I've got a persistent oil leak on my R1 engine. It doesn't lose any when stationary. Nor does it seem to lose any when driving round town. On a dual carriage way, however, it isn't long before the oil light comes on.

Now the R1 oil level sensor is a bit sensitive and comes on when the oil level is in the middle of the sight glass, so I know that the engine isn't running short, but I have to top it on every long journey.

I thought the leak was from the generator cover, which is at the back of the engine. I've replaced this with a known good cover but the leak is no better. There is no oil coming out of the breather at all and the top of the engine is dry.

How do I track down the source of the leak?

Not sure what year motor you have but on mine (5vy) there is a water pump drain that goes through the bottom of the sump.

There are 2 o-rings which leaked slightly on mine. Didn't loose much though and was fairly obvious once underneath where it was coming from.

I had a leak from the clutch actuator, there is a rubber seal around the rod that can leak. Not a problem when stood still but enough of an oil leak during a run to make a mess of that side of the engine.

Worth a look

- Paul