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Griso Evap Can removal

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GTM®

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A re-post of my original data for those interested in this mod:

Remove front mount bolt:
GrisoEvap1.webp

Unbolt rear master cylinder:
GrisoEvap2.webp

and pull out of the way:
GrisoEvap3.webp

The rear evap can mount is a bugger to get to:
GrisoEvap4.webp

Remove the bolt:
GrisoEvap5.webp

And replace with a shorter one (or you aren't able to tighten it again):
GrisoEvap6.webp

Disconnect main line...:
GrisoEvap7.webp

that feeds the infamous (often faulty) tip-valve -- (leave if you wish):
GrisoEvap8.webp

You can use a piece of the rubber lines connecting to the evap can from one side to the other to make T/B balances easier in the future (recommended), or see below.
GrisoEvap9.webp

Or remove the fittings and plug with appropriate bolts:
GrisoEvap10.webp

Voila. Done.
 
StokedOnSpokes wrote:
Is there any advantage to doing this besides aesthetics? Does the HP increase?
Click to expand...

Hello; It will smooth out the throttle-ing 100%... I cross connected the vacuum taps (left to right) when I pulled mine off. I was still having some of the throttle response hesitation and slamming shut issues even with all the TB balenced and TB Zero'd.... Once I pulled that silly canister off... The whole throttle issue was gone!
 
by the way. the tip over valve on my griso was hooked to my transmission vent from the gas tank, luigi was working late that day
 
Re: Griso Charcoal can removal

I finally removed my canister after having idling issues. Never had issues until this year. It would keep dying on cold days, and once I got it going, the idle would go between 900-1300 rpm. No, I haven't done anything with the stepper motor yet.
Idles much better so far......
Only took about 30 minutes.

I did remove the tip over valve shortly after getting the bike 2 1/2 years ago. The garage was always smelling of gas and I had a huge rush of air sound every time I opened the gas cap. The problem went away after removing the valve. Maybe it was faulty, maybe it was installed backwards. At least it's sorted now.
 
Re: Griso Charcoal can removal

I have a 2009 8V Griso and would like to do this if it makes an improvement in how well my Griso runs. Quick questions:

- What size bolt do I need to replace the rear mount bolt for the canister (since I will need a shorter one)?
- What size bolts do I need to plug the manifold connections?
- What size bolt do I need to plug off the tip over valve if I remove it?

Thanks. Just want to get the correct, tried and true bolt sizes to save time and make this repair go smoothly. Would hate to have to keep running back to the hardware store in search of correct sizes.

-Drew
 
Re: Griso Charcoal can removal

1. you dont need to replace the bolt with a shorter one, just tighten it down real well.
2. mm6x1
3. Dont plug it, just replace the valve with a male-male barb (for 3/16 hose i think)
 
Re: Griso Charcoal can removal

The manifold bolts are standard M6 metric. I think the best way do do it is to leave the "valves" in the manifold and connect them with the rubber hose. Makes adjustments easier in the future, I believe. You will have extra hose on hand once the canister is removed.
I believe the rear mount bolt was a M8 by 12 or 20mm. I had old bolts laying around, so I just replaced with what I had on hand.
I just bought a barbed brass coupler to remove the tipover valve and left the hose dangle at the bottom of the bike with the others that it's attached to (battery overflow, etc.).
You would be best served to take the tipover valve and rear mount bolt to the hardware store for proper fitting just to make sure.
The rear mount bolt just needs to be slightly shorter, but have threads all of the way up to the head of the bolt.
 
Re: Griso Charcoal can removal

Thanks. I'll undertake this little project next week. :)

-Drew
 
Re: Griso Charcoal can removal

Didnt want to start a new topic just for this:

Does anyone have pics of this procedure? The ones earlier in the thread have expired.

Thanks!

---
Edit: Ignore me, I have a UK bike ;)
 
Re: Griso Charcoal can removal

Had stalling issues today, so I figured I'd try this removal and see how it works. Maybe this is an inelegant short cut but I did not remove the rear mount bolt. I figure I'm not using the plastic canister holder for anything so the simplest thing was to cut the plastic around the rear mount bolt. No busted knuckles. For those who want to use the space for smuggling than I guess you'll have to loosen that bolt. :mrgreen: For the line leading to the hose connecting the throttle bodies I just cut that hose short and stuck a bolt in there than taped it up with electrical tape.
 
Re: Griso Charcoal can removal

Well, I finally got around to removing my charcoal canister from my 2007 G11 (it was raining and I was bored). Turns out, it had never been installed properly anyway so wasn't fuctional (probably why it never gave me any trouble). The hose connecting the tank to the one-way breather valve (aka tip over valve) had never been attached at the tank. The hose connecting the manifolds to the canister was pinched under the battery box. The hose connecting the tank to the canister wasn't connected to anything, and just vented below the bike. Here is diagram of the system, the circled bits didn't exist, and the red rectangular area was pinched.



Question: Since the left-most connection to the tank in the diagram has never been connected, is there any reason to connect a venting hose to it now, and just have it routed down under the bike? Any likelihood of fuel exiting there?

Also turns out my battery box drain tube was routed back under the seat. At the end of that tube the paint had peeled off the frame. I've never had a leaky battery, but my bike was a demo and they gave me a new battery when I bought it, so I'm not sure what they had before. Fortunately the peeling is hidden in the tail section.

pic.webp
 
Re: Griso Charcoal can removal

erice said:
Well, I finally got around to removing my charcoal canister from my 2007 G11 (it was raining and I was bored). Turns out, it had never been installed properly anyway so wasn't fuctional (probably why it never gave me any trouble). The hose connecting the tank to the one-way breather valve (aka tip over valve) had never been attached at the tank. The hose connecting the manifolds to the canister was pinched under the battery box. The hose connecting the tank to the canister wasn't connected to anything, and just vented below the bike. Here is diagram of the system, the circled bits didn't exist, and the red rectangular area was pinched.



Question: Since the left-most connection to the tank in the diagram has never been connected, is there any reason to connect a venting hose to it now, and just have it routed down under the bike? Any likelihood of fuel exiting there?

Also turns out my battery box drain tube was routed back under the seat. At the end of that tube the paint had peeled off the frame. I've never had a leaky battery, but my bike was a demo and they gave me a new battery when I bought it, so I'm not sure what they had before. Fortunately the peeling is hidden in the tail section.
Click to expand...

1. The two lines that come from the bottom of the tank should be routed towards the ground. One is an air vent for the tank and the other is for overflow of gasoline.
2. Do you still have a battery in the bike that needs a vent hose? If not, you don't need a hose for venting the battery. I would put either sand & paint the peeling area or at the least, put some grease on it to stop any corrosion.
3. I remove the Evap system on all of the bikes I've purchased that had them and I always plug both of the tubes on the bottom of the throttle bodies. As an alternative method, you could just use one hose and connect those two ports together. I tried it both ways on one of my Guzzis and it didn't make a difference using either method.
 
Re: Griso Charcoal can removal

Thanks, I figured I'd have to route a hose from the breather to below the bike, but was hoping otherwise. Fortunately I have lots of leftover hose and clamps now. Removing the tank to find where to attach it looks pretty straightforward. Who knows, I may find more surprises.

The battery box has its drain hose intact so it's rerouted now to terminate below the bike. It had just been laid in the tail section before. It also managed to corrode a few bolts at the exit from that hose, but it was just surface rust. The paint that peeled is only the silver powdercoat, and the primer is still intact below it, which is fortunate.

I ran the tubes and connected the throttle bodies, since that was the easiest fix (essentially that's the way there were before, since the common hose connecting them to the canister was pinched).

It's not clear to me if it was a manufacturing problem, or if the dealer (they are no longer a dealer) tried to fix any issues caused by the pinched tube issue by removing hoses. Either way, its sorted now.
 
Re: Griso Charcoal can removal

I think that it's important to spend the time to run the vent line from under the tank all the way down near the ground to get the gasoline vapor away from all of the heat that's generated by the engine under the tank. Actually, you can get it to it fairly easily and just run it away from anything that moves like throttle linkage and route it down and away from the heat. It sounds like somebody did their own version of a disconnection of the Evap system before you got the bike.
 
Re: Griso Charcoal can removal

Thanks for the info in this thread, just gave my Griso a charcoal cannister apendectomy(sp) :D

Took me a little over an hour, since I work slow (since I am constantly grabbing the wrong size wrench). Also ran to the hardware store to get some misc stainless bolts.
 
Got around to doing this on my '11 Griso today. Previous to this, I had a loud swooshing sound due to vacuum whenever I opened my fuel cap. Also, it ran more poorly the longer I rode without opening the cap. So a noticeable improvement in drivability immediately!

This whole can thing definitely gets the dubious achievement award! It's a crazy amount of plumbing to, I surmise, trap the vapours that escape from the tank and vent them back into the intake system.

I suppose the whole thing would be relatively harmless, although fugly, except that "one-way valve" must have been bogus.

What I don't understand though is why the bike would run better immediately. I can see that it would run better after the vacuum had built up, but it is definitely better right off the bat! :blush:
 
I wonder if the factory didn't install some of the one-way valves backwards. My G11's tank didn't draw air in; it pushed it out when I opened the tank. I think the idea is that the valve lets air into the tank (which makes sense) but won't let vapors escape. After removing my valve I examined it carefully. One side is marked "toward tank" (I think) in German. The valve shuts when you try to blow air into the valve from the 'tank' side. But if you blow air in from the other side, the valve opens and lets air through. It should make a partial vacuum in the tank not occur, and would explain why some people here are worried about their tanks being damaged from expansion by repeated exposure to warm weather, bike sitting in the sun day after day, etc.
 
Hey guys, I’m about 2/3’s done with my Evap removal and am now confused! Plz help! I don’t understand the instructions on:
“You can use a piece of the rubber lines connecting to the evap can from one side to the other to make T/B balances easier in the future (recommended), or see below” from the pictures above

Specifically, the two throttle bodies are connected and they then t down to the Evap. I want to leave them connected for ease of balancing. Do I just plug the line heading to the canister? I’m confused. Plz help!
 
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