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Re: Harley Knucklehead to M20 bottom end

NigP
It does figure, as many of the side-valve bottom ends seem easily converted - its the crankcase stud centers that usually define what you can do.

I was playing with a 16H bottom end and thinking of making a OHIV conversion - like an Aquaplane 100E head I had years ago -
While messing, I realized a BMW1000 barrel and head (i was racing one at the time) could be grafted on, with minimum effort.
Even less machining was needed to fit the 750 BMW cylinder (smaller barrel spigot).
Roughed it out, but never finished it as I became involved in a BMW F2 outfit for Dave Saville and Sabre racing.

I've seen a Porsche Cylinder and head bolted onto a B44/50 (cannot remember which) bottom end - these have the same crankcase/cylinder stud spacing .......


Here's a 16H/Matchless special that's showed in the Warzone speedway book. The 16H bottom end is the same as an OHV Norton Model 18, except the 16H has bigger cams and a domed piston, so ideal for turning into a tuned OHV engine.

 photo Don Francis 16H Matchless special. Fayid 1949_zpstiw7005u.jpg


1945 Model 18 bottom end
 photo DSC_0093_zpsqlrlkuey.jpg

16H bottom end with larger cams.
 photo IMAG1984.jpg

email (option): horror@blueyonder.co.uk

Re: Harley Knucklehead to M20 bottom end

Scroll down on this page for a few other examples http://www.diagnosis2012.co.uk/halfadavidson.html

I am actually thinking of doing this sometime in the future. I think a knucklehead would go better with the look of the girder forks and the rest of the bike. However, they are I think more expensive than shovel cyls and heads, From what I've gathered the three main worries are:
Bolting patterns cylinder-crank cases
Piston hight/stroke/compression ratio
Angle of push rods and push rod tubes

Maybe in 5-10 years or so I'll be posting pictures of my build...

/s

Re: Harley Knucklehead to M20 bottom end

I have a knucklehead engine in pieces if anyone needs any more measurements!

email (option): davmax@ntlworld.com

Re: Harley Knucklehead to M20 bottom end

Hi Ron, The video is on my Facebook page. It came from John Gleeson who lives on the Isle of Man.

email (option): britool51@hotmail.com

Re: Harley Knucklehead to M20 bottom end

On the lever follower Norton engines, only the Exhaust cam is 'Bigger' - i.e. more timing and a tad more lift.

Why to do such things - I think many of us dream of building our own engine, to fulfill a specific task - a MONSTER single, fast SV, etc.
Castings can be expensive to have made and machined, so the logical choice is to use existing components
Mix an Match

I've seen some epic's in the past - one a friend build always blew my mind - 4xHonda 160 top-ends on a welded (ali) crankcase, with an Imp crankshaft (I suppied) and ....... V8 OHC screamer ...
Revved to well over 10K - in the 1970's - all installing I a 250 Rudge chassis ..........!

He did have to take one set of heads off to change the inner spark plugs though.

UTube now has some really awesome stuff from around the world.

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