Fuel injection/throttle issues in hot weather

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Krob

Member
Joined
Aug 8, 2010
Messages
7
Reaction score
0
Location
San Diego, CA, USA
I've recently moved back to Tucson with my 2010 FJR. Twice now, when I've come to the bike after lunch or an off-site visit, I've had issues getting power/acceleration out of the bike. Both times the bike made it to where I was going just fine, but after sitting in the sun for 30-45 minutes I've had it run extremely rough. In both cases the thermometer read 110+ at startup.

I don't recall the specifics of last summer's incident, but today I went out to lunch then visited an customer with out any abnormal behavior. When I went to leave the customer's site, however, the bike wouldn't turn over. Started spun up, but there was no firing. Cycling the ignition, I didn't hear the fuel pump prime, but it might have been muffled by my helmet, the wind, and old ears. After several attempts with various levels of throttle it finally sputtered once and then started an attempt or two later. Once running, my experience was pretty much what I remembered from last summer, giving it a little gas and letting out the clutch felt like the bike was going to stall (it did actually stall last summer). Only way to get the bike moving reliably is to lay into the throttle and ease out the clutch from a high rev. As we're moving in to warmer weather and I'm going to be riding my bike a lot more than I did last summer, I need to get this figured out and fixed.

Has anyone seen this before or have any suggestions that can be easily tried or brought to my mechanic? I haven't found any postings here or elsewhere with this exact problem and a solution. Common theme for starting problems in hot weather is to replace the battery (did that already) and adjust the CO mixtures which seems to be a bit more involved than I'm comfortable with, even so didn't find any that came back saying this fixed it either.

Cheers,

Nate

 
Your problem is that you have a California Spec bike!

When the ambient temperature gets hot, vaporized fuel from your tank makes its way to the charcoal canister at the front of the bike. It gets pretty much saturated after a time. When you go to start the bike, the fuel injectors supply the normal amount of fuel BUT air is also being drawn through that fuel-saturated canister making the bike run stinking rich until most of the excess fuel in the charcoal has evaporated off and been burned in the engine. It can take several minutes before the bike runs right.

Your choice is to put up with it or do some creative plumbing to eliminate the charcoal canister altogether. Remember to block off the line going to the airbox or unfiltered air could make its way to your engine. Despite the fact that my bike was purchased on the East Coast, it was a Cali bike and I had this issue on very warm days until I "fixed" it.

Too bad everything wasn't this easy - at least I hope that is your issue!!

 
Last edited by a moderator:
A mate here in Sunny Queensland had a similar problem.

He bought the bike here only for me to find out it was a CA, California bike imported into Australia.

Turns out it was another mates bike that he imported when he moved over here, lol lol. Small world.

The bike had venting problems as well as a stuck fuel tip over valve, I just removed all the CA spec stuff and never a problem.

 
Just like the good old days, almost. Carburetor cars on very hot days, FUEL would boil inside. Flooded. THEN no liquid fuel could get there still too hot.

Fuel injection is better 45-55 PSI raises boiling point because of pressure.

Canister is purging at start up, too rich mixture. Flooded.

Plug vacuum line to canister at throttle body or remove parts and modify to non CALF. spec

 
Thanks for the quick replies all. That seems like a consensus and searching on the CA charcoal canister seems to provide further evidence. Effin' CA. :p

Cheers,

Nate

 
Interesting... my '05 (yes, a CA bike) just did something similar. We're getting a little break from the rain and temps have been in the 70's this week. Went to leave work earlier this week and bike took more than normal cranking to fire. Regular high-idle but it was stumbling and blubbering at low revs upon trying to leave. Not wanting to get out into traffic like that, I did a few laps around the building and it improved enough to head home and then cleared up within a few miles. The rest of the week it ran normal with no issues. A few things to note: I had a full tank of fuel and bike had been sitting in direct sunlight few hours. In addition, I changed buildings back in Dec. and previously had a nice shady spot to park, even on the hottest days; not so with my current spot. My first thought was that I had gotten perhaps a slug of water in the tank from some of the recent rain but after reading this thread, I think the CA emissions gear is likely the culprit! Thanks!

Regards,

Mr. BR

 
Charcoal canister. Eventually it will turn to pudding and your bike will suck black epoxy and weld your junk shut. Did on my BMW anyway. I didn't look into canisterectomy until too late. Cost me over $500.00 to fix the problems it caused.

 
If you would be so kind, please add a note of what step you take that fixes the problem. Far, far too many searches end up identifying individuals with similar problems, but not too many solutions...

 
Have a look at the parts fiche for California and non-California bikes and you should be able to figure it out. I unhooked my canister and blocked lines. If you remove it, you will shed a couple of pounds but you have to do something with the way the two fairing halves join. (they attach via the canister bracket if I remember correctly - Cali fairing is slightly different.

 
Have a look at the parts fiche for California and non-California bikes and you should be able to figure it out. I unhooked my canister and blocked lines. If you remove it, you will shed a couple of pounds but you have to do something with the way the two fairing halves join. (they attach via the canister bracket if I remember correctly - Cali fairing is slightly different.
I would not stop at just removing the charcoal canister, rip out the whole PAIR system, it's useless crap.

A forum member (08FJR4ME) from WYNPRO makes very nice block off plates for a nice and uncluttered look and access to your engine or you can leave the existing covers and just block off the holes.

https://www.fjrforum.com/forum/index.php?showtopic=117074

https://www.fjrforum.com/forum//index.php?showtopic=117073

https://www.fjrforum.com/forum//index.php/topic/116612-wynpro-air-induction-cover-plates/

100_4475_zps9f59977a.jpg


 
Last edited by a moderator:
If mine wasn't under warranty, I'd have wynlro plates on it. For canisterectomy, (not on an fjr but in a very similar cali compliant system), I pulled the can off, plugged the tube that had run to it with the screw that had formerly secured the can to the bike, and had no further problems. But that was after extensive exploration and replacement of the fuel filter and fuel pump, at considerable expense.

 
Last edited by a moderator:
Have a look at the parts fiche for California and non-California bikes and you should be able to figure it out. I unhooked my canister and blocked lines. If you remove it, you will shed a couple of pounds but you have to do something with the way the two fairing halves join. (they attach via the canister bracket if I remember correctly - Cali fairing is slightly different.
I would not stop at just removing the charcoal canister, rip out the whole PAIR system, it's useless crap.A forum member (08FJR4ME) from WYNPRO makes very nice block off plates for a nice and uncluttered look and access to your engine or you can leave the existing covers and just block off the holes.
I agree 100% about the PAIR system. It creates a mess under the tank and while I haven't heard of running problems associated with it, I don't think there is any downside (except to the environment) for removing it. The block off plates from WYNPRO that JamesK mentions are very nice. (I removed my PAIR system as well.)

The PAIR system does not, however, connect with the California vapour collection stuff. (Just another device to help save us from environmental destruction.) The Kalifornia Krap operates passively to absorb evaporating fuel from the tank, while the bike is sitting, before it makes it to the atmosphere. Unfortunately, when this fuel is fed back into the engine after startup (air routed through canister to intake), the engine runs so rich that the levels of CO, unburned hydrocarbons, and partly combusted hydrocarbons is probably at least as bad (environmentally) as the raw fuel vapour would have been. Not to mention the safety aspects of trying to ride a motorcycle that does not respond properly to the throttle.

Note: This is not a big problem most days (at least where I live) but if the bike is sitting in the sun with high ambient temperatures, you are going to have issues.

 
Last edited by a moderator:
Top