Breather Re-Routing how To?

I have searched and it has come up with a load of different threads but still I am non the wiser. On my 2002 WR 400 (UK) I am wanting to re-route the breathers from the carb to help with river crossing but am wondering if there is anywhere I can find a start to finish how to guide or even if someone can give me good advise on how to do this?

Also on the left side of the bike (as its sat on) there is a black hose at the front near the casings that is always splurting out little amounts of oily crap lol. I think this is the crankcase breather but not sure, anyway, is there a reason its spurting stuff out and if so can I stop it or re-route it

Thanks guys

Yep, that black hose dribbling oil is the crankcase breather. When I bought my bike, the previous owner had routed that and the carb lines up over the airbox cover getting oil everywhere. I rerouted the big hose to just over my chain...either way, just route it somewhere that it's not a prob for oil to leak out. And/or don't stop the engine in deep water. You may need to get extra line. Good luck!

Thanks, think over the chain would still be a bit too low to be honest but will find somewhere nice and hight where it cant make things all dirty. Do you know anytihng about the clear ones that come from the carb and whether I need to do anything to them? I have read there are 4 and no need to T them as that is done in the carb hence there being 4, so it says take 1 from each side of the carb and re-route and the other two leave but where should I re-route them to? Would it be okay going into the air box. Also the crankcase breather, is there any probelms with this going into the airbox or would that just contaminate the air fuel mix?

To prevent the long vent tube from sucking up water, i put a small Tee in the hose near the valve cover. Ever have a straw in your drink, and it has a crack or hole somewhere in the middle? Its impossible to suck the drink up the straw.

Thanks, think over the chain would still be a bit too low to be honest but will find somewhere nice and hight where it cant make things all dirty. Do you know anytihng about the clear ones that come from the carb and whether I need to do anything to them? I have read there are 4 and no need to T them as that is done in the carb hence there being 4, so it says take 1 from each side of the carb and re-route and the other two leave but where should I re-route them to? Would it be okay going into the air box. Also the crankcase breather, is there any probelms with this going into the airbox or would that just contaminate the air fuel mix?

My carb lines were already done when I got it, so I don't know where any T's were added...but they do run up over the airbox and seem fine up there. You will need to get extra line for that, I believe. The crankcase breathers are known for spitting oil, so I wouldn't run it into the airbox. Thumper blokes idea seems perfect.

Rabbityracer, do all of your carb lines run up over the air box or just two from either side?

Hi mate,my '00 sucked in water and stalled the first time i went through a river.

Just re route the upper hose from each side of the carb to the top of the airbox.

The later models have t pieces on them.

With the crank case breather,i just cut a small hole in the hose near the rocker cover gasket so air can get in when the hose is submerged.(i one day mean to fit a T- piece,one day)

I'v never had a problem since i'v done this mod.

hope this helps.

My carb lines were already done when I got it, so I don't know where any T's were added...but they do run up over the airbox and seem fine up there. You will need to get extra line for that, I believe. The crankcase breathers are known for spitting oil, so I wouldn't run it into the airbox. Thumper blokes idea seems perfect.

The crankcase vent line should go into your airbox... Yamaha made that option stock in 07'. Search the forum, there are plenty of threads with pics on how to do it.

If you submerge the bike with the CCV line under water and engine off, just get off and push the bike out of the water... it will suck water into the crankcase if you try and start it submerged.... this I know while riding my 04' a few years back :confused:

669348#28881703-M-LB

mine is routed up over and around the carb along the top of the fame then down the RH side of the sub frame. it is vented to the area between the airbox and the RH side cover. makes a bit of a mess but better then sucking water or venting it in the air box

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