P11 Oil Hose Routing

elefantrider

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Anyone know the correct routing of the hose coming off the top of the oil tank?
The one which spills oil when the bike is a bit wetsumped.
I cannot find the routing pictured in any of the diagrams.
 
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Is it a breather pipe? I think most were routed beneath the rear mudguard (fender) to exit near the tail light. Check the photo in Roy Bacon's 'Norton Twin Restoration' p150. Tight squeeze but comes with the territory on these :)
 

p400

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My P11 always had a little drool coming out of this vent , not much, maybe 10cc every ride.
To get past the rear frame cross member i used a piece of copper tubing, maybe 2" to go under the cross member with hose on either side.
Then ran down the right frame tube to a shop fabbed catch bottle that could be emptied.
20150925_OilCatch1.jpg
 

p400

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Yes it can be routed out the tail like OEM, but it was a mess for me.
And my engine was fresh rebuild.
 

p400

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I used clear clear vinyl tubing from Lowes.
Fastened a plastic pill bottle lid to the bracket and this left the pill bottle free to twist on/off as needed.
could have painted the bracket black, but never did.
 
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Mine T's into my breather setup, which is a bit odd. I have two 3/8ths hose barb exits from a plate covering the magneto hole. One goes to atmosphere via 3/8ths hose at the lip of the rear fender after going up to the vent being discussed. The other has a power brake check valve setup on it. Also have the intake valve cover vented to the rear fender. I run a Combat (2S) cam and it doesn't support a timed breather, so I shade tree engineered what I'm using now 30 years ago.

And where do P11 restoration builders run the other oil tank vent to? I'm not a restoration builder. I'm a tuner and tinkerer. My other vent goes into a Yellow plastic PlayDoh container with a hole in the lid. It just hangs there behind the transmission. It does get a little oil in it, and it's easy to empty.

I haven't spent a lot of time with the oil tank vents, but the vent pointing toward the rear is a PITA to plumb with 3/8ths hose. I used thin 3/8ths inch vacuum hose, but it still gets smashed down, since I'm lazily going over the flat stock crossmember oil tank mount and then under the frame above the battery box. Maybe someday I'll bend some brake line and do a better job.
 
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elefantrider

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I currently have it routed to the tip of the rear fender, along frame then the fender seam.
My other bike has it going straight down next to the swingarm.
This is probably how it came from the factory but it tends to oil up the swingarm and rear wheel.
 

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