Engine Oil Vent Hose as an Indication of Over-fill?

Hi all,
When I got my bike, it appeared that it had slightly too much engine oil (3/4 to the max line on dipstick), so I drained a little out to bring it to the mid-point between the min and max lines. But I keep wondering if any damage from overfilling was done. I understand that the clear hose behind the right foot peg is where excess oil would be expelled from the airbox due to over-filling. Mine still has the little plug in the end and I can see no trace of any oil inside the clear hose. Does this mean I can rest easy? Or is it possible that an over-fill could foul the throttle bodies and stepper motor without dumping oil in that hose? I'm a fairly novice wrench, so I'm wondering if I should have it checked by a pro or just forget about it and hope for the best...
Thanks,
Don

Relax. Its all good.

Overfilling will result in the excess being expelled and yes, it does end up in the airbox. Over time there is the risk of fouling the TB's so the butterflies don't close fully. This can be problematic as if the butterflies aren't fully closed after they have been balanced and the TPS has been re-set the ECU will be delivering an inadequate amount of fuel for the amount of air being passed. In turn the stepper will try and govern the engine to target idle by shutting off feed but this can cause an over-correction so the engine will try and stall, the ECU then panics and whacks open the stepper and the revs rise again leading to a high and surging idle.

The thing is that this is something that is cumulative, it won't present as a problem unless you are one of those anally retentive weirdos who at the end of every ride puts their bike up on a stand and adds oil with a pipette until it is *Exactly* at the full mark, (Which is in fact an 'Over full' mark! ). Over a period of some tens of thousands of Km it will gradually present as a problem. The factory recognises this and nowadays recommends that the TB's be removed and cleaned every 10,000Km service. I personally think this is absurd overkill. When I swapped my TB's at close to 70,000kms they were fairly grubby and certainly with the new ones on the bike was noticeably happier and crisper but it had never had any real *Issues* prior to this. I would think that removing them and giving them a damned good seeing to every 50,000 would probably be a good idea but really, worrying yourself silly about the fact that your bike may of been slightly over-filled is un-necessary.

Keep the oil between half way and the 'Add' mark, drain the airbox tube every 10,000km service, ride the snot out of it and stop worrying. Its a GRiSO! You can't kill it with a shitty stick!

Pete

Why hasn't somebody bothered to turn up a few billet dip sticks with the correct markings?

We must all be tared with the same brush as the factory designers, they put up with a 1" sump spacer for 25 years before bothering to make a one piece sump of the correct depth.

Somebody has, but they're not exactly cheap:

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I think it might be worth it to have some confidence in reading the level.

Thanks Pete for your sound advice! When I'm not riding the GRiSO, I'm obsessing about some aspect of its care. I'm very lucky to have an understanding girlfriend who likes bikes almost as much as I do.

I've never had any trouble maintaining proper oil levels with the OEM dipstick. Sometimes we worry for worry's sake I think. It's a Guzzi, stone age technology.