A hot cold start

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mcatrophy

Privileged to ride a 2018 FJR1300AS
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Went to sister-in-law's for lunch today (very nice, but not the point).

I left the bike in front of the house on the drive, and in the sunshine (we've been having some unusually very hot weather for the UK), and joined the family at the back of the house in the shade.

Some five hours later, I get myself ready to leave, sit on the bike, start it, and was a little surprised to see the ambient temperature display showing 40C (104F), and the LCD screen was just beginning to blacken. But it had been sitting in the sun, so understandable.

Paddled the bike back to the road, selected first, started to open the throttle. As the clutch started to engage (this is a YCC-S bike), the engine misfired a bit, and as the clutch fully engaged, the engine stalled. Nearly dropped it because the bike was leaned over a bit. Stalling almost never, ever, happens on a YCC-S bike.

Pressed the starter, engine missed as it fired, I gave it a bit of throttle which got it running, then repeated first gear, throttle up, misfire and stall (only this time the bike was pointing straight ahead, I'm not completely stupid).

Thoughts started going through my mind, feels like the engine is lacking fuel, late Saturday afternoon, miles from home ...

Anyway, after the 4th or 5th attempt, it didn't stall, I could start to accelerate into 2nd gear, and it began to run normally.

So over the course of my trip back home I think I worked out what had happened. The bike had soaked up to a high temperature. The engine management computer probably thought the engine was already hot, so it ignored the cold start cycle, meaning that the engine wouldn't run properly. In retrospect, I remembered that when I started it, it didn't run at its cold idle speed, just at normal warm speed.

Not heard of an FJR doing this before, so thought I'd post it up.

Hoping it starts normally on the next cold start ...

 
How much fuel did you have? Sometimes when a full tank gets really hot, the fuel expands and does weird stuff. Was mostly seen in bikes with the charcoal canisters.

Or, maybe your cold-idle didn't kick in. Lol.

 
How much fuel did you have? Sometimes when a full tank gets really hot, the fuel expands and does weird stuff. Was mostly seen in bikes with the charcoal canisters.Or, maybe your cold-idle didn't kick in. Lol.
Fuel: I'd done about 30 miles since filling (and a normal fill, not right up to the gunnels). Charcoal canister: I have a sneaking suspicion I may have one of those, there's something screwed to the inside of the fairings, behind that trianglular panel, not seen one of these on any previous bike.

 
Charcoal canister like the California bikes would be the answer, if it has one. After a good heat soak, the fuel vapourized from the tank pretty much saturates the charcoal. When you start the bike, you are drawing fresh air over the canister contents making for an extremely rich mixture - way beyond what the ECU can manage. After 5 minutes or so, the worst of it is off and the bike will run as it should.

Despite the fact that I bought my '07 from a gentleman on the US east coast, it was a California model. After the first couple of times it gave me grief, I ended out bypassing the charcoal canister. Not a frequent issue in the Canadian Maritimes but any is too many.

Is there an additional small diameter hose exiting from the bottom of the front fairing? Also one (I think) extra screw at the bottom front that hold the canister bracket? (Attached to the side fairings, not attached to the triangle but sits just behind it.) At least on the Gen II.

So what's worse? The volatile hydrocarbons making it into the air we breathe - now trapped in the canister to be burned when you go again? Or the emission of aldehydes, organic acids, ketones and other partially oxidized and chemically reactive organic materials plus a large surplus of carbon monoxide from excessively rich running?

Not to mention the potential huge safety issue of your normally reliable motorcycle having a shit in the middle of the road (at the worst possible moment)!

 
Charcoal canister like the California bikes would be the answer, if it has one. After a good heat soak, the fuel vapourized from the tank pretty much saturates the charcoal. When you start the bike, you are drawing fresh air over the canister contents making for an extremely rich mixture - way beyond what the ECU can manage. After 5 minutes or so, the worst of it is off and the bike will run as it should.
Despite the fact that I bought my '07 from a gentleman on the US east coast, it was a California model. After the first couple of times it gave me grief, I ended out bypassing the charcoal canister. Not a frequent issue in the Canadian Maritimes but any is too many.

Is there an additional small diameter hose exiting from the bottom of the front fairing? Also one (I think) extra screw at the bottom front that hold the canister bracket? (Attached to the side fairings, not attached to the triangle but sits just behind it.) At least on the Gen II.

...
While I can't definitively rule out the cause being a carbon canister, I don't think it was. Once started, the initial tickover speed was consistently at the normal hot 1100 to 1200 rpm, not seeming to try for the cold 1500-odd rpm that I would expect if the ECU was attempting a cold tickover (remember the Gen 3 uses the ECU to control the throttle to achieve tickover, there's no throttle stop adjustment nor cold start mechanism like the previous Gens have).
Also, the misfiring and stalling felt more like fuel starvation/weak mixture, rather than an overly rich mixture. I'm old enough to have driven cars and a motorcycle with a manual choke (and had a motorcycle that needed its carburettor tickled when the engine was cold), so I know what it feels like when I forgot to operate the choke (or tickle the carb, though that bike was unlikely to start without!).

But I don't know for sure, and I'd not considered a "canister effect".

 
The picture is from the Yamaha UK site. The 2018 model is shown side view. I have circled the additional hose at the bottom which is (at least on Gen II CA model) a drain for the charcoal canister. Non-CA bikes don't have this hose. Also, check where the fairings come together at the bottom. Non CA bike has one bolt whereas the CA bike has one in the middle right at the front and one on each side an inch or so back to hold the canister bracket. With a flooded (saturated) canister, the bike runs horribly!

2018-yamaha-fjr1300as-eu-phantom-blue-studio-002.jpg


 
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I'm beginning to succumb to the carbon canister theory.

Had a crawl on the garage floor this morning. Saw the two "extra" screws, and a hole in the bottom of the fairing. After a bit of a finger-prod and poke, I found the rubber breather pipe that should go through that hole, scrunched up in the fairing, very possibly folded sufficiently to block it.

Managed to un-scrunch the pipe and get it through the hole.

What would happen if that breather was effectively blocked? Does it breath in or out?

Took a couple of pics after I'd got the breather back through its hole, the first taken using a mirror on the floor, the second a side-on view showing the breather sticking down.

(Click on image for larger view)


Guess our emission regulations are getting more severe.

(Someone's bike needs a good clean. Far too sunny and hot at the moment. At least, that's my excuse.)

 
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If you look at an on-line parts fiche (under Fuel Tank) for the UK 2018 model, you will see the canister assembly as part #47. Definitely present!

Now, if you look at a North American parts fiche, you will see where the differences between the California and non-California models lie:

https://www.partzilla.com/catalog/yamaha/motorcycle/2016/fjr1300a-fjr13agc/fuel-tank

That's a 2016 but I think the same as 2018 for that stuff.

If you choose to "fix" yours, it shouldn't be too difficult once you see how they are put together. (Use the NA fiche)

Snip from UK Fiche:

Canister.jpg


 
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My brother's GS had one. Only experience I have ever experienced with a charcoal canister, other than the discussions here. Every time we would stop, get fuel, and then eat, his bike was FUBAR. He thought something was seriously wrong. FJRForum came to the rescue again, because I figured out what it was. We just stopped filling before we ate and it cured the issue. When we hot home, Patch pulled that POS off his bike, and never had another issue.

Mac, just make sure you plug the tubes. At least one of them is a vacuum and will draw dirt into your head if it's not sealed up.

 
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