wr450 06 cutting out in water


Last couple of rides I have been on if I get water up to the top of the engine cases the bike dies.

Wont start again until dragged out of the water - sometimes takes a while to get started and runs a bit ragged for 30-60 seconds and then runs fine. Air filter is bone dry before and after this happens - all wiring is above case height. I'm confused.

Could it be sucking water into one of those carb breather hoses??

The breather hoses are under water so they are starving the carb for fuel. If the carb can't breath then the fuel won't fill the bowl and the bike will stall out. I highly recommend puting some 'T's in the carb vent lines and running the extra end up to the steering head so the carb can still breath when the bottom hose are submerged. My .02 -- WR Dave

Thanks for replying Dave

Two of the carb breathers had tees in them - the teed hoses went down to the back of the motor like all the others - how dumb is that?

I rerouted the teed ones into the airbox

I'll go an play in the water over the next couple of days and see if that fixes it.

thanks again


Routing the ends of the 'T'd hoses into the airbox is OK, but you must be careful when washing the bike to not get water going down the hoses or if you lay the bike over , you could wash down your air filter with gas from the carb bowl. I installed 1 'T' in each of the crossover vent tubes and ran the extra hoses I installed up to the steering head. Just be sure to install the "T's below the top of the crossover and on the drain to the ground side of the hose. THis is a pic of my old WR 426. One other thing, you didn't say what year your bike was. If the bike has a breather hose from the valve cover to the bottom of the frame, then don't try to start it when this hose is under water as it will pull water into the engine while starting. I 'T'd that one too. My .02c solution. WR Dave.

Carb vent crossover "T's


Crancase breather 'T'


Thanks for the photos.

Mines an 06 with the engine breather going into the bottom of the airbox (which caused me grief when the airbox was full of water).

I'll re-route the breather hoses up to the front of the tank - I don't want petrol on my air filter....

thanks again



You will need to put in the "T"s if you route to the top of the frame due to the fact that washing could run water down into the carbs with out the 'T's installed. I recommend puttin the hoses back down where they were and running a new set off the "T's up under the tank. Also you could move the breather hose to the top of the airbox if you have removed the AIS kit. WR Dave.

i ran two new hoses from the carby to the airbox and fitted the ends to the bottom end of a plastic 500ml oil bottle .i have a piece of oiled foam in there and that stops water getting into the tubes it never misses a beat until the water reaches the coil wires which are on the right hand side of the frame on my old wr400 y2k. aquarium hose and garden spray nozzles worked very easily.beats draggin your bike from the mud and de watering every time

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