One way reed valve breather...does it really make a difference?

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My 880 race bike has sat in my office for more than 10 years and this winter it has deposited it's first drop of oil on the floor.
 
XTINCT said:
Are you sure that it has oil in it? lol
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:eek:

I lied again, not 2 months to wet sump.
My log book shows that I last ran the bike on Dec1 when I retorqued the head and did some other maintenance.
So it's 4 months later and the oil tank is about 1/2" below the bottom of the stick.
That's only about a quart or less that has leaked thru to the sump in 4 months.
It'll get ridden tomorrow, don't expect any smoke on startup with that wee bit extra in the sump.
And the floor under the bike is clean, no oil spots after a four month sit. Now if the sump was full that might be a different story.

Glen
 
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wornorn ya didn't stick around, for all the details features Kelly George made sure to point out and demo to me after ya split, maybe ya already knew, but 2nd after him grinning about single carbs naysayers also had strong opinion on lack of need/benefit of flapper valve breather having me put cigarette at end of long open breather tube, while starting then rev up some, few hits almost blew cig out but then barely moved smoke - most slightly sucking in from lower pressure w/o any valve at all but the length of the hose. Not saying the rest of us don't benefit by flapper valves just an exception that proves the rule ain't set in stone. hehe I did not have rudeness to tell Kelly his winning flat tracker didn't pull as hard as Ms Peel on similar hi hook up surfaces and didn't wheelie like his pulling those G's. Not that Peel could match it on full boggie top end but pleased to know her pecking order zone not far off. Peel will have vac gauge to see crank pressure and know for sure. Pretty simple to rig up to see then can remove clutter after knowing or leave to enjoy watching.
 
I have used the reed valve breather a few times and it does it's job well. However, lately I have come across the AMR timing case mod to stop wet sumping and that (so far) has done quite well. I have a P11 motor in a Trackmaster frame and the oil level has not dropped in three months. I know that it takes some time for the reed valve to pump a fully wetsumped Norton back to the oil tank so I think both modifications used together would be ideal.
 
André Bourbonnais said:
Looks like I have a 71 bottom with a 72 Combat top. Damn.
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The quality of advice you get will improve greatly if you post photos of what you have. You have been getting a lot of advice on Combat engines that doesn't apply to your circumstance. Such as where the breather is located and whether or not the cases need machining.

Is there a red tag on the head stock that gives a date?
 
worntorn said:
I wonder if it is more effective on pre MK3 Commandos, you know, the ones that leak oil;)
Seriously, the damn thing has never leaked a drop, even after a hard mountain run on a hot day.
I park it in the modern bike part of the shop, along with the 1360 Vincent, also dusty dry.

The rest of the shameful crew straddle
incontinence trays. Some of them could use a reed valve or two.

Glen
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Just a bit off topic, though I would add that I'm going to fit a reed valve to my 850, but, liking Vincents, what is a 1360? Thought they were about 1000 cc.
 
They are 998 cc unless you encounter a speed crazed Australian/ exPat Brit Septuagenarian named Terry Prince. He provides parts to make a 1200, 1272, 1330 or 1360. He also has Cams and heads to make it really fly.

Glen
 
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