Oil Problems
 

I'm reading up on the old posts here because I'm burning oil and trying to figure out why. I'm not familiar with pulling apart engines, so I have some questions before I start doing so.

First my situation -

• 1998 Superhawk
• Since my last oil change (800 miles ago) I've put in 2 quarts.
• 36K on the bike; 28K when I bought it a year ago. Oil Change every 2.5 - 3K
• No viasble leaks, no oil spots on my garage floor or on the bike as far as I can tell.
• A small amount of oil in the air box (my first question)
• Small air filters (foam) were pretty much disintegrated when I pulled the tank off. Main filter was dirty, but intact.
• I never noticed any smoke, but I'll have to check again when I get the tank back on.
• Pretty clean bike otherwise, pretty much stock.

Starting with oil in the air box... how does oil get into there?

Any other suggestions of things to check are welcome.

-Pete

They all seem to use some oil anyways, not 2 quarts every 800 mi though. Where you the last one to do an oil change? I am asking to make sure enough was put in to begin with. There is 3 typical places to loose oil, a leak (drips on the ground), past the rings (Blue smoke) and through the valve seats (gummed up plugs). Otherwise the airbox drags some but it should drag that much out. More info is needed.

The oil in the airbox is likely to be normal... Just a few droplets, a slight sheen in places... You have the crankcase vents and such ending up in there...

Using a little oil is rather normal, but not that quantity... Unfortunately apart from the three ways cornandp mentioned I dunno any other ways to lose oil...

I did the oil changes myself, so I know it got oil. Good point though.

The oil in the airbox was more than a sheen. more lake a tablespoon or two.

When would you see the blue smoke? Would you see it at idle, our would the bike need to be revved up to higher rpm?

I was kinda gearing up to do the valve seals, but still hoping to avoid if unnecessary.

Thx guys

Sounds like blowby to me, though I've not heard of a VTR that crapped its rings after only 36k....unless someone did something bad.

Do a compression test. Ensure the engine is warm when you do it. That will tell all.

Oil in the airbox comes from the crankcase vents, I see a few reasons why it gets there.
First and most common is oil overfill, someone who is leveling oil while on the side stand will get this kind of problem from the crank whipping the oil sending a mist in and out of the case vents (common pin twins pump a lot of air in and out since both cylinders go down almost at once). the oil is then ingested by the engine.

Second, oil is level, but the cylinder blow by is too important and literally blow the oil droplets out of the case vents to the airbox.

Third and none the least, at night someone is taking a cup of oil, remove the tank and airbox lid and pour it directly in there. Beating up the neighbors at random usually fix this :D

If you overfill the crankcase the excess will get blown up into the air box. On my bike anything more than 3/4 of the way from the bottom hash mark to the top one seems to be excess.

Still, I don't imagine that would account for 2 qts. in 800 miles.

Also replace the two small foam filters in the air box. No this wont help with the oil problem but it is where the carbs pull air for the back side of the slides and with out them you will end up with a whole new set of problems.

Try a different oil in your bike. I had a BMW that used a lot of oil with a couple of brands, but was fine with others.

when i first got my superhawk it had mobil 1 in it, i had to add oil almost everyday. changed it out for some rotella t, which is what i usually use, and its been staying level now.

Grab a compression tester (you might be able to borrow one from your local auto parts store) and test both cylinders. Then test with a couple squirts of heavy oil in the cylinders.
If the compression is low without oil and normal/high with oil, then your rings are bad. It should only take a couple of minutes and will tell you a lot. However, I would think you would see smoke if its burning oil, so it might be dripping while your riding (some kind of seal opening up at higher speeds: it happen on my Accord).

You do have a thread plug in the oil drain hole right? Or do you have a nice custom one; perhaps a shaved down wine cork?? :)

I'd say that's part of your problem - motorcycles should have the oil changed every 1000-1500 miles. You should pull the plugs and see if it's been burning it. While you're at it I'd also recommend the suggestion about checking the compression. A little bit of oil in the air box is normal and totally ok, that's probably not where your consumption is happening. Valve stems or piston rings would be my guess. The compression test would rule out one of those!

If you do this test. make sure that you perform it with the throttle all the way open and the slides blocked up :)

You don't need to block the vacuum slides up, but holding the throttle wide open is a must. It's an easy experiement trying it with the throttle closed - it makes a big difference. Also, the spec numbers are with the engine hot. I've also found that to make about a 10-15psi difference, hot being a higher number.

I have a ? My 01 is full of oil and shutting off when the oil light is blinking my bike only has 14 k on it and is very clean anyone out there know a fix or the problem?

R/R?