Got to wondering about the 610 blow-by venting (may be same on the 630) ... from the head there is a large hose straight to the tubular frame above ... then a thin breather to the airbox. Low down on the centre main tubular frame there is another small pipe vent from engine again into the frame. Now what happens to any blow-by condensate oil ... does it just build up in the sealed frame to go where? Is there very little on these engines? Who knows? I could drill a small hole right at the bottom and see what comes out I guess
The breather hose you're speaking of collects the vaporized oil from the head and gearbox and sends it to the airbox so it can be sucked into the combustion chamber and the hydrocarbons contained within the mixture (that are pretty toxic) can be burnt. Basically it's emissions related stuff, but I wouldn't let it puff freely. Racers use external containers, and I believe the new Euro 4 emissions standards require a separated container. The 610s don't have a whole lot of vapors, I personally don't think it's worth the trouble to remove it and I believe oil doesn't condensate in the frame but in the airbox
I just replaced my piston rings and i seem to be getting alot of vapor coming out of the breather hose if disconnected. Ive only taken it on 4 15 minute break in runs so far. There was also a small amount of oil on the intake valves already. I'm really hoping the rings seated right and that's not why the vapor is coming out. Any input?
Mmh the vapors can seem a lot but the major difference I noticed when my rings were shot was a that a lot of oil condensed into the airbox in a very short time (50 or so kms) and eventually dripped down from the lower airbox intake, so basically check how much oil is there. A little bit of oil is normal (like a few ccs). To be 100% sure you could take the bike to a shop and get your exhaust gasses measured, a high concentration of HC (Hydrocarbons) indicates you are burining oil.
the so-called blow by is noticeable at low engine speeds but must be attenuated almost until it disappears when the number of engine revolutions increases. in this video we see the blow by of a pegaso 650 with an engine in very good condition. give it a try View: https://youtu.be/jqw_mtBkms8
4T pressure and suction waves inside the crankcase each time that piston goes up and down. Best to be in a neutral state with good crankcase breathing. sorting the vapor is the other issue with most machines closed circuit into the airbox or intake path. Some like the x lite machines did go into the backbone and could be recovered when it condensed through hose setups. I remember my old 610 had a plastic breather box up high in the frame that would allow condensate to flow back into the engine.
