Sight Glass and Smoke

[who_gives_a6]

Went riding today and all was good and no issues. However, I've always been able to see oil in the sight glass on the frame. Today it was not visable. Didn't notice until near the end of the ride. Ran great and no notice so didn't concern about it too much.

Changed the oil when home since it was due and no excess amount, no mixing with trans, metal fragments, etc. Filled it up and saw oil in the frame again. After a short bit of running it is not visable and never comes back, regardless if on or off. Also, under throttle it gets a small puff of blue smoke. It did not do that until I got it back on changed the oil. Rode up and down the street and it's still the same. Runs great, starts instantly, but still no oil in sight glass and a little blue smoke.

Am I going crazy on the sight glass thing or is there a possible problem there since the oil doesn't show in the glass anymore? And the blue smoke only after the oil change is weird too. Bike has stock updated crank, stock piston, and a ported head with roughly 20hrs on it per hour meter.

[wistech]

Pull the scavenge line and make sure it's flowing oil when the engine spins. If not the scavenge pumps are out and the case is loading up with oil and would cause the smoking The scavenge line sight glasses are handy for just this situation

[who_gives_a6]

Pulled and it is flowing. But should it be in spurts or a continuous flow? It is just shooting in fast spurts, though seems to have pretty good flow overall. Still no flow through the sight glass. I've always put in 1.25qts and did the same this time. It's no big deal to tear down if needbe, just hoping to figure it out without doing so.

As mentioned. No loss of power, starts easy hot or cold, and it's not like a two stroke smoking; just a little under heavy throttle.

[wistech]

Did you test it with the engine running or just cranking. While running it flows enough to empty the engines supply in less than a minute. If its like spurting due to piston pressure in the crankcase you wouldnt get much flow . Do you remember what you gapped the rings to when installing them?

[who_gives_a6]

I tested it when running and got the spurts. Definately not enough pressure to empty the case that quick. Don't recall on the ring gap either as it's been awhile. Hoping that's not the case but would give me a reason to go with a bigger bore size if tearing down.

Would there be any possible issues from riding it for a bit like this as I already did? Still learning when it comes to the two wheeled ones.

[polyesterpig]

If you used gapless rings it might smoke a little. Every time is used Gapless rings the seem to smoke a little. More snap to the motor, but smokes at a stop light. Yep Street plated.

[who_gives_a6]

Thanks for the help Wistech but figured it out. Turned out to be the rear filter screen on the engine. Had some gunk on it that was virtually blocking the flow. Cleaned out and now the oil flow is great through the sight glass and the smoking is nearly gone. Still has a slight amount but is almost gone and seemed to get better as it ran.

I usually only check the filter screen every few changes but guess I will routinely from now on.

[wistech]

Logic would dictate that if the oil inlet is restricted you would back up oil in the frame and the sight glass would be overfilled. Weird. Is your sight glass on the left or right side of the frame? as far as the gapless rings I concur as mine have still have puffed if idled for a while. Leakage is near zero though .

[who_gives_a6]

Sight glass is on the shifter side. No clue on the situation but cleaning off the gunk worked, lol. Could be coincidental.

[wistech]

Hey if it works run with it.