Removing California emissions on 87 VFR

I have an 87 California spec VFR, it still has the canister and all associated emissions lines with it. A few years ago, I remembered seeing a procedure to remove it all. Can anyone direct me in the right direction as to where I can find it?

Thanks!

 

Not really.

I live in non-CA state, so...I don't need to worry about emissions at that level. Aside from that, 10 years of looking at the rusting emissions canister is really wearing on me.

 

The 80's CA emissions stuff is rudimentary.

I don't think there is much more than the carbon canister for trapping evaporated fuel for redirection to the Carburetors. Other than that contraption I do not think there is much difference between CA and the 49 states model.

The vacuum canister is sort of heavy but its not taking any real power from the bike except as added weight. The fuel tank is plumbed to capture evaporated fuel and direct it to a tube that is connected to low pressure draw from the "vacuum canister". The low pressure source is a line that goes to the carburetors/intake manifold where it connects into the vacuum side of the manifold. There is a valve attached near the carburetors that shuts off this line. This may be a safety valve. It's a black disk about the size of a silver dollar and maybe a 1/2 an inch thick.

There may be a complicated set of lines and some hose to make turns around the carburetors in order to pull evaporated fuel from the carburetor float bowls. But I think it was more a case of the Carb float bowls having vents that were plumbed to allow evaporated fuel from the float bowls to vent into the "air plenum" beneath the air filter(s). The 'air plenum" is made of metal and holds the 4 carburetors in position with some phillip head screws that are usually a bear to remove. The float bowls vented into the air plenum and if a needle valve get stuck open there was a possibility that fuel would fill the bowl and escape out the vent and dump raw liquid fuel into the air plenum. It was sort of a fire hazard.

I think the big difference between the 58 and 59 (31 and 32) Keitiin's is that the CA model carbs have the float bowl vents and the 49 state carbs don't, but I may be wrong there.

As for the canister, removing it requires that you block off the line from which it gets its low pressure bleed. You should also block off the vapor line coming from the tank. This results in a tank venting problem. I suppose you need to investigate what the 49 state model bikes did re tank venting in the 80's. However, I am sure all 50 states now use some sort of charcoal canister and system to capture vapor that collects inside the fuel tank. The vapor ends up being recycled through the motor and burned. All the canister does is hold evaporated fuel and then give it up to be burned when you start the motor up after sitting for a period of time. I doubt that it affects performance unless the line from the low pressure tap cracks due to age and is never replaced. Then it acts as a vacuum leak. The biggest issue is the dead weight of the canister.

Check it out?

 

didnt think they wieghed all that much...you male it sound like the things weigh 20 lbs..

 

It's heavier than it looks, try taking it off for yourself.

I'm not advocating taking it off. I'm only saying that its really innocuous if you consider what it actually does. I won't tell someone living in a state where it was not required that they have to run with it, but if they do I doubt that they are going to have significantly different performance as a result of keeping it. The real problem is in NOT doing the maintenance necessary to keep it functioning propertly and inadvertently having a vacuum leak as a result.

The more problematic issue is the float bowl vent in the California Carburetors. That can end up with a fire if the bike is abused and neglected.

 

Did you notice the tubes sticking up into the plenum?

When you took the carbs off the bike you probably left then attached to the metal plenum with the rubber velocity stacks still attached. Did you notice the gold finished covers in between the two carbs per head? Those covers, inside the plenum, cover the vents from the float bowls. Each heads carbs share a T tube that vents into the plenum. Some of the hose lines that twist around and between the float bowls are fuel lines. Be Careful.

I heard that No. CO got dumped on by an early snow storm? Did you get wet?:biggrin:

 

I don't think yours is different.

On page 167 of the Clymer manual there is a diagram of the Evaporation Control System (ECS). The ECS is merely a system for recirculating the vapor collected from the tank. The drawing (#62) is a bit confusing because of some modifications in the drawing related to its simplification of the real thing. At the bottom of page 167 is another drawing (#63). This is a better representation of the PCV valve. In #62 they write out the name of the valve "Purge Control Valve". This valve has 3 lines running into it. The drawing below it shows the "hocky puck" looking thing as having 4 lines running into it. The ‘PCV’ is the purge control valve, is the “hocky puck”. They are all the same things. The #62 representation shows the line out of the PCV as one single line that subsequently splits into two lines going into the cylinder head inlets downstream of the carburetors. Actually it should show the outlet splitting into 4 lines, one for each carburetor. The drawings leave something to be desired. The representation of the carburetors is as diaphragm housing with a spring extending into the inlet of the carburetors. The drawing was obviously done by someone who knows next to nothing about the carburetors or how they look in cross section.

Here is the low down. The charcoal can is merely a receptacle for storing vapor overnight or during the time the cycle is parked. The PCV valve is operated by a vacuum diaphragm that utilized the low pressure of the #3 inlet port by tapping into the #3 intake port at the same threaded hole used for installing a carburetor balancing line. When you start the cycle the vacuum in the #3 intake port down stream of the carburetor, opens the PCV valve by creating suction on the diaphragm in the PCV valve. The low pressure in the general manifold of both the 1-3 bank and the 2-4 bank would suck the vapor in the charcoal canister into the downstream side of the manifold. The #62 drawing calls the vacuum line going to the #3 intake port the "p.c. port". It appears that the outlet side of the PCV valve goes to the side opposite the p.c. port. That is another part of the confusion of drawing #62. ( Note: if you look back at drawing #61 and you will see them pointing to the diaphragm-spring things and calling them carburetors.)

I have looked at my Keitin 59’s and they have the suction ends of the outlets coming from the PCV “hockey puck” going to brass tubes that fit right above the throttle rod drill holes. Each of the 4 carburetors is fitted with a small 90 degree bent brass fitting that ports to the low pressure side of it's respective carburetor's closed butterfly valve. When the motorcycle is started and throttle plates (butterfly valves) are closed, the low pressure builds up to just behind the closed plates. With the plates closed the manifold pressure is at a minimum (lowest pressure) at each inlet port. This is when the #3 tap for the vacuum line that operates the PCV diaphragm is at its maximum suction power. The PCV diaphragm is wide open at idle and the evaporated gas trapped in the charcoal canister is sucked into the cylinder head inlets behind the closed butterfly valves along with the idle mixture. In the early morning when the walls of the inlets are cold the vapor sucked in actually helps to start the cold engine.

What power does the Evaporative Control System (ECS) rob from the motor? Essentially nothing. The only work being done is the opening and closing of the PCV diaphragm. The small ports that allow trapped evaporated gasoline to be recirculated into the cylinders to be burned is not an added burden on the fuel system. If you think about how the Evaporative Control System (ECS) works you will realize that as you open your throttles and the pressure differential between the outside air and the air in your intake manifold becomes nearly equal, that essentially no air or evaporated gas will enter via the taps down stream of the throttle butterflies.

The fact that your Vf 500 had 2 "hockey pucks" is an indication that someone who did not want to take the tank off and mess with the split outlet lines messed with the ECS. They got a second ECV (hockey puck) so they only had to pull the line that went to either of the cylinder banks in order to close off the ECS ports. Why? Because when the ECV is not hooked to a inlet port (vacuum source) the valve is closed and no vapor/air will enter via the ECS ports.

Since you don't have a charcoal canister you need only plug each of the little 90 degree turned brass fittings that are above the throttle shafts on each carburetor to disable what was essentially an innocuous piece of emission control.

The remaining bit of emission control is, as I said elsewhere, built into your carburetors. It is a vent that allows vapors that arise from inside the float bowls of California Keitin 59 carburetors to vent into the air plenum.

 

Sorry, Vfrf2, I think TinkerinWstuff and I have kind of moved in and used your thread to discuss removing the Evaporative Control System (the evap canister and hose etc) from the Vf500f. I will move it over to Tinkerinwstuff's thread on having a flat cam.

 

my bike has the emissions can on it too. HOW DO I GET THAT CRAP OFF???

 

ah. So basically, if it aint broke dont fix it?

I just really hate the lok of that bigass can on the front of my motor. And since my plastics were decimated in my last low-side, it's stuck out there for all to see...

Guess replacin' my plastics is order of business #1 eh?

 

I just got a new petcock for my tank today, along with my new fuel pump relay. As soon as the carbs are synched, and I'm convinced the bike is running OK...it's going to come off. I don't need it, less crap to go wrong.

 

Don't take it off.

All it does is capture vapor that arises in the tank and in the float bowls and recirculates it through the carbs to be burned. If you take it off you'll be in violation of the law and be venting unburned gasoline vapors into the air. If you take it off and don't shut off the ports in the carbs properly you might end up with a vacuum leak at one or more carburetor. Be careful. It might be easier and safer to just maintain it. It takes no power from the engine and only adds the weight of the canister, the PCV valve, and the hoses.

 

If I violate the law, it wouldn't be the first time. I'm not in CA, so...the emissions are not required here in my state, at least for this model year.

My thinking is that it's less crap to go wrong. What if a component in the emissions system takes a dump? I'm sure as hell not going to spend one damn dime to correct it, I'd rather remove it first.