Oil Pukeage

10 replies to this topic
  • Vail yz4

Posted July 23, 2005 - 03:34 PM


Hey guys,

So I've only had my bike a little while and so far everything has been great. Today I'm riding at the track in the insane heat, probably about 100 degrees, and when I stop I look down and my left boot and the bottom of my bike have some oil spray on them. It turns out that the thick black hose that runs from the top of the motor down the frame and empties down by the gear shift is leaking some oil - havent had any time to look around, but any preliminary ideas? Not a good sight. :applause:

Thanks guys


  • grayracer513

Posted July 23, 2005 - 04:10 PM


Usually, this happens to this degree due to having too much oil in the engine. You did not specify your model, but the amount required to cause excessive oil expulsion at the breather is some where near 2 qts. Often, that is a result of failing to drain both the frame and the crankcases during an oil change.

I don't know if that fits your situation or not, but some oil will normally be blown out through the breather, particularly when you run it hard.

Other things that would cause it are excessive blow by due to weak rings, but if it's a newer bike, or is in pretty good shape, this is probably not the case, especially if it doesn't smoke much.

  • Vail yz4

Posted July 23, 2005 - 04:25 PM


Thanks Gray, it's a 99 400f. Overall very good shape. Ridden it probably five or six times at the track so far and haven't seen any oil come out there before, that's why I was concerned. It was really hot today and I was riding really hard, but up until I noticed the oil and killed it it ran totally normal. Definately not overfull after the oil change, it was my second track day on the oil and checked it this morning before going out and it was perfect. Definately gives me an uneasy feeling because I haven't seen anything come out of there before.

  • MisterMan

Posted July 23, 2005 - 08:29 PM


my new 2002 426 does the same thing.......I need to get a shop manual.....:applause:

  • Vail yz4

Posted July 23, 2005 - 08:36 PM


Anyone have a ballpark of how much oil is normal to come out of there on an extremely hot day riding hard for a few hours? I think that there's no way it's normal because it's never happened before and the oil is definately not overfull. It was enough to thinly coat the bottom of the frame/side of the tranny case and put a thin layer on my boot.

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  • MattyH

Posted July 24, 2005 - 04:22 AM


have you dropped the bike on its left side? if so oiol can travel up the cam chain tunnel and flood the top end with oil causing excess oil to drain through the breather hose. has happened to me a couple of times after dropping the bike on its left hand side.

  • Ga426owner

Posted July 24, 2005 - 06:10 AM


A little leakage is normal -

Excess oil = excess leaking

  • spdfrek

Posted July 24, 2005 - 10:48 AM


my 05 450f does it every now and then.As its a breather hose for the motor,I'm not to concered.My sb 350 would also do the same thing when it was revved high.Would coat the entire top of the valve cover with a light film from where the breather was at.As long as my oil level is good,I don't worry about it to much.

  • Vail yz4

Posted July 30, 2005 - 10:06 AM


Alright guys....guess I am going to attempt my first ride since this incident. Nobody that I've talked with seems to think I should worry too much, so I guess I'll just keep a very close eye on the oil and how it's running and hopefully it doesnt happen today, because it's about 20 degrees cooler today than last time...Wish me luck, hopefully I won't be posting on here later today about how my motor is blown up....

  • MisterMan

Posted July 30, 2005 - 11:47 AM


it droped 20 degrees already!!! wow, I wish it would do that here in the valley.

  • Vail yz4

Posted July 31, 2005 - 03:15 PM


Sick - two days at Thunder Valley and no oil out of the breather hose. :D

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