HELP! My "uncorked" XR650L with K&N filter is drinking water through the drain tube!

9 replies to this topic
  • HondaXR650R

Posted December 31, 2004 - 04:30 PM


I just I picked up a 2002 XR650L with 6k miles on it for $3000 and it's already been modified quite a bit... ;) White Bros E-series exhaust (sounds awesome, by the way) smog removed, K&N air filter, etc.

I ran into one BIG problem, though... :D I think the bike is actually DRINKING WATER! I rode the bike with no probs whatsoever in dry weather, but a few minutes after riding in heavy rain, the bike started acting like it had water in the fuel. :D The airbox was muddy & wet... It totally looks like the bike has been sucking water up through the drain tube and water is making its way into the combustion chamber! :D

:D Is this a known problem? ;) If not, I think I just discovered it...

;) Does anyone know how to fix this? ;) I feel like snipping the drain tube short like the tiny one on my "R" and hiding it in dry space against the front of the rear fender. :cry: Should I do this? :cry:

:cry: I believe that running a K&N filter creates enough of a vacuum inside the airbox to be sucking all this water from underneath the bike when I ride in the Oregon rain. :cry:

Somebody please let me know if I am making sense. And, tell me what to do... snip the tube and put the pinched tip back on? :cry:

:lol: Thank you in advance for any help! :D

Ride red!!! :lol:

  • ghoti

Posted January 01, 2005 - 05:48 AM


I've ridden my 04 L in the pouring rain without it missing a beat. I have a Uni filter and the stock, de-baffled exhaust. Are you referring to the airbox drain? I assume it's there so water will have a way out. Was it wet/muddy on the engine side of the filter? Could be electrical. Water provides lots of paths to ground.

  • XR650L_Dave

Posted January 01, 2005 - 07:47 AM


The airbox could be significantly 'depressurized' relative to ambient air if the snorkel is still in the airbox.
Check for a good seal along the lower edge of the airbox where the sideplate forms the airbox cover- mine wasn't sealing well.


  • ogden1488

Posted January 01, 2005 - 08:50 AM


what is the snorkel everyone keeps talking about removeing

  • ogden1488

Posted January 01, 2005 - 08:55 AM


i got an 05 xr 650 l and i put hot plugs, fmf q, k&n, dyno to set jets, simi syn oil, full hard susp set and cant wait to get her out of shop.. first service. soon skid plat and bark busters and fatty renthal enduros.. other sugestions welcome

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • Misfit

Posted January 01, 2005 - 08:57 AM


If you take your seat off its the little plastic peice on top of the airbox thats held on by 2 rivets. Just take a drill and drill the 2 rivets out and it will come right off.

  • woodsedge

Posted January 02, 2005 - 12:14 PM


I had this happen once on mine. The drain at the bottom of the airbox was clooged with mud so water came in in the dwonpour I was riding thru, but it couldn't get out. (A crash and slide had scooped up a bunch of mud with the airbox cover).

Check that the little drain at the bottom of the airbox is freeflowing.

  • nerd

Posted January 02, 2005 - 05:01 PM


The problem could be that the snorkle has not been removed, K&N filters offer nearly no resistance so it could be that the vacuum inside the airbox is so high that it sucks in air from every opening. Make sure the snorkle has been removed. Although the pinch drain pipe should be closed.

  • HondaXR650R

Posted January 03, 2005 - 12:51 PM


The airbox could be significantly 'depressurized' relative to ambient air if the snorkel is still in the airbox.
Check for a good seal along the lower edge of the airbox where the sideplate forms the airbox cover- mine wasn't sealing well.


THANK YOU!!! I believe that was the problem. I drilled out the rivets and removed the airbox snorkel. The bike is running better, too. :cry:

Also, to be safe, I shorened my airbox drain tube and put the end in the DRY space in front of the lower rear fender/mud flap so no matter what, my "L" will never drink water again!!! :cry:


:lol: [COLOR=Red]NOW EVERYBODY GO SNIP YOUR DRAIN TUBES SHORT!!![/COLOR] :lol: (if you have a K&N air filter and you want to ride in the rain or through creeks, anyway!) :cry:

  • llksta

Posted July 28, 2005 - 09:06 AM


Interesting converstations about drain tubes from across the water !
There should be two drain tubes in the airbox ( if it's set up the same as in the EU ),

One is a pinch drain, very short and drains the inside ( Dirty side of ) of the air filter, this lets water flow out ( that gets sucked in through the airbox opening / snorkel ) but doesn't allow air and muck to get sucked in as it's a one way reed valve.

The long drain tube drains the clean side of the filter of oil that's blown back from the crank case vent. This one should have a solid plug ( as far as I can tell ) or maybe a one mechanical valve at the bottom end, you have to pull this out every now and again to drain out any oil. If the plugs missing this would definitely suck up water and crud on a wet trail. !! And suck it into the cylinder. :applause:

It would be a bad idea to cut or shorten this tube for two reasons, your bypassing the airfilter and so weekening the mixture but worse your going to suck dust grit and other crap straight into the motor. When the trails dry up your going to have problems. :eek:

Related Content


Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.