The Impossible Shot (You think you're having a bad day?)

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I got one of those for $25 new, and keep my old Android phone just for that purpose.
 
@swooshdave given the amount of time and effort you have put into improving the breathing side of your engine, I was surprised to see your reed breather on the end of a piece of rubber hose.
Surely this is a great opportunity to get the valve close to the engine?
My view of your current setup is:
  1. the hose is acting as a heat insulator - when the exhausted gas hits it, you’ll get mayonnaise as the hot air with it’s air-bound oil hits the colder component.
  2. the give and flex in large diameter rubber hose will negate many of the benefits of using a reed valve. We are trying to get these things buzzing and resonating for them to work at their maximum efficiency, and by putting a big buffer inline where the air can be easily compressed is somewhat defeating the object.

Maybe one of the breather experts like @comnoz and @jseng1 can chime in here?

I wasn’t going to post this, as you get plenty of feedback from others, but this has been on my mind.
 
I've dropped engine pieces/parts that somehow fell/disappeared through incredibly small openings. Similarly, any time you work onboard a boat, all dropped items LEAP toward the water. All this is some sort natural law thing - probably associated with entangled particles or some other such quantum physics thing...;)

OTOH,
I once disassembled a Mopar 340 motor for rebuild and found a Craftsman 9/16" wrench laying in the oil pan. The engine had been running with that for at least a couple of years! It became my "lucky 9/16ths" and it's the first 9/16ths I reach for.
 
Doing an overdue valve clearance job on my buddy's ZX-14, I noticed a dowel missing from the top cover. Searched high and low, magnet, flashlight, etc and nada. I have dropped valve shims before and always recovered them. Seems like a dowel would be harder to hide than a flat shim.The bike had had a check at 500 miles but nothing until 30,000 when the cold engine refused to fire due to 3 exhaust valves losing their seal because of zero clearance, requiring the cams to be r&red twice to get the right number. Rode it up and down the road and it ran perfectly, but the owner was so paranoid about the dowel, he sold the bike. I told him the shop likely lost it when they popped the cover at 500 miles, but he couldn't get it out of his mind. This was several years ago.

Recently, he saw the bike parked at a local pizza joint and went in to talk to the new owner to see if anything happened. Nothing more than 17,000 additional miles and smiles. So if I dropped it, it either hit the deck and rolled to parts unknown or lodged itself somewhere it could do no harm. Both those scenarios seem much less likely than my original suspicion, IMO.
 
MexicoMike said:
OTOH,
I once disassembled a Mopar 340 motor for rebuild and found a Craftsman 9/16" wrench laying in the oil pan. The engine had been running with that for at least a couple of years! It became my "lucky 9/16ths" and it's the first 9/16ths I reach for.
Click to expand...

A 9/16 is a heavy wrench. It’s wasnt going anywhere.
 
gtiller said:
@swooshdave given the amount of time and effort you have put into improving the breathing side of your engine, I was surprised to see your reed breather on the end of a piece of rubber hose.
Surely this is a great opportunity to get the valve close to the engine?
My view of your current setup is:
  1. the hose is acting as a heat insulator - when the exhausted gas hits it, you’ll get mayonnaise as the hot air with it’s air-bound oil hits the colder component.
  2. the give and flex in large diameter rubber hose will negate many of the benefits of using a reed valve. We are trying to get these things buzzing and resonating for them to work at their maximum efficiency, and by putting a big buffer inline where the air can be easily compressed is somewhat defeating the object.

Maybe one of the breather experts like @comnoz and @jseng1 can chime in here?

I wasn’t going to post this, as you get plenty of feedback from others, but this has been on my mind.
Click to expand...

In theory, there might be some slight gains to moving the breather a little closer but I live in a practical world where that particular valve doesn’t fit nicely at the back of the engine.

That is a really thick hose and won’t collapse.

I’m not sure what you mean about the condensation, the air inside the engine starts out cold and as it warms up so will everything around it. It’s not like the valve is sub-freezing and there’s tons of humidity waiting to condense.

Some people have put the reed valve up by the oil tank, my goal was to get it as close to the engine as I could.
 
I’m aware air comes out of the breather, so no concerns about it collapsing.
I was just thinking that with rubber hose between crankcase and valve, it will act as a damper that will stop the valve resonating to the extent we want it to.

I know you have limited options with a combat (I have one too in one of our project bikes) but if you didn’t want to pay out for one of Jim’s case mounted breathers, surely it would have been an option to make up an adapter plate that allows you to fit the XS650 valve in lieu of the froth tower’s placement?

When we first got the Dommie, the previous owner had fitted a plastic PCV at the end of the breather line - of course it had failed (I think they last about five minutes) I temporarily replaced it with the XS650 valve like you have there, but I did find that hot gas hitting a cold valve would produce mayonnaise and it would make it sticky.
I later swapped it for one of Jim’s sump plug valves.
 
You sure the mayonnaise was from the breather being cold and not the engine oil being cold?

I don’t think the water could condense and blend with the oil just by hitting the breather.
 
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Just my observation.
I’m sure I’m overthinking your scenario and there’s no problem
 
gtiller said:
Just my observation.
I’m sure I’m overthinking your scenario and there’s no problem
Click to expand...

I appreciate the thought. I did explore a rear case option using the Triumph bits. Gave that to a friend to play with. Headed over there now. If he’s gotten somewhere with it I still have time to swap it out. But I need to focus on more crucial things right now like getting the head on and making sure valves don’t hit. The incremental benefit of moving the breather is a lower priority.

Plus once it’s in Proddy spec again it won’t be the go to bike when it’s cold so no mayonnaise. :D
 
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