Water Crossing / Carb vents

Just did my deepest water crossing yesterday and the bike started bogging pretty badly mid-stream and I barely made it across. Initially, I thought it was because I hit it too fast and simply got too slow for 2nd gear, but now I wonder if my problem wasn't that my carb vent lines were under water and therefore the bike was not getting fuel. It died totally just as I got ashore (whew!!) and started fine thereafter and the air filter was not wet. At deepest, the water level was probably about 1/2 the way up to the airbox.

What have you guys done to keep your carb vent lines open when the water gets deep? Do you put Ts in them and run a branch to the airbox?



I just installed the Extreme Weather Carburetor Vent Kit from Kevinscycleracing on my bike to keep both dust and water out of my carb.

There are several ventline filter kits available. But the solution to the vacuum lock on the carb is to route two of the lines to the airbox or under the tank. That way they will get air even when the other two are blocked by the water level.

I haven't yet looked to see where they all go, but does it matter which 2 go up and which 2 stay down?

Also, has anyone added a T to each line so that the bottom part can be left where it is, but so a branch could be added upwards? I saw this mentioned on a KTM forum. Seems like it would work until water got over the T, then both could be blocked due to water going up the lower line.


Thanks again Keith! I read his site when I first got the bike and remembered that he'd added a filter, but had forgotten that he was also addressing the water crossing issue.

I did the Ramsey mod and put the 2 carb lines in the air box quite a while ago.. has been working wonderful and never a problem..

Thanks everyone. I routed the 2 upper carb vent lines under the tank (to avoid any potential problem that Kevin's cycle racing speaks of with airbox routing) and went through the same creek that prompted this thread and all is well. No bogging!:thumbsup::worthy:

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