I recently changed engine oil of my Apache rtr 160. I used otul 5100 15W50. Later I started experiencing vibrations, a lot of vibrations. I checked on the engine oil. The quantity is reduced to half. No engine oil leak found. Quantity that I poured in was 1ltr. Required quantity is 1ltr. What could be going on?

  • Is your machine blowing any white smoke out of the exhaust? A great way to check is to get in front of some headlights at night and rev the engine. Nov 4, 2015 at 0:12
  • no it is not blowing any smoke.
    – tushar
    Nov 5, 2015 at 19:08
  • What year is the bike and how many miles does it have on the odometer? Nov 5, 2015 at 19:32
  • 2
    Have you checked your airbox where your air filter is located to see if there is oil buildup? Your crankcase pvc is attached to the airbox and when the reed valve in the valve cover doesn't close properly your airbox can fill with oil that gets past it. Nov 5, 2015 at 19:44
  • 1
    The symptom would be oil in your airbox. That's where your airfilter is. Check your airfilter, if it's saturated with oil OR there is a lot of oil buildup in the bottom of your airbox you're PVC system with the reed valve is probably compromised. Check the airbox/airfilter first for oil saturation. Nov 7, 2015 at 17:05

1 Answer 1


You should clean the area around the bottom drain plug, fill the oil back up to capacity, run the bike and check to see if the leak is at the drain plug. The aluminum washer which seals the plug can become "squished" at some point and require replacement. On my car, I replace this washer every time I change the oil, though it does come in the oil filter kit (along with needed o-rings and filter). This is the most logical place for the leak to be occurring. The oil can either be burned or leaked. Since (I assume) you are not seeing voluminous amounts of blue smoke coming out of the tail pipe, you have to assume it is being leaked.

  • There are no drip marks of oil at the place where I park the bike.
    – tushar
    Nov 1, 2015 at 16:56
  • there are pretty much only two places oil can go from an engine. a) leaks b) burned. If it's definitely not burning oil, then looking over closely for slow leaks would be a good idea. Slow leaks may not leave visible drips where the bike is parked.
    – Leliel
    Nov 5, 2015 at 21:37
  • How do i check slow leaks? Thinking of attaching a piece of cloth near the drain plug. Will that be okay?
    – tushar
    Nov 6, 2015 at 16:44

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .