Took my DT250B for a backroads adventure of just over 70 miles. This bike has always smoked a bit more than the others in my herd, and the check valve on the pump has a minor seepage issue. But I have left it as is assuming that too much oil is better than not enough, and the bike runs fine.

Well it smoked quite a bit on this ride. There is a short section of paved 55 MPH speed limit in which it smoked like crazy. Nothing but a blue haze in my rear view mirror. When I took a break at a local park I noticed my sight glass showed NO OIL in the tank. I tipped the bike slightly and saw that it was just below the fisheye, so I rode it straight home from there.

So this 70 mile ride nearly sucked down a full tank of oil. Should I send it to DEET and let him work his magic on it? Especially since the check valve is leaking a bit. Or is there something I can do, not knowing anything about the possible adjustments?

I think I know the answer……

The factory service manual shows how to adjust the oil pump, it should be downloadable from this site.

I would check adjustment first.  There's the shimming for minimum stroke.  

The most common thing I've found for situations like yours is the cable adjustment.  It's important to twist the throttle until the throttle slide just starts to lift before you align the pulley marks at oil pump.  

I've seen pump cables (and throttle cables) adjusted so the pulley marks appear aligned when throttle grip is released.  But then there is enough slack in the throttle cable so the pump pulley is way past the alignment marks before the engine comes off idle.  Result is way too much oil because for example oil pump thinks you're at 1/4 throttle when carb slide is still at idle.

Thanks PAHIKER (Duh!)

The manual is now on my lap and I am ready to learn……

Thanks MarkT,

I will go check the cable adjustments and report back.

Pin was way out of alignment to the mark on the pulley. Cable adjustments made per MarkTs method. Also verified minimum pump stroke is to spec at closed and open throttle. It appears to have solved the excessive smoke and hopefully reduced the consumption.  It still has a slight blue tint to the exhaust when throttled hard. I gotta say I’m still a little nervous to do a long high speed run……but will do so tomorrow. It’s raining at the moment.

Well I did a 10 mile test run with some duration at 50 MPH and all seems well again. So I planned to use the 250 as one of the bikes in a group ride yesterday and of course I now have a new unrelated issue to resolve. Since it is unrelated to this oil consumption issue I will start a new thread asking for help with my trouble shooting…….. Have I ever mentioned how much I appreciate all your input and suggestions? Well I do. Very much so.

Just as an FYI, another thing to check is if the cables, particularly the oil pump cable, are seated correctly in the splitter housing. When I first got my DT250 the oil pump cable was not seated all the way down into the splitter housing causing the adjustment to be way off.

My oil consumption problem has been resolved. The problem was my own doing. I had incorrectly adjusted my throttle cable to eliminate free play at the grip. In doing so, I messed up the correlation between the oil pump cable and the throttle cable. All is well now after being educated by the best of the best here on this forum.

We've all been there. There is two ways to do something, right and again. I've done my share of "again".