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Evap removal from V7III

Just purchased the ECU unit, and am currently trying to figure out what all I am removing according to aforementioned information/diagrams (thank you all for what you have already provided). To be clear, I think the cable I need to remove is shoved up underneath the gas tank (circled in yellow), and the UNIT itself is behind the oil pan?

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Just purchased the ECU unit, and am currently trying to figure out what all I am removing according to aforementioned information/diagrams (thank you all for what you have already provided). To be clear, I think the cable I need to remove is shoved up underneath the gas tank (circled in yellow), and the UNIT itself is behind the oil pan?

View attachment 20106 View attachment 20107

Just did this myself and had a lot of hesitation. If you’re anything like me, it may be helpful for you to work backwards. Reach under the bike, and give a little tug on the hoses connected to the canister. Doing that while watching for the motion of the hoses further up helped me to trace the lines back up and confirm what’s what.
 
Thanks for posting this procedure with pictures. I bought a used 2017 V7iii last summer. I've noticed some tank suck when taking the gas cap off and it seems to struggle a little to find its idle when I first start the bike (and sometimes when the bike is hot.) The idle is now about 50RPMS lower than it had been. Do you think removing the EVAP will help with this? I'm thinking about trying it but I'm a little worried about screwing something up. Do I plug the tank breather hose after cutting it? I thought I needed that line to be open in order for the tank to breath? That's the only part that's throwing me. How's your bike holding up 2 year later?

EDIT: I've done some more reading on this procedure since I posted my question and everything seems to make sense now. As far as the breather hose, would it work if I just remove the clamps that hold the check valve in place on then stick a small fuel filter or something that connects the two halves and lets air flow through... leaving the other end attached to the EVAP canister? Hope that question makes sense. It seems like the evap can would catch any gas that might splash into the hose and reduce fumes if I leave it attached and just replace that check valve thing with some sort of hose connector. Thanks!
 
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Just removed the evap line. Below some pictures. I removed the breather valve, replaced it with a fitter 1/4 to 3/16 and left the tank line plugged into the canister so the carbon compound will absorb fumes odor. Then I unplugged the intake line from both sides: canister and manifold intake and plugged the hose on both sides with 2 small caps so the hose remains in place but completely disconnected. Ultimately, installed a vacuum cap on the intake manifold with a clamp. A 1/4 vacuum cap works just fine but I preferred a 3/16 so it goes more snug.

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Thanks for posting those pictures, I'm getting ready to disconnect my evap canister. What did you use to connect the breather hose parts after removing that check-valve thing? And what's the easiest way to get those clamps off? I'm going to do the same thing and leave the breather hose connected to the canister. I'll remove the check valve and replace it with some other connector that allows air to flow. Also, why did you use a 1/4 to 3/16 connector, are the hoses on either side of the aray and green check valve different sizes? Thanks.
 
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EDIT: I've done some more reading on this procedure since I posted my question and everything seems to make sense now. As far as the breather hose, would it work if I just remove the clamps that hold the check valve in place on then stick a small fuel filter or something that connects the two halves and lets air flow through... leaving the other end attached to the EVAP canister? Hope that question makes sense. It seems like the evap can would catch any gas that might splash into the hose and reduce fumes if I leave it attached and just replace that check valve thing with some sort of hose connector. Thanks!

Also, why did you use a 1/4 to 3/16 connector, are the hoses on either side of the aray and green check valve different sizes?

The hose is a different size. You can get the 3/16" into the 1/4" hose with a little work(I used a dab of vacuum grease).

I originally turned my canister into a vent filter like you're describing. I eventually just got rid of it all and left a brass coupler on the vent hose. Tied it up so that if fuel does vent, it would dump on the ground mid bike. During operation I really don't see that as an issue since you should have negative pressure in the tank.

The canister can get in the way when I jack up the bike to work on (nose chock and hydraulic lift mid bike on the bar just behind the canister). Haven't had any leaks and I've found I only smell gas after a good ride, the bike is parked in the garage and the tank is full. Not a strong smell but you can smell it. With the canister on I still smelled fuel under the same conditions, maybe a little less. I'm of the opinion that a garage should have a smell of fuel present.

Like you, I had a lot of negative pressure in the tank. After I initially bypassed, Idle was smoother.
 
My perspective on the Evan can and SAS pump modifications are to know/have better control over what’s going into the intake track.
I am guessing that with the new tune in place, the maps that have been worked out *should* be working with fewer variations on what’s getting dumped into the manifold from those two things and be more in control on what’s happening based on the air / fuel that it manages going in and the readings it’s getting from the sensors on the way out...
 
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I have done both mods, but left the canister in place for vapors and drips. I'm considering methods to lose that worthless canister, and instead having that line end in some smaller trap that can naturally evaporate over time. I'm envisioning the line glued to the inside of something like a cigar holder, with felt at the top...
Hmm...
 
I have done both mods, but left the canister in place for vapors and drips. I'm considering methods to lose that worthless canister, and instead having that line end in some smaller trap that can naturally evaporate over time. I'm envisioning the line glued to the inside of something like a cigar holder, with felt at the top...
Hmm...
I used the canister as a filter for a while. Eventually removed completely and left the vent line pointed down with a brass nipple in the end. Have never seen any fuel vent. Have smelled vapor. Thats it. I park in a concrete garage attached to the house and any fuel spilled is very noticeable.
 
Todd's been stressing I should can the evap system and its 'vacuum leak' since I started talking to him about the ECU reflash for Racer. Well, this morning, my second test of the ECU map with a stone-cold start on a chilly morning proved conclusively that Todd's work on that is absolutely spot on: Start, fifteen seconds to get a little heat into the cylinders, ride away ... no stumbles, no lean spot, nada. Just perfect. Thanks Todd!

But, as I returned home a couple of hours later, I noticed that the idle revs were acting a little "funny" and that the throttle seemed a hair "sticky." No idea why, but killing the motor and restarting cured both symptoms. Two miles later as I pulled into my driveway, the sticky throttle sensation was back again.

On a hunch, I opened the tank and heard a gasp of air, there was a vacuum building up in the tank. Ah hah! the evap can and it's valve were screwing up as I was told.

I spent a bit of time with the V7III ABS Service Station Manual PDF and finally found the evap system on page 234-237 as "Sistema evaporativo canister". Now I could see where they were located approximately and understand the operation completely. Vacuum line connects to the evap can to draw fumes through the tank breather after passing them through the charcoal. The valve is supposed to limit how much vacuum is applied and vent when it's too much. Obviously, it wasn't working right. A cheap and crappy valve, essentially, is the cause of the problem. But the system is ugly anyway and almost totally unnecessary for the evaporative emissions of a motorcycle.

Not having much time, I pulled the seat, side cover, and starter cover. Yup, there are the lines from the intake manifold to the canister under the gearbox, there's the tank line with the valve in it. Looking at the flow from manifold to canister, it was obvious how to do the quick'n'dirty: I cut the line going to the manifold and stuffed a blanking plug into it to stop the vacuum leak. I then cut the line coming from the tank vent and going into the canister just above the valve gizmo, and cut the bottom line and the valve off the canister. No more vacuum leak, and the tank now vents to atmosphere exactly the same way my LeMan V tank did ... just a small line leading from the top of the tank down behind the starter.

Procedure:

- remove seat
- remove left side panel (three bolts)
- remove starter cover (two bolts)
- locate vacuum tap line from manifold to canister under the gearbox
- locate breather line with valve connected to canister
- cut vacuum line and block it (I glued an aluminum slug in place)
- cut breather line above the valve and below at the canister inlet
- leave the breather line open ended behind the started ... put a filter on it if you worry about environmental dust getting into the tank
- replace starter cover
- replace side cover
- replace seat​

You're done.

note: Another one of those cheap clip nuts broke when I removed the side cover. Glad I got six better quality spares! That's three now... I'm going to pick up another dozen because I see them all over the place on this bike.

I'll clean up my work next time I get a chance by removing the vacuum line and canister completely and using a good vacuum tap plug, maybe extend the breather line down an inch or two and put a little filter trap on it. But this will suffice for the present.

I'll see what its behavior is on my run out for dinner tonight.

BTW: Is this little valve on the breather line what's referred to as the "tip valve"? Or is that something else still? ... Thanks!

G
I know I'm years late to this conversation - and I apologize if this has already been answered, but I wasn't able to locate an answer to what I am looking for. Would replacing the faulty valve with one that actually works be worth the effort? I note in another post you mentioned spacing and sizing issues with the EVAP system and am wondering if that is the reason a valve replacement isn't suggested?

I would like to perform this at some point, but I'm only a few weeks away from the first service and would hate to have the dealer tell me these alterations caused my warranty to be voided.

I wonder if anyone has complained about this to the dealers and I'd be curious to hear how the dealers have responded...
 
Personally, I would wait until after the first service.
They don't need ANY more reasons to whine...

I couldn't wait and modded before my first service. I tried to be subtle, turned the can into a filter and put an inline plug on the leak side. Pretty much looked stock unless you dug into it. After my first service my dealer told me " Excellent modification!". Afterwards I just pulled it all out.
 
That’s the difference- some dealers are looking for any excuse to wash their hands of any warranty work.
Others are quite practical.
Yep - I'll gauge how they respond when mentioning this... I don't know how many dealers there are in the tri-state area, but based on the number of Guzzis they have at the garage at any given time, they get a lot of service work - therefore, they probably have a stock response ready when a rider brings up EVAP system issues.
 
When I had my first service done, when I went to pick it up, the mechanic said something like, "I see you EVAP system fell off. Funny, they do that frequently. Well, good riddance ... They do nothing but cause problems anyway." :D
I heard the same thing when I pickup mine up after it's first service. Almost the exact same wording.
 
Looking around under the bike today,
A question for anyone who removed the evap canister, did you do anything with the bracket?

It looks pretty heavy duty for holding a little can ?
Can you say overkill !
 
I have a 2019 V7 III Stone with 900 mile service just completed. Several times I've ridden from sea level to 6000ft and back during our 90-100 degree days. Fueling going up is fine but coming back down to about 2,000 feet I notice the engine isn't quite as smooth as usual. Throttle response is still good, especially since removing cable slack. And thanks to this thread I noticed the swoosh when removing the gas cap.

The story I've read so far was useful but seemed incomplete. When people take their cars to their local Autozone, et al for a CEL, the first question is: Did you fully tighten your gas cap? If Yes, the second question is: Is your car more than five years old? If Yes, they sell you a gas cap and the problem often goes away for another five years.

So I examined my gas cap and found this:
Gas Cap Valve
It's a unidirectional valve flowing outside air INTO the gas tank via the keyhole. I re-assembled it without the spring.

As I recall from disassembling the three-port canister on my Royal Enfield (to downsize, not remove it) it included a simple flap valve. As depicted on the emissions sticker, the MG canister is three-port and I suspect has an interior valve too (there is what looks like a fourth port but no connections are shown).
Emissions Label
The gas cap spring is the only change I'm making at this time. I'll report back in a few hundred miles.
 
The gas cap spring is the only change I'm making at this time.
Things like this are what this site was founded on. Thanks for posting. For the world markets that don’t have evaporative emission requirements, they vent through the gas cap like yesteryears. This is in essence what you’ve done.
The “pressure valve” Is the problematic part, and to those with sensitive nostrils, leaving the fumes to vent through the evap can (not under vacuum), is most ideal.
 
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