Cilinder angle 3 1/2

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MickeyMoto
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Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Cilinder angle 3 1/2

Post by MickeyMoto »

P&S wrote:My God, what have I done. :o
Really couldn’t immagine to upset you so much! :cry:
But this is the hard truth. :P


Sorry MickeyMoto, I didn' understand you. forgive my english :oops:
"Zero degrees? There is only one, shared, on the crankshaft? The vee will set tdc to be different on both cylinders."
Could you explain it?
Ciao P&S,

I'm glad you understand British humour...

My understanding is that the crankpin holds the connecting rod (big end). On the Morini this is common to both rods. In a parallel twin (ignoring main bearings and crank webs) this would be described as a 360 degree crank, both pistons rise and fall together. On a boxer engine the pistons would be 180 degrees out. So, on a vee twin although the crank pin is common, one piston will be at tdc (PMS?) and the other somewhere else but not tdc or bdc. Not sure how this works on a Ducrapi... probably why a 270 degree parallel twin sounds like a 90 degree vee twin! My brain hurts...
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P&S
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Location: Rome Italy
Location: Roma

Re: Cilinder angle 3 1/2

Post by P&S »

If I understood you are confused by seeing in the drawing the front piston at TDC, and the rear one at BDC with two crankpins.
That is due to the kind of graphic representation on hand drawings of the time.
Different positions are shown in the same drawing.
The maximum run of pistons, one head in a side view with pushrods ( virtual side view because real structure is not orthogonal) , the other one in a front view with valves.
Things are as you always knew.
Hope now you give up your intent. No beards and sandals please, I don't want to be responsible for the birth of the Morini Regular Clerics :lol: :lol: :lol:
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corsaro chris
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Re: Cilinder angle 3 1/2

Post by corsaro chris »

But P&S, you might be responsible for the birth of a new MRC T-shirt?

Good riding, everyone :o :o :o

CC
"I'll use the Morini"
mgelder
Posts: 136
Joined: 18 Jan 2011 14:36
Location: Cambridge

Re: Cilinder angle 3 1/2

Post by mgelder »

P&S wrote:If I understood you are confused by seeing in the drawing the front piston at TDC, and the rear one at BDC with two crankpins.
That is due to the kind of graphic representation on hand drawings of the time.
Different positions are shown in the same drawing.
I think this is what confused me; my training as a draughtsman 40 years ago overwhelmed my relatively recent knowledge of Morini engines :shock:
P&S wrote: Hope now you give up your intent. No beards and sandals please, I don't want to be responsible for the birth of the Morini Regular Clerics
I already have the beard and sandals.

With blessings to all.... :D
Morini stuff on RealClassic.co.uk: http://www.realclassic.co.uk/profiles.html#morini
leos
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Joined: 04 Dec 2014 15:34
Location: Amsterdam The Nether

Re: Cilinder angle 3 1/2

Post by leos »

All Vic Willoughby's interviews were collated into book form
Is this the book: Classic Motorcycle Engines A New Perspective On 20 Outstanding Designs?
harrymuffin
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Joined: 07 Apr 2014 16:06
Location: west midlands

Re: Cilinder angle 3 1/2

Post by harrymuffin »

That could be the one. I have his 'The History of the Racing Motorcycle' but I once rented a from off a chap who collected motorcycle magazines from the year dot, so I was able to read the article from the magazine which I have a photocopy of. I have read other collated articles by him which I have managed to order from public libraries. Is it not possible to inspect the contents?
I have tried uploading the first page of the interview with the bit you probably want to read, but the forum won't load it - to large. If you pm me with your e-mail I will send you the article.
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P&S
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Location: Rome Italy
Location: Roma

Re: Cilinder angle 3 1/2

Post by P&S »

Talking about books, this is the one where Lambertini's engine drawing came from:
"Moto Morini 3 1/2. Il bicilindrico simbolo degli anni Settanta"
leos
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Joined: 04 Dec 2014 15:34
Location: Amsterdam The Nether

Re: Cilinder angle 3 1/2

Post by leos »

Thanks for the article. My ignition builder now understands the strange angle i told him.
mad muller
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Location: liverpool, england

Re: Cilinder angle 3 1/2

Post by mad muller »

i dont understand any of that , and iam glad, now were did i put those longer pushrods!
leos
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Joined: 04 Dec 2014 15:34
Location: Amsterdam The Nether

Re: Cilinder angle 3 1/2

Post by leos »

Any news about the t-shirt???
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