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Discussion Starter #1
Today I removed the emissions system from the Monster. It was a rather simple procedure and I like the way it cleaned up the bike.

After disconnecting all the hoses and unbolting the cannister I removed them. Then I removed the two brass hose fittings from the intake manifolds. To plug the holes I used two brass 5mm screws (slotted heads) and aluminum crush washers from a spare rack of Keihin carbs that I use for parts on my CB750s. These screws are used to plug the vacuum ports used for synching the carbs. Another option would be to get a pair of 5mm stainless allen bolts with short shafts and use the crush washers from the brass hose fittings. I did not use any Lock-Tite or any other sealant as my experience with the CB750s tells me none is needed. They simply don't leak. Also keep in mind that the emissions system is an open system (it draws air through the hose that lies along the right side of the engine).

For the fuel vent I used some 1/4 inch rubber fuel/vacuum line I had lying around. I attached one end to the fitting on the tank and snaked the rest down the back of the engine along side the overflow line then trimmed to length.

I test rode the bike and it runs just fine.

Next will be the fugly grey pods which are nothing more than an intricate carb venting system.
 

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Both procedures are common among the Monster crowd. When you get the side pods (3 hoses from the carbs terminate there) be sure to leave the small filters attached to the larger carb vent tubes (they're acually not "vent" tubes in the strictest sense, but what the heck). There's usually enough tubing to tuck them in behind things so they're not visible. The other one you can put any number of places to get it out of the way. Sometime when you have the air box off you can do a better job of relocating all of them.
 

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Discussion Starter #3
Sometime when you have the air box off you can do a better job of relocating all of them.
Yep, I think I'll wait until I do the jet kit to remove the pods. That way I can decide what to modifiy, what to leave and where to route it.
 

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My pods proved to be filterless. I understand that is common for many of the later carbys; Ducati didn't bother with them ;D
 

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My pods proved to be filterless. I understand that is common for many of the later carbys; Ducati didn't bother with them ;D
Hm... Mine's a 98 M750 and has the little filters. Does anybody know if they're little charcoal filters? Typically in older bikes that have vented carbs, such as Keihins, the vent lines are not filtered and run to some strange place like the area above the airbox and just hang there. Also, these lines are huge compared to those of older machines.
 

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Here's the story as I got it from Bruce at BCM who got it from the factory....

The "vents" are to provide an atmospheric pressure reference for the back side of the diaphragms (I knew that)

The filters were installed to pass a California "bag test"

The pods are to hide the filters.

The "bag test" is a passive emissions test in which the bike is run on a dyno (without a fan) 'till it's hot as a mofo. Then it's put in a sealed "bag" and all the hydrocarbons emitted are collected and measured.

Carbed bikes are just gonna have a problem with this test. They've got float bowls full of gas and a vent to atmosphere (the diaphram doesn't really seal the reference from the venturi side because the needle goes through it (the slide actually) and there are holes in the slide to damp it so it doesn't bounce around like crazy when you crack the throttle).

The filters helped contain some of the vaporized fuel so the test could be passed.


The important thing here is that you don't need the pods AND you don't need the filters. Just tuck the hoses out of the way someplace where the wind screaming past doesn't create a vacuum.
 

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Discussion Starter #7
The pods are to hide the filters.
They must have done at least a couple of different ways. My filters are attached to the lines about 3 to 4 inches below where the lines attach to the carbs. Then a line attaches to each filter and they go on from there to the pods. I haven't really spent a lot of time tracing them yet.

Thanks Don, for confirming what I originally thought. This board is the greatest. :D
 
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