My bike has been parked up for a week, waiting for a new brake caliper to come.

Finally got round to fitting it today, and notice, whilst I’m poking around near the underside of the bike, a small oily patch.

The oil appears to be coming from a small rubber hose, that runs down the back of the engine case, and emerges underneath the rear brake lingage. It has a partner, but that doesn’t appear to be leaking anything.

Any idea what it connects to, and is a tiny bit of oil coming out of it good or bad?

You can just make out the hose running down by the two two bolts to the left of honda logo in this picture:

Engine breather hose perhaps.

Oil pressure builds when engine running, excess pressure and small amounts of oil can escape.
Sometimes a breather filter can be swapped in on some engines. And some performance bikes have a small catch bottle on the end of the hose so the excess pressure from giving it full throttle at the lights or stabbing the NOS button dosen’t vent oil over the back wheel/down the crank case/ down your leg 🙂

The other one might be the battery vent hose.

Got the bike manual or Haynes guide ? should explain it in there.

Check the oil level anyway, most likely nothing to worry about, quite a few bikes vent/leak a tiny amount, just be glad it’s not an old british motorbike, they mostly had an external engine lubrication system using internal oil 🙂 (leaked lots)

Cheers, I think I’ve established it’s attached to the fuel pump.

There’s no mention of it in the manual that I can find, but I don’t have the haynes guide.

The oil level is good, so I’ll guess its the over pressure thing!

Cheers, I think I’ve established it’s attached to the fuel pump

Eh? I’d get someone to double check that you’ve fitted the caliper properly…

Um… They are different issues. One noticed whilst fixing the other.

I’m not hugely mechanically minded, but even I know plumbing brakes into the fuel system is bad! 🙂