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I have 2020 Ultra, CA emissions. The EVAP system is similar to our cars and trucks from what I understand, it's a closed system. The gas VOCs are captured in the charcoal canister. Recently, it's started to fill my garage with fumes - bad. This is not normal because A) it's a closed system, but most importantly B) this just started, it didn't do it the 4 years prior.
Anyone else with CA Touring bike that has had anything similar? I'll replace the gas cap this weekend. I've inspected the EVAP system as much as I could without tearing into it. I pulled the dash panel on the tank, all ok. There is no liquid gas leak.
Any input would be appreciated. Thanks.
Last edited by Jack Straw; May 13, 2025 at 02:43 PM.
1. I would check all your line connections from the gas tank to the carbon canister to ensure none were disconnected.
2. Check you solenoid purge valve #5 and make sure the electrical connections are good and do not have corrosion.
3. If all the above is good, you may need a new carbon canister #7 if it is saturated.
4. Check your fuel line connection on the gas tank and make sure it is seated correctly, my not leak enough gas to be visible but enough to smell.
Make sure your gas cap is closed. I had a gas smell once but it just needed to be re-closed. You could have a bad gasket or knick/deformation in the opposing metal parts.
1. I would check all your line connections from the gas tank to the carbon canister to ensure none were disconnected.
2. Check you solenoid purge valve #5 and make sure the electrical connections are good and do not have corrosion.
3. If all the above is good, you may need a new carbon canister #7 if it is saturated.
4. Check your fuel line connection on the gas tank and make sure it is seated correctly, my not leak enough gas to be visible but enough to smell.
I've owned 2 CA Twin Cam bikes and currently still have one. It's an '03 I bought new, and has never smelled up my little garage/shop with fumes. I've filled it, and driven a couple miles home and parked it... no smells.
I have 3 Twin Cams I bought used and are not CA bikes. If I fill them before parking them, and don't drive at least 8-10 miles before parking, they will fill my little garage/shop with gas fumes in short order.
I suspect something in your venting side (shown in the above parts pic) is loose, broken, or disconnected.
FWIW...
The vent system is a one-way, directional system. The gas cap is a vacuum vented cap. It lets air into the tank, as fuel is used, to avoid building a vacuum in the tank. Then the vent through the tank plate, relieves positive pressure from the tank. It is the only way fumes (pressure) can escape the tank. The fumes are directed to the canister and/or back to the intake, via the purge valve solenoid. If the tank cap vented both ways, the canister system wouldn't work.. All fumes would take the path of least resistance and go in & out the cap.
A failed gas cap will usually allow vacuum to build... I guess it could be damaged and allow fumes to escape. However, I have never taken one apart to see just how it works, or if it failing open is even possible.
Last edited by hattitude; May 13, 2025 at 07:50 PM.
I've owned 2 CA Twin Cam bikes and currently still have one. It's an '03 I bought new, and has never smelled up my little garage/shop with fumes. I've filled it, and driven a couple miles home and parked it... no smells.
I have 3 Twin Cams I bought used and are not CA bikes. If I fill them before parking them, and don't drive at least 8-10 miles before parking, they will fill my little garage/shop with gas fumes in short order.
I suspect something in your venting side (shown in the above parts pic) is loose, broken, or disconnected.
FWIW...
The vent system is a one-way, directional system. The gas cap is a vacuum vented cap. It lets air into the tank, as fuel is used, to avoid building a vacuum in the tank. Then the vent through the tank plate, relieves positive pressure from the tank. It is the only way fumes (pressure) can escape the tank. The fumes are directed to the canister and/or back to the intake, via the purge valve solenoid. If the tank cap vented both ways, the canister system wouldn't work.. All fumes would take the path of least resistance and go in & out the cap.
A failed gas cap will usually allow vacuum to build... I guess it could be damaged and allow fumes to escape. However, I have never taken one apart to see just how it works, or if it failing open is even possible.
1. I would check all your line connections from the gas tank to the carbon canister to ensure none were disconnected.
2. Check you solenoid purge valve #5 and make sure the electrical connections are good and do not have corrosion.
3. If all the above is good, you may need a new carbon canister #7 if it is saturated.
4. Check your fuel line connection on the gas tank and make sure it is seated correctly, my not leak enough gas to be visible but enough to smell.
You're spot on. I did check all connections at the purge valve, including electrical. I didn't dig into the canister, looks like I'll need to remove the battery. I carefully checked the fuel lines, running and after I shut the motor off.
The smell accumulates after it sits a while. Again, it's bad. I'm almost sure you're correct, its the canister and/or it's connections.
If I'm lucky, it's the fuel cap. The canister is in front of the battery box, correct? Thanks again, it's very much appreciated.
Last edited by Jack Straw; May 13, 2025 at 09:51 PM.
Make sure your gas cap is closed. I had a gas smell once but it just needed to be re-closed. You could have a bad gasket or knick/deformation in the opposing metal parts.
For the past four years, have you parked the bike with a partial load of fuel, but NOW you park it just after refueling? My bike is not a Ca spec bike. Unless I put a block of wood under the side stand, it will barf fuel out the over flow when I park it just after fueling.
For the past four years, have you parked the bike with a partial load of fuel, but NOW you park it just after refueling? My bike is not a Ca spec bike. Unless I put a block of wood under the side stand, it will barf fuel out the over flow when I park it just after fueling.
I have an '01 Springer that's not a CA bike. I've had that happen a few times. Seems to happen more the hottter the engine and the hotter the ambient temp...
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CA emissions bike - extreme gas smell
