FCR Vent Tube Re-Routing

OK....so I have had the bike stall a few times in creek crossings that were only about 8-10 inches deep.....The cause seems to be the carb vent tubes....I'm going to re-route one of the vents....for those who have done the same, did you find it better to run up towards the front or back over the airbox? Vent tubes are long enough to go either way......

Thx

I route up under the tank.

Which ones to root up and which ones down?

Each vent goes into a "T", so I route the upper hose from each "T".

Each vent goes into a "T", so I route the upper hose from each "T".

If willing we could have a good discussion on this (routing). I have thought about it a bit and have a couple of ideas. They may be crap or they may be decent....

If willing we could have a good discussion on this (routing). I have thought about it a bit and have a couple of ideas. They may be crap or they may be decent....

Lets hear it.......:lol:

I have also had the bike sputter while having to go upstream, for a couple of hunderd yards, in a not terribly deep stream just down from Taylor Lake.

Right now there are 4 vent tubes going down underneath the bike correct (2 vents, each "T"ed creating 4)?

As long as all 4 are underneath the bike and in water, the carb can't vent properly but water can not go up the tubes towards the carb.

If you route one tube from each vent, you have created a place for the air to escape. So if you go into deeper water, the water is going to be able to go up the bottom two vent tubes while air goes out of the top two vent tubes.

Making sense? Or am I full of it? I am remembering some of the pics I see of DRZs in fairly deep water.

Well.... that is true. If the water is deep enough to be over the "T", water will most likely enter the carb. But, if all the hose are routed down, you may well stall once the four hoses are submerged.

If you want to prevent all this, route two up, route the other two down to a catch can and then route the catch can vent up. You'll be able to ride constaly in water till the airbox fills.

Well.... that is true. If the water is deep enough to be over the "T", water will most likely enter the carb. But, if all the hose are routed down, you may well stall once the four hoses are submerged.

If you want to prevent all this, route two up, route the other two down to a catch can and then route the catch can vent up. You'll be able to ride constaly in water till the airbox fills.

Exactly along the lines I was thinking. Except I was thinking route all of them into a catch can and route the catch can vent up. :lol:

Well.... that is true. If the water is deep enough to be over the "T", water will most likely enter the carb. But, if all the hose are routed down, you may well stall once the four hoses are submerged.

If you want to prevent all this, route two up, route the other two down to a catch can and then route the catch can vent up. You'll be able to ride constaly in water till the airbox fills.

i hope i don't seem like a blathering idiot, but what is a catch can and how would that work?

What type of catch can would you use? and where/how are you thinking to mount?

......and it sounds like by simply rerouting a vent(s) that the carb would not draw up any water in a shallow crossing??? (water level below the air box)

Routing the two up, you can go in water to just below the 'T' safely.

A catch can is a container with five ot more nipples on it. Each breather gets connected to a nipple. A hose gets placed on the fifth nipple, and extra ones would be capped off. Any fuel from the carb would flow into the the can. The nipple where ity enters the can would be well above any fuel the can catches, thereby always having the hoses vented to atmospheric pressure, ensured gy the fifth, open hose, routed inder the tank.

Being I am a weanie and am never in water more than a foot or so deep, this is fine for me. You'd have to do some searching for a suitable item. You want to ensure it can easily hold a few ounces and be sure to empty it after a rise or a lot of falls.

sorry if this is a stupid question, but why couldn't you just route all 4 to a higher point and be done with it? like route them up past the air intake and out under the rear fender?

Because they vent the carb to atmosphere... and .... the vent fuel vapors and in some cases, liquid. If all the hoses went up, the hoses could become liquid filled and they would not longer be providing and atmospheric reference pressure.

Because they vent the carb to atmosphere... and .... the vent fuel vapors and in some cases, liquid. If all the hoses went up, the hoses could become liquid filled and they would not longer be providing and atmospheric reference pressure.

that makes perfect sense. could you keep them going downward but just make them shorter?

You could, but you'd still be limited by the bottoms of the hoses. Routed two up, two down you can go as deep as then 'T' before a bad day begins. To go deeper, you need the catch can rig.

makes sense.

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