charcoal canister bypass shortcut

[alan hodge]

howdy....regarding charcoal canister bypass could you not leave canister/piping/purge valve in place and simply undo the tubes that go to intake manifold and then plug tubes?

 

[Alan F.]

I haven't dabbled with that personally but what you're saying makes sense.

I suppose some also remove that stuff to simplify and save weight.

 

[BernieBee]

Why do this? I'm just curious.

 

[alan hodge]

bike starts instantly when cold when hot still takes several pushes of button to make it go read this can be caused by canister soggy bike is new to me 8k miles maybe i should consider its hot start as normal to this machine and live with it bike perfect in all other categories as i said RE new to me am used to vintage BSA Triumph Norton and amal carbs

 

[Alan F.]

Ohhhh. My Interceptor takes a few pushes to start cold just as you said.
Food for thought.

 

[alan hodge]

opposite for me mine start great cold 1 push 3-4 pushes hot new CR8EIX plugs K&N filter TEC 2 into 1

 

[NVDucati]

Why do this? I'm just curious.

Curiosity is good.
The evap system is made up of two separate parts. The charcoal canister which, yes, has charcoal beads inside, and the "re-circ" valve along with associated plumbing.
The charcoal beads absorb odor. It does not absorb / contain or kill off hydrocarbons. The re-circ system has an electric valve which opens on a specified occasion to suck residual fumes from the canister housing into the intake manifold.

We have these evap systems, from a practical perspective, to stop or reduce the number of calls to fire departments. With the switch to fuel injected engines in cars, multi level indoor parking structures were persistently smelling of gasoline. That was alarming for the citizenry and expensive for the municipalities. You can find the various DOT committee minutes and the equivalent for other countries.
That is, obviously, a simplified explanation to save time. However, the race was on and it did, in fact, work to save all the false alarms and the yuckky smell.
For whatever tiny fractional content of hydrocarbons that exist in the fumes of gasoline ... the recic-valve does it's job.
_ Your question was ~ so why bother to remove the charcoal canister?
Charcoal canisters eventually fail. It is a slow process and the symptoms in turn develop slowly. Hard starting, lethargic running and eventually won't run at all. The problem is common to all systems but more so to motorcycles because of size limitations of both the canister and the fuel tanks. We tend to cram as much fuel as possible into the tanks and then it sloshes into the overflow / breather. The charcoal eventually gets saturated and closes off the air returning to the fuel tank.
_ What people decide to do is a personal choice. The canisters are fairly heavy and do get heavier as time goes by and gasoline collects. They are a bit of a hassle to change. If you live or work whereby your bike is parked inside then yes, you are sorta obligated to replace it when those vague symptoms start to show up.
Or if you are down there to replace a Rectify/Regulate... then you can consider heading off the inevitable.

 

[Woodstock]

Curiosity is good.
The evap system is made up of two separate parts. The charcoal canister which, yes, has charcoal beads inside, and the "re-circ" valve along with associated plumbing.
The charcoal beads absorb odor. It does not absorb / contain or kill off hydrocarbons. The re-circ system has an electric valve which opens on a specified occasion to suck residual fumes from the canister housing into the intake manifold.

We have these evap systems, from a practical perspective, to stop or reduce the number of calls to fire departments. With the switch to fuel injected engines in cars, multi level indoor parking structures were persistently smelling of gasoline. That was alarming for the citizenry and expensive for the municipalities. You can find the various DOT committee minutes and the equivalent for other countries.
That is, obviously, a simplified explanation to save time. However, the race was on and it did, in fact, work to save all the false alarms and the yuckky smell.
For whatever tiny fractional content of hydrocarbons that exist in the fumes of gasoline ... the recic-valve does it's job.
_ Your question was ~ so why bother to remove the charcoal canister?
Charcoal canisters eventually fail. It is a slow process and the symptoms in turn develop slowly. Hard starting, lethargic running and eventually won't run at all. The problem is common to all systems but more so to motorcycles because of size limitations of both the canister and the fuel tanks. We tend to cram as much fuel as possible into the tanks and then it sloshes into the overflow / breather. The charcoal eventually gets saturated and closes off the air returning to the fuel tank.
_ What people decide to do is a personal choice. The canisters are fairly heavy and do get heavier as time goes by and gasoline collects. They are a bit of a hassle to change. If you live or work whereby your bike is parked inside then yes, you are sorta obligated to replace it when those vague symptoms start to show up.
Or if you are down there to replace a Rectify/Regulate... then you can consider heading off the inevitable.

Thanks for a thorough write-up. My observation is that the cough several seconds after I turn of the 22 Interceptor is getting louder. If it is the evap system, and I have my suspicions, it is happening as you describe even as my dealership says they all do it. I am one of those who religiously fills the tank, while the bike is on the center stand, to within a millimetre of the splash guard. I'll worry about it when the time comes. I hate it when my chainsaws randomly give off the gasoline smell in the garage and I have to vent for as long as it takes. My furnace is also in the garage.

 

[BernieBee]

opposite for me mine start great cold 1 push 3-4 pushes hot new CR8EIX plugs K&N filter TEC 2 into 1

Ok, entering troubleshooting mode: Beep beep da beep!
The EVAP system feeds fuel vapours from the canister to the purge valve via a rubber tube. Out of the purge valve comes a second rubber tube which goes to a tee. Then the two tubes out of the tee go to the left and right sides of the throttle body. So. If you suspect that the EVAP system is causing hot starting difficulties, clamp the single rubber tube shut, either before or after the purge valve. If hot starting is still difficult, it's not the EVAP systems fault. Let us know!

 

[alan hodge]

good idea will do wait....plug line then ride? or wait til bike sits a few minutes and clamp shut and try / will riding plugged affect anything?

 

[USADoug]

We tend to cram as much fuel as possible into the tanks and then it sloshes into the overflow / breather. The charcoal eventually gets saturated ...

Yes. This is the root cause of EVAP canisters becoming exposed to liquid gasoline instead of just gasoline vapors. The best fix is "don't do that" as per the Owner's Manual.

If for some odd reason my canister charcoal becomes ruined I intend to cut open the bottom of the canister and discard the old charcoal. New suitable activated charcoal is dirt cheap on Ebay. I will repack with new and glue the canister bottom back on. Done and good as new.

 

[Eatmore Mudd]

Curiosity is good.
The evap system is made up of two separate parts. The charcoal canister which, yes, has charcoal beads inside, and the "re-circ" valve along with associated plumbing.
The charcoal beads absorb odor. It does not absorb / contain or kill off hydrocarbons. The re-circ system has an electric valve which opens on a specified occasion to suck residual fumes from the canister housing into the intake manifold.

We have these evap systems, from a practical perspective, to stop or reduce the number of calls to fire departments. With the switch to fuel injected engines in cars, multi level indoor parking structures were persistently smelling of gasoline. That was alarming for the citizenry and expensive for the municipalities. You can find the various DOT committee minutes and the equivalent for other countries.
That is, obviously, a simplified explanation to save time. However, the race was on and it did, in fact, work to save all the false alarms and the yuckky smell.
For whatever tiny fractional content of hydrocarbons that exist in the fumes of gasoline ... the recic-valve does it's job.
_ Your question was ~ so why bother to remove the charcoal canister?
Charcoal canisters eventually fail. It is a slow process and the symptoms in turn develop slowly. Hard starting, lethargic running and eventually won't run at all. The problem is common to all systems but more so to motorcycles because of size limitations of both the canister and the fuel tanks. We tend to cram as much fuel as possible into the tanks and then it sloshes into the overflow / breather. The charcoal eventually gets saturated and closes off the air returning to the fuel tank.
_ What people decide to do is a personal choice. The canisters are fairly heavy and do get heavier as time goes by and gasoline collects. They are a bit of a hassle to change. If you live or work whereby your bike is parked inside then yes, you are sorta obligated to replace it when those vague symptoms start to show up.
Or if you are down there to replace a Rectify/Regulate... then you can consider heading off the inevitable.

In the USA EVAP systems were phased in on passenger vehicles by 1973. The purpose was to capture hydrocarbons.
I forget what the last year of carberators was, sometime in the 1980's

 

[BernieBee]

good idea will do wait....plug line then ride? or wait til bike sits a few minutes and clamp shut and try / will riding plugged affect anything?

Ride until the engine is warmed up. Shut off engine. Plug the line. Attempt to start. If it now starts easily, the hard hot starts issue is probably caused by the purge valve being stuck open.

If you leave the line plugged for a short while I don't think much will happen. The cannister will get saturated and at that point it won't absorb any more fuel vapors. But don't plug the line as a permanent solution, because eventually fuel vapors will condense into liquid fuel in the cannister.

It sucks that the RE650 manual doesn't describe under what conditions the ECM signals the purge valve to open. But typically the engine has to be at operating temp and above idle speed and requires that the vehicle is traveling above a certain speed for the purge valve to open.

 

[BernieBee]

Yes. This is the root cause of EVAP canisters becoming exposed to liquid gasoline instead of just gasoline vapors. The best fix is "don't do that" as per the Owner's Manual.

If for some odd reason my canister charcoal becomes ruined I intend to cut open the bottom of the canister and discard the old charcoal. New suitable activated charcoal is dirt cheap on Ebay. I will repack with new and glue the canister bottom back on. Done and good as new.

This was my first modern bike and I'm glad I read the owner's manual! It states not to fill the tank above the bottom edge of the metal tube ("anti splash plate") that extends downwards from the filler opening. And when does a buyer read the manual? After filling the tank on the way home with their new bike! Royal Enfield would be doing customers a big favor by putting a temporary sticker next to the tank filler cap with that warning.

That cannister fix is a great idea!

 

[USADoug]

And when does a buyer read the manual?

This one does. But I will admit to already being aware of the common ruining of charcoal canisters in cars/trucks by forced overfilling (my career was in powertrain engineering at Chrysler). It's harder to do in cars/trucks now because of the forced shut-off of the fill pump with back pressure ( IF one is very persistent an overfill can still be achieved). There just isn't enough room in a motorcycle fuel tank to do the same.

 

[NVDucati]

This one does. But I will admit to already being aware of the common ruining of charcoal canisters in cars/trucks by forced overfilling (my career was in powertrain engineering at Chrysler). It's harder to do in cars/trucks now because of the forced shut-off of the fill pump with back pressure ( IF one is very persistent an overfill can still be achieved). There just isn't enough room in a motorcycle fuel tank to do the same.

Right on. Also the distance between the gas pump nozzle and the tank itself gives the car / truck an exponentially greater margin of safety compared to our motorcycles.

 

[Woodstock]

Yes. This is the root cause of EVAP canisters becoming exposed to liquid gasoline instead of just gasoline vapors. The best fix is "don't do that" as per the Owner's Manual.

If for some odd reason my canister charcoal becomes ruined I intend to cut open the bottom of the canister and discard the old charcoal. New suitable activated charcoal is dirt cheap on Ebay. I will repack with new and glue the canister bottom back on. Done and good as new.

You may also get lucky with a used one. One arrived one day in an order from a breakers and though it may or may not be good, there is no smell to it and it does not feel heavy as I would expect if it was ruined. The supposed mileage on the bike was fairly low I seem to recall. I just checked and there are a couple being sold on eBay. They may not be much new? An aside, but when I was investigating my Interceptor's post running cough, the purge valve itself is a common Bosch auto part with the Bosch part number rather than buying it as an Enfield part.

 

[alan hodge]

what think of this?

 

[NVDucati]

what think of this?

That is a very good video and easy to follow. The failure of is a matter of when, not if. They have a shelf life. They will last a very long time if one follows the best practices of refueling. However, if you are days away from home and the bike gets tipped over ... Everyone gets to decide their own plan.
_ I would make one comment about the video. Because he has been doing this for many years and many bikes, he may have simply overlooked telling us to make certain that the extended vent tube does not get pinched shut by the center stand when it is up. You can find some horrifying photos of tanks crushed by the vacuum created in a un-vented motorcycle tank.

 

[alan hodge]

i followed the instructions on the video and performed the procedure the canister felt heavy when i took it off and raw gas came out when i tapped it on workbench engine started right up and i let it warm for 5 minutes and started and stopped it several times it seemed to start better hot than it did before