V7-850 Evap and Tip Info

[Tom Prescott]

Another question, does the ECU controlled Bosch valve open so the intake can then draw the fumes into the intake from the canister through that line and open valve for reburn? (my line is now plugged going to the intake) and if the top Bosch line is left open will gas vapors from the canister be release to atmosphere through it? (my top line is open). Ps I'm thinking of plugging the from the canister to the bottom of the Bosch valve as I get a little gas smell after a good ride. Thanks.
I'm trying not to think about it too much about it as it runs fine.

 

[GTM®]

does the ECU controlled Bosch valve open so the intake can then draw the fumes into the intake

Yes, but not “reburn” - it simply controls the intake vacuum so that it doesn’t constantly pull through the canister. Such an overly complex “solution.” Back in the day the gas cap simply vented to the atmosphere. Now the world is collapsing because of it. You can plug the line below too, just don’t cap the Bosch valve.

 

[GTM®]

This will be deleted, but I had a laugh of it…

Cattle are the No. 1 agricultural source of greenhouse gases worldwide. Ban the cows! NO WAIT… Termites are one of the top producers of methane in the animal kingdom. Cows rank far below them, believe it or not. BAN THE TERMITES!
That or they both need emission systems in place.

 

[Tom Prescott]

Yes, but not “reburn” - it simply controls the intake vacuum so that it doesn’t constantly pull through the canister. Such an overly complex “solution.” Back in the day the gas cap simply vented to the atmosphere. Now the world is collapsing because of it. You can plug the line below too, just don’t cap the Bosch valve.

Thanks Todd, does the ECU learn at all from such changes as this?
ps. My SAS kit arrives today. I'll post on that page.

 

[GTM®]

Thanks Todd, does the ECU learn at all from such changes as this?

GTM Fueling Info

A fact to start: No stock Guzzi ECU/F.I. system is fully adaptive, nor can 99% of the dealers do anything to help as they are mostly factory map/warranty restricted. If you modified your bike, it will NOT adapt. Even completely stock, fuel mapping is set up for emissions, not the health and...

www.guzzitech.com

 

[Frostbitten]

Humm, so I gutted the tip valve and reattached it. Then I pulled the hose that comes from the bosch valve off at the canister and plugged the hose, leaving the top of the canister open. I still have gas smells. Did I plug the wrong end?

 

[Akis]

My 2021 850 Special was experiencing the typical “cutout” issue we have all historically described. My Moto Guzzi dealer mechanic actually called last week and without saying the exact words, encouraged me to pursue the EVAP mod which he said came from their discussion with Italy. Finally had time to deal with mine today. I prefer to do mechanic’ing so things don’t appear like a hack job. So, for my mod, I drilled out the check valve then reinstalled. For the vacuum hose, I made a 5/16” diameter 3/8” long metal slug for a plug. Inserted the slug in the hose 1 inch above the Bosch vent valve, then reconnected that hose to vent valve and reinstalled the factory clamps. All this to say, my system "appears" stock, but functions per the modification. Lastly, as expected, it cured the engine “cutout” issue.

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Hi there.Intend to follow your way as much preferably system to appear stock since bike still under guarantee. Forgive my ignorance but for being on the safe side that i will do it on right way would you please clarify to me whether diameter 5/16” of the metal slug is the inner or the outer one?If the outer what should be the inner one?

Best regards

 

[zunak]

Thanks for all the information regarding this issue. I am going to pursue this using the initial post method. I would however like to keep it in a condition that is easily reversible. Is there any reason why the tank vent valve cant be removed completely and a connector inserted in its place rather than gutting or drilling out the valve?

 

[john zibell]

Thanks for all the information regarding this issue. I am going to pursue this using the initial post method. I would however like to keep it in a condition that is easily reversible. Is there any reason why the tank vent valve cant be removed completely and a connector inserted in its place rather than gutting or drilling out the valve?

You could do that. It was a common mod on Tonti bikes. But believe me, you do not want that tip over valve in the system.

 

[FedeleMotoGuzzi]

Great write up. Any concerns with the tank venting into the canister that now has no exit? Or is it fine if vapors and possibly raw fuel end up in the canister indefinitely? Or am I missing something?

I like the "stock" appearance you've tried to maintain, mostly because it seems like it prevents vapors escaping but still works per the mod. The reason for my concern is my bike is kept in a garage with a gas water heater. I would prefer the tank to not freely vent into the atmosphere.

Horribly late on responding...my apologies! Way too many projects and only surface when I have questions. I have ZERO fuel vapors from this mod.

 

[FedeleMotoGuzzi]

Thanks for all the information regarding this issue. I am going to pursue this using the initial post method. I would however like to keep it in a condition that is easily reversible. Is there any reason why the tank vent valve cant be removed completely and a connector inserted in its place rather than gutting or drilling out the valve?

No, there would be no reason. I kept mine (drilled out) to maintain the "appearance" of stock parts.

 

[FedeleMotoGuzzi]

For the record, this 850 Special is my "daily driver/run around with the guys on the back roads/curves" bike. I am up to approximately 7K miles and zero

I'm new to MG, my introduction being a 2021 V7 Stone, which I've been riding for 5 months. I love the bike but my enjoyment is marred by what feels like a sudden loss of fuelling at random moments, especially when doing a steady 30-40mph. It creates a momentary lurching forwards. Is this what is referred to in this thread as hiccuping or cutout? If so, should I consider the EVAP mod? I've discussed the issue with my dealer several times, but not got anywhere with that avenue so far.

Sorry for the VERY late reply. Difficult to say if your issue is the same, but sounds similar.

 

[FedeleMotoGuzzi]

Ty danketschpel. Your picture and explanation made it seem easy enough. Gave me the motvation to finaly do it after she hesitateted to start after a short stop on a group ride today. Looking forward to testing it tomorrow:

Most mechanic and electric items can be figured out in short order if you study them for a bit. Once a person understands how something is SUPPOSED to work, it becomes easier to troubleshoot or modify.

 

[FedeleMotoGuzzi]

I have a late 2022 V7 850 Special which currently dosnt seem to show any of these issues (I will add I havnt been riding in hotter temperatures yet), however Im keen to persue this mod and the method you detail seems almost the easiest , makes sense and leaves the system looking 'stock'. Couple of basic questions, some show the 'block' of the Bosch vent valve above the valve (as you do) and some below. Guessing it dosnt make any difference where the block is as the electrical connection to this valve dosnt care?
Secondly with your mod you have left the canister under the bike in place I assume? ( I have fitted a factory center stand and retained the canister currently)

Correct, I did NOT remove the canister.

 

[FedeleMotoGuzzi]

Hey,

So I’ve perused the thread and have a basic understanding of what to do, however I’m still a bit confused. I opened up the bike today and see where everything is, but when it comes to the 2 hoses, I’m confused on which to cut (both?) and which one I need to clamp or put something in.

So the right one is the Bosch one that needs to be kept closed somehow, and the left one I can just cut and zip tie to something else?

I figured to leave the canister in for now, just want to figure this part out first and then remove that after.

I am very new to all this, I don’t know what the manifold is (or where or anything at all). I’ve googled for a video but haven’t found anything that shows enough.

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Did you ever figure this out. The only item I don't see in your pic is the check valve on the bottom end. Maybe under the starter?

 

[FedeleMotoGuzzi]

Thanks for all the great info concerning this subject. So, you plug the line above the Bosch-valve and remove the internals of the tank vent line plastic valve, all clearly understood. But what about the connections of these two lines to the canister? Do they stay connected to the canister or do you leave them open?

I did nothing else but what is represented in the photos I posted. Very minimal and works.

 

[FedeleMotoGuzzi]

Good topic but as a non-native english speaker I read it ten times and still have to ask just to make it sure that I don`t destroy anything Sorry that I borrowed some pictures from this topic.

1. As shown in the picture; the hose from tank to evap-canister (marked as yellow/1.) could be replaced with a new straight hose and the end that was connected to evap-canister could be left to free air (as that is just a fuel tank breather if I understood correct) ? Other options are to open vent and remove insides or just to drill through ?

2. The second line (marked with blue/2.) is the hose with electronic vent. It should be plugged but connector should be left attached? Does it matter do I plug it from bottom or above the vent ? I would assume plugging it from bottom (between the evap canister and vent/red arrow) would prevent dirt from getting to vent and the hose from vent to intake could be left as is ?

If some professional could confirm these I promise to make clear point to point instructions with pictures about evap-delete so that even us non-native would understand

I will try to remove the canister too. I had no issues with fumes on my previous bike and it had just straight line for the fuel tank breather. There might have been some kind of "blowback-vent" (I don`t know what it`s called in english) to prevent flow to the otherway but it had no evap-system.

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Did you pursue this fix? Were you happy with the results?

 

[FedeleMotoGuzzi]

Hi there.Intend to follow your way as much preferably system to appear stock since bike still under guarantee. Forgive my ignorance but for being on the safe side that i will do it on right way would you please clarify to me whether diameter 5/16” of the metal slug is the inner or the outer one?If the outer what should be the inner one?

Best regards

OD of the plug

 

[anders]

Did you pursue this fix? Were you happy with the results?

Not yet. I will wait until driving season is over. Or if it keeps raining maybe I`ll do it some night.

 

[FedeleMotoGuzzi]

Since I'm not good about getting back on the forum unless I have questions or need some education that I cannot readily find, I'll add the following for my own fix. This 850 Special is my "daily driver/run around with the guys on the back roads/curves" bike. I have ridden this to approximately 7K miles since my "fix" and have had absolutely ZERO issues and the original problem went away immediately. As Todd mentioned a page or two back, there is a permanent fix for the issue we were experiencing "This is a small step to help with fueling. This; https://www.guzzitech.com/forums/threads/upmap-q-a.22298/ - is the solution to fix it for good.".

This little 850 Special is deceivingly agile and torquey. Absolutely LOVE the curves on this bike. It is very well balanced and my go to for fun riding!