also on my big-bore shadow. a few pictures of our (vincent speet, berni kurschel and myself) design.
ET: Engine (Twin) Breather help please
- Thread starter kerry
- Start date
While Vincent´s elephant is the nicest elephant I have seen I would not want one on my bikes. It is a bit bulkier than the standard cover and there is one hose pointing down. So no way can any minimal oil return or drain into the engine. Where does this hose end - in the air below the engine ?? So that bit of remaining oil will go down the road - just like with the standard timed breather setup !!
With sick engine I mean any leaking seals (dynamo) or worn piston rings so there will be quite some more air to go out any sort of breather system that is not just blow-by from rings. So with a healthy engine you have just some piston ring blow-by air which is minimal and will not lead oil drops up the hose to the reed valve stuck up the hose end to exit into free air.
So yes, Kerry, keep the small elephant and have the valve repositioned at end of hose , could be under dual seat at the back, no oil expected from there at all. Just feel with your hand behind the air exit for judging the small amount of air we are dealing with at all. A small hose will do nicely .
As said, with the timed breather Vincenteers are used to have well oiled rear tyres as the hose runs along the bike very low to rear axle plus one or two pipes that are meant to deflect oily air away from the tyre - and mark their territory at each meeting parking space . . . . So no to timed breather as oil cannot return into the engine once in the hose .
I´d prefer to have the breather hose alternatively connected to a valve spring cap high in the engine and far away from heavy oil mist like in the timing chest - where you really want a lot of oil mist for lubricating cams and followers ! Again, stick the reed valve into the end of breather hose a bit higher level than the valve cap, so a chance for drain-back to engine .
For easing air exit from valve cap it is never wrong to widen the gap made for the rocker in the head like in my photo - for all valves ! . Another plus is more oil mist for upper valve guide AND for valve springs that like lube as they are designed for bodily contact each other - flutter fighting spring resonance effects !!
Vic
With sick engine I mean any leaking seals (dynamo) or worn piston rings so there will be quite some more air to go out any sort of breather system that is not just blow-by from rings. So with a healthy engine you have just some piston ring blow-by air which is minimal and will not lead oil drops up the hose to the reed valve stuck up the hose end to exit into free air.
So yes, Kerry, keep the small elephant and have the valve repositioned at end of hose , could be under dual seat at the back, no oil expected from there at all. Just feel with your hand behind the air exit for judging the small amount of air we are dealing with at all. A small hose will do nicely .
As said, with the timed breather Vincenteers are used to have well oiled rear tyres as the hose runs along the bike very low to rear axle plus one or two pipes that are meant to deflect oily air away from the tyre - and mark their territory at each meeting parking space . . . . So no to timed breather as oil cannot return into the engine once in the hose .
I´d prefer to have the breather hose alternatively connected to a valve spring cap high in the engine and far away from heavy oil mist like in the timing chest - where you really want a lot of oil mist for lubricating cams and followers ! Again, stick the reed valve into the end of breather hose a bit higher level than the valve cap, so a chance for drain-back to engine .
For easing air exit from valve cap it is never wrong to widen the gap made for the rocker in the head like in my photo - for all valves ! . Another plus is more oil mist for upper valve guide AND for valve springs that like lube as they are designed for bodily contact each other - flutter fighting spring resonance effects !!
Vic
Yes it is working well without the big ugly Elephant, no froth, no oil mist, done as Tim recommended, I am very pleased.
Put a 6,1/2" Miller headlamp on last week, Just got to fit original carbs next and bike then is near standard.
Pheasant comes into my workshop about 3 times a day saying 'feed me' so I will not be eating him any day soon !
Put a 6,1/2" Miller headlamp on last week, Just got to fit original carbs next and bike then is near standard.
Pheasant comes into my workshop about 3 times a day saying 'feed me' so I will not be eating him any day soon !
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What am I looking at...is this a breather you made..is it available. I've fought the breather problem for years and never have come up with one that keeps oil off my rear tire. Then too I have a McDouglator and I'm not smart enough to know if it's leaking or not, never could give a definite yes or no, but I'd sure like to try another breather if I ever get the bike to run again.
The breather shown on the engine here looks a lot wider than the one in the photos below...is this breather available or is it posted to make us jealous..sure looks great in the below photos and the one on the bike looks pretty wide.
hello carl, the pictures show the breather and details of our design and production. i´m sold out at the moment, have to go for another batch, seems that it will have to wait till the next winter as i´m just to busy with work. if you wish i can put you on the list and get in touch when it´s ready.
My Shadow, now has just the shown below, I was worried that the bore and slim Elephant would not be enough but all appears to work fine.
The pipe is 14mm outer 9mm inner with a non return valve, no oil comes out the end, maybe it is too small in its body and pipe but seems to work fine. Timed breather has been blanked off.
The pipe is 14mm outer 9mm inner with a non return valve, no oil comes out the end, maybe it is too small in its body and pipe but seems to work fine. Timed breather has been blanked off.
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