xr 400 smoking

Guys I just picked up 97 xr 400 at a cheap price. It was in storage for two years. It runs good but it smokes white smoke constantly. It is blowing oil out the exhaust as well. I checked the valves they are in spec. I changed the oil and only put in under 1.9 qts and checked the level and it's good.

I cleaned the air filter thoroughly. The bike runs strong. I have not done a compression test but I know it's either the valve seals or the rings. What is your best guess? I have run the bike for a while in the woods and really ran it hard hoping the seals would swell or the rings would unstick if that were a problem.

Let me know what you think. Smoking in Pittsburgh.

What exhaust does it have on it? Stock or something else?

White smoke usually says "water or coolant somewhere it shouldn't be" to me, but since the XR doesn't run coolant....................

When you changed the oil was the old stuff milky or gray looking?

It has pro circuit exhaust. It was not milky but could have been gray. When I changed the oil it was low because of all the oil its blowing out the exhaust. The oil didnt' look good but it didn't have any metal in it? I am really thinking it's the rings and if I am going to replace them and take the head off I am going to replace the valve seals. I just wanted a good opinion before I take the head off.

If it's not overfilled and it's blowing oil, I would say rings too.

Does the Pro Circuit use a packing or is it baffled? If a packing, if it is water/oil soaked you might get some while smoke.

The pro circuit is just baffled. I think I will take the head off over the holiday weekend and look at the size of the piston to order the appropriate rings.

If you have any more advice let me know thanks.

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