OH Oh No TS vent in Peel crankcases

Hobot · Apr 21, 2015

Stumbled on another situation that implies hobot shouldn't be allowed around machinery, custom or otherwise. My plan was to draw blow by pressure off the convenient old TS case magneto-points area but can not see any holes connecting to the crankcase volume. I'd think there is a small oil hole down low hidden behind oil pump but don't know if that's enough vent or if it would just fill TS case up to be sucked out exhaust extractor to fog worse than the chemtrail sprayers. Only thing I know to do at present is completely undo what Canaga spent so much care assembly on to make vent holes, ugh. Open to less tedious rescue remedies - keeping in mind I want active evacuation besides a passive reed check valve. Been pensive world crisis-collapse would hit before I got any pay back from Peel ordeal.

lcrken · Apr 21, 2015

That's because you have Maney cases, and they have a port at the bottom rear for the early style breather. In your cases it's blocked off by a blanking plate held on with two screws. I've forgotten what year 750 used that rear breather, but if you can find one of them, you can bolt it on the cases. If not, you can look at Jim Comstocks breather assembly that replaces the sump plug. Other than that, you'd have to drill and tap the back of the timing side where the stock 850s have their breather tube. All you'd have to do is remove the timing side cover so you could drill and tap without getting chips inside, then replace it.

Ken

Hobot · Apr 21, 2015

I see the low down crank case blanking plate that I detest for fouling gearbox removal w/o moving engine with bulky Combat baffle. Only crankcase connection to TS volume i see is the drain hole exit near top of TS case for head oil down cylinder drain. Peel is intened to blast though-over stuff [rock, roots, drop off edges, logs, deer] that would hi center street bikes so anything under neath would get wiped off. Will have to put some oil in rocker and see where it leaks out TS area then whip up some triple path 'compact' tubing gizmo with JBW copper and clear tube incorporating my wet sump level setter/excess drainer - so exhaust can suck like crazy from TS volume and any oil sucked with it will fall bottom to drain back to cased to be pumped to sealed frame tank. If I put a reed valve down low it might prevent the flooded TS area draining. I sure don't want to break your sealing and sincere blessings of assembling or leave smoking trails into the sunset.

lcrken · Apr 21, 2015

I think I must have mis-read your first post. I thought you were asking about a breather outlet. In fact your cases have both the early 750 design port I mentioned, and an 850 style port in the timing side case. What you are really worrying about (I think) is a connection between the crankcase area and the timing chest area. In that case, your cases have a large hole for that purpose in the timing side case wall. You can see it in this picture just behind the camshaft sprocket

and in this picture, partly obscured by the end of the camshaft.

Best picture showing it probably this one

Ken

Hobot · Apr 21, 2015

Alrighty Ken I'm relieved to see the 1/2"ish hole tucked in behind cam chain sprocket area, whew, as that' means less JBW to be ashamed of. I can stick with plan A tubage for a change.

billet · Apr 23, 2015

Ken, what kind of cylinder is it?
To me it looks like a original cast iron cylinder that is milled where the through bolt is.
And what kind of through bolt is it?
That Picture made me curious.

Sten

lcrken · Apr 23, 2015

billet said:
Ken, what kind of cylinder is it?
To me it looks like a original cast iron cylinder that is milled where the through bolt is.
And what kind of through bolt is it?
That Picture made me curious.

Sten

It's a Steve Maney alloy 920 cylinder with Swain coating in black. Through bolts are normal 3/8" socket head cap screws.

Ken

billet · Apr 23, 2015

Ok, got it.
I was cheated by the paint

Sten

bill · Apr 23, 2015

the best thing you can do is to use the hole where the blanking plate is with the reed breather that jim supplys for the 72-73 750 cases.

lcrken said:
Ken

Hobot · Apr 23, 2015

the best thing you can do is to use the hole where the blanking plate is with the reed breather that jim supplys for the 72-73 750 cases.

Ok bill thanx for fleshing this out for me as was confused on the variations and do need a flapper in case low rpm with drag cam pulses pressure into cases rather than sucks like naturally inspired engines. I'm resisting extra mass and normal routes in Peel so thinking of cork ball in a vertical run of clear tubing with a pin stuck through to keep ball trapped and not plugging exit tube. Dang it might even whistle at times.

Sten I only wish it was paint and not the over $old Swain Black Body Emissions Coating that comnoz showed hindered cooling somewhat. My heart dropped on 1st surprise sight but Peel's an outlaw so why not a black heart.

Fast Eddie · Apr 24, 2015

Excuse my ignorance here guys, but where is the oil drain hole (to drain timing chest oil back to crank case)?

SteveA · Apr 24, 2015

Fast Eddie said:
Excuse my ignorance here guys, but where is the oil drain hole (to drain timing chest oil back to crank case)?

Maney cases clearly evolve like any other product.

Mine came with two 'breather vents' to the timing chest, not the single one visible on Hobot's cases. Both of these are now plugged and Jim's breather is fitted to the rear of the crankcases (doesn't whistle but it can whine!).

I drilled my own oild return hole, Steve does not do it, but nor does he use Jim's breathers. I positioned the oild return for a vertical engine mounting frame a la Atlas, so is actually above the oil pump no below as Jim recommends for a Commando.

Fast Eddie · Apr 24, 2015

I'm guessing Mr Maney's logic is along the lines of: "less holes = more material = stronger cases"?

So, assuming the cases are for use on a Commando with a titled engine, it looks like the hole behind the cam sprocket is for breathing and oil return, as it looks like it is on approx the same centre line as the standard oil drain hole would be.

If that's right... Hobot might want to re-think blocking it off!

Does this mean that Steve sells different cases depending on whether they'll be tilted or vertical?

SteveA · Apr 24, 2015

Fast Eddie said:
I'm guessing Mr Maney's logic is along the lines of: "less holes = more material = stronger cases"?

Does this mean that Steve sells different cases depending on whether they'll be tilted or vertical?

They are pretty damn thick.... those wholes aren't going to make any difference....

And no, I asked him about tilted or not....the same...

Hobot · Apr 24, 2015

hobot is not following comnoz reed valve camp, more Kelly George's open to ambient, so wants Peel's TS volume to be freely connected to the crankcase to dilute the piston decent pulses and act as oil mist settler so not smoking out the exhaust sucker. Maney cases breath and set oil level adequately so not going to drill more holes and risk swarf in Ken's clean assembly. Peel's over size alternator fits behind barrels and would foul reed device on TS flat. Everything about Peel has to do with the wonder of Tri-links to point don't need to slow up like race bikes on paved corners so even leaving sports bike a shift behind after a single turn is too boring secure nil adrenalin hits so its raw off road and parking lot stunts I'm more interested in so nothing can stick on engine/frame area that could be hurt on rolling across head size rocks, stumps etc as common event through brush/vines, tall grass and deeper water crossings. Warning: Do Not Try to Follow my Peel's paths as its crazy making.

Fast Eddie · Apr 25, 2015

SteveA said:
Fast Eddie said:

I'm guessing Mr Maney's logic is along the lines of: "less holes = more material = stronger cases"?

Does this mean that Steve sells different cases depending on whether they'll be tilted or vertical?

Click to expand...

They are pretty damn thick.... those wholes aren't going to make any difference....

And no, I asked him about tilted or not....the same...

The more I look at these pics and think about it, the more I am of a mind that the higher oil level is a good thing, yes it might froth etc, but at least all those moving parts are bathing in nice oil...

Hobot · Apr 25, 2015

Maney rev's his incidental 920 cases to 7200 + some in a pinch and not known for blowing oid seals so agree no big deal if slightly higher oil level than comnoz hole below oil pump. Peel can hold a gallon of oil in most the frame tubeage area so TS oil fill windage may help cool the motor some. I think with 2-1 pulses combined that low rpm will still suck more than burp back into TS volume so really don't thinks i'll need a flapper reed or snorkel ball check valve. I had none in past Peel plumbed this way and never could get slightest hint of oil mist even by cotton Q-tip swab even after the horrendous over rev event that sent oil out every bouncing stretching fastener hole let along seams that turned into curling lips like wave breaking on a beach.

Jeandr · Apr 25, 2015

Fast Eddie said:
The more I look at these pics and think about it, the more I am of a mind that the higher oil level is a good thing, yes it might froth etc, but at least all those moving parts are bathing in nice oil...

I think Jim is right about putting the oil return hole low. Oil that has the constitancy (sp??) of mayonaise will not drain through a tiny hole, less oil means less chance of that happening. He did mention that the oil temperature was higher with the return hole high and lower with the hole drilled low.

I remember a story about some British car that would burn up engines, when the factory found out the problem was caused by an oil level that was too high and it was being whipped to a froth by the spinning crank, the solution was simple, come out with oil level gauges with a lower mark for full. Sometimes the old saying "if some is good, then more is better" does not apply.

Jean