply.
1)Won't start or starts rough and dies.. These bikes have a very rich cold start cycle, if started cold then shut off before fully warmed up, a lot of unburned fuel remains in the chambers, the next cold start tends to flood them, hence the no-start or poor running scenario. Whenever they don't light off cold, or start rough and die, the open throttle (wide open is best) trick almost always gets them going. Wide open throttle reduces injector flow to minimum or off.

2)Low battery voltage. After sitting a long while, the battery is low, same problem/solution as above. Less likely if battery kept up to par.

3)Hard start hot, runs rough for a minute or two, then clears up. Starts good cold, maybe even better than normal. Classic failed fuel pressure regulator indicator. Remove vacumn line and look for wetness/fuel odor.

4)Long crank time cold. Time for fresh plugs.

5)Long crank time hot. Injector leak down, or possible fuel rail boiling if hot ambient temp and hard run prior to shut down. Cycle key on, wait till fuel pump shuts off, then key off and on again. Do several times-this will repressurize the rail, and get some cooler fuel in there. Letting bike idle for a minute or two before shut off when at a fuel stop etc, anytime the bike is to be re-started before having had a chance to cool down, will help prevent this.

Just a few suggestions one may find helpful.
Radman,

You rock! That little trouble shooting section should be pinned or added to the facts bin!!
Exactly. I was stuck and scratching my head since my FJR has always been reliable.

 
I've found that it's better to just put it on a battery tender (instead of starting it) unless you're going to actually take the bike out for at least a 30 or 45 minute ride. Otherwise not everything gets up to operating temperature and condensation doesn't burn out of the oil, exhausts, and other bits. Plus, it takes about 30 minutes or so for the bike's charging system to restore the battery from the loss it got during the start.

 
I've found that it's better to just put it on a battery tender (instead of starting it) unless you're going to actually take the bike out for at least a 30 or 45 minute ride. Otherwise not everything gets up to operating temperature and condensation doesn't burn out of the oil, exhausts, and other bits. Plus, it takes about 30 minutes or so for the bike's charging system to restore the battery from the loss it got during the start.

I agree this is ideal.

I had moved stuff around in my garage and then took off for Australia. When I got back the bike wouldn't start and a buyer is showing Saturday. Everything is working again though.

 
Well we have a pretty nice day here in Massachusetts, for mid-winter that is. I decided I need to take the opportunity for a ride since yesterdays nasty sleet and then gusty heavy rain washed away weeks worth of salt residue.

So I get ready to go and the bike cranks and cranks but won't start. I had read through various posts before including this one and remembered that WFO does the trick. But not for me today. It did cough and sputter a bit at WFO while cranking so I decided to stay with it. I ended up draining the battery to the point where cranking RPM was maybe half of normal rate. Crap, now what?

I removed the panels over the battery to expose the terminals, got out my jumper cables and hooked it up to the car battery. Cranked it for maybe 20-30 seconds and she fired up. All kinds of fumes and smoke erupted from the pipes. It smelled quite rich. In about 10 seconds it settled right down to normal cold start behavior. I let it warm a bit while I reassembled to fairing panels and finished suiting up.

I rode about 30 miles, varying speeds, etc. Shut it off a couple times and it started just fine.

I keep the battery on a tender as I have done since new 3+years ago so I don't think the battery was down when I first attempted starting. I not sure of the root cause, maybe just mid-winter blues, but just cranking the piss out it it with throttle wide open seems to be the cure.

So anyway, I thankful for the info found here on this excellent forum. Bailed out once again by the FJR collective, especially Radman in this case. Without the confidence I've gathered from here I would have given up sooner been all bummed out wondering what to do next.

Happy Groundhog Day!

 
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