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Discussion Starter #1 (Edited)
Any constructive advice is welcome.

>:)>:)>:)So guys the project is underway, I have dived in with very little facts on fitment but my investigations seems close to a good fit .>:)>:)>:)

Here's some facts:
a] base gaskets are the same.
b] conrods are the same.
c] head bolt lengths and diameter are the same.
d] top of the air box is the same.
e] bottom of the air box is different due to throttle body size.
f] SS is single spark plug, monster 1200 is twin spark.
g] Cylinder heads and cams are different.
h] stroke length on 2014 monster is same and bore increases from 96mm to 106mm - cylinders are obviously different.
i] Cylinder head covers are the same.

Purchased 2nd hand from multiple suppliers/sellers: For the ethical record, I have seen evidence of bike accident damage, so nothing stolen.
a] Complete twin spark cylinder heads with cams and valves etc are procured off 2014 monster 1200S.
b] twin spark coils and cords procured off 1200 base.
c] 56mm throttle bodies (SS is 53mm) Means the lower airbox needs altering. Off a 2016 monster 1200S.
d] Monster 1200 cylinders and pistons procured.

Outstanding:
a] Gaskets
b] New piston rings
c] investigate if monster lower air box will fit the SS or simply make the holes bigger.
d] EDIT: Procure inlet manifolds
 

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Wow. This looks like any awesome project. In all honesty, while not quite plug and play, I think that it could be pretty straightforward. Best of luck! Thanks for sharing it here!
 
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I wish you good luck in your quest. Are you confident that the bottom ends can take the extra strain that they will be exposed to, crank shafts, bearings etc.
 

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Discussion Starter #6
I wish you good luck in your quest. Are you confident that the bottom ends can take the extra strain that they will be exposed to, crank shafts, bearings etc.
That's my most worrying point and will only know once done. The big ends are the same but the part numbers are different, it might be the flywheel connection that makes it different, I don't know.
I could have bought a complete engine but we have to jump through hoops of corruption to get such an import cleared, since there are none available in SA. Might require me installing the monster crank later, but time will tell. Good point though.
 

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Discussion Starter #9
@amoslws - You know you've spoilt Ducati's EICMA 2018 reveal don't you? >:) Ducati are going to be so pissed...

Seriously, very keen to see how this works out.
Hoping it works matey. I love the comfort and handling of the SS but I have always felt I am wringing its neck to get somewhere... Hope I am doing the right thing. Feeling nervous but also amped.
 

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That's my most worrying point and will only know once done. The big ends are the same but the part numbers are different, it might be the flywheel connection that makes it different, I don't know.
I could have bought a complete engine but we have to jump through hoops of corruption to get such an import cleared, since there are none available in SA. Might require me installing the monster crank later, but time will tell. Good point though.
The Monster crank won't fit. The 1200 engine uses roller main bearings but the 937 engine has plain bearings for the mains.
 

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I also just noticed that the stroke of 1200 Monster is 67.9mm whereas the SS is 67.5mm. The 0.4mm shouldn't be a big problem but it will mean slightly less than the 13:1 compression and perhaps more importantly a reduced squish. So the hybrid engine will probably be down on power a little from the Monster's 147 bhp. It should still be a lot more than the SS though.
 

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You've got guts, hope it works out.
Agreed. My money's on Amos to pull this off or to determine that it can't be done. That's also a valuable accomplishment; making the journey and returning the bike back to 937cc should not be considered a failure. Wish I could serve as an apprentice to learn.
 

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Discussion Starter #16
The Monster crank won't fit. The 1200 engine uses roller main bearings but the 937 engine has plain bearings for the mains.
We might be considering different year engines, but the 2017 monster bearings and the 2017 SS bearings are the same part number. The conrods are the same part number too. Nr's 15820234A & 11210121A/B/C/D. From 2013 there has been very little mechanical change on the monster, the advancements have been in the electronic frontier and the throttle body.

On the SS there are weirdly 4 options of crank, and the monster has 2 options. Anyway I have been looking into it and the SS crank will be fine. The SS has a lighter crank than the monster so I might lose torque compared to the monster but I should gain top end HP. Frankly the HP is not as important to me when considering my lust for torque. What I expect to happen is the SS will be sluggish at pull off but once the revs are up it will flucking fly. I will be keeping the SS gearbox since I prefer that over the monsters but to settle the bike a little, by that I mean to keep the RPM's down at cruising speed, I will change the sprocket ratio but that will come much later.
 

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Good luck!
 

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We might be considering different year engines, but the 2017 monster bearings and the 2017 SS bearings are the same part number. The conrods are the same part number too. Nr's 15820234A & 11210121A/B/C/D.
No I'm looking at the 2017 parts lists for both bikes. The conrods are the same but show 2 different big end shell tolerances (B&C) for the Monster but 5 tolerances for the SS (A,B,C,D&E) but the big difference is the crankshaft main bearings. The Monster crank is supported on roller bearings while the SS crank is on plain bearings. No matter, if the SS crank is going to work you'll have no problem.
 

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Discussion Starter #19
No I'm looking at the 2017 parts lists for both bikes. The conrods are the same but show 2 different big end shell tolerances (B&C) for the Monster but 5 tolerances for the SS (A,B,C,D&E) but the big difference is the crankshaft main bearings. The Monster crank is supported on roller bearings while the SS crank is on plain bearings. No matter, if the SS crank is going to work you'll have no problem.
You are right though, the top end is reasonably achievable but the crank throw is a concern. Problem is that no one really knows the outcome until its done. I thought about the shape of the pistons and hope the valves will miss the piston. There just isn't sufficient facts out there to make an accurate decision so it's a case of trial and hope no error. My bet there will be a few other guys interested in this, with you @Derek being at the forefront.
 

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Good luck with it Amos. It will be very interesting to see how this turns out.
 
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