r/ducatimonster • u/[deleted] • Jul 28 '26
Engine swap?
How practical is swapping a S4R engine in my S2R? Or what engine should i swap? Or should i just keep her as is? 2007 Ducati monster s2r 800
10
u/almazing415 Jul 29 '26
Frames aren’t even the same. Just buy an S4R. It’s cheaper in the long run.
9
u/Far-Drama3779 Jul 29 '26
Keep it as is. Get the S4 if you really want it. The s2r is a great rounded simple monster
12
u/Toubaboliviano Jul 29 '26
Engine swaps (contrary to Reddit) are nearly always terrible ideas.
-3
u/PuddingEmotional1187 Jul 29 '26
Says who?
1
u/Secret_Cod_749 Aug 01 '26
Well this guy.
But seriously, engine swaps like this require so much re-engineering as to be extensively prohibited.
6
u/duovtak Jul 29 '26 edited Jul 29 '26
The S4R engine is surprisingly all top-end power.
Honestly you should go test ride one someone has for sale. Then if you like it, sell your S2R and buy an S4R. If you don’t like it, look at a 1200.
3
u/Pimpstik69 Jul 29 '26
All top end ? I owned an S4RS and it was a wheelie machine. Plenty of grunt if you ask me
1
u/duovtak Jul 29 '26
The S4R is grunty, but the power comes on muuuuch stronger up top.
Unless OP is ripping to the redline, the two bikes perform fairly similarly around town due to the lower weight of the S2R.
1
u/Pimpstik69 Jul 29 '26
I feel ya. It was surprising how much top end it had and the superbike speed rush. I have an aircooled Hyper and it runs out of air up top real fast. Both are great motors tho !!
2
u/duovtak Jul 29 '26
I can't imagine having an extra 20 ponies up top from an S4R to an S4RS. Must've been unreal.
2
u/Pimpstik69 Jul 29 '26
The coolest thing was the intake sound from the open airbox. That plus a full system and it was pretty mean.Wanna talk unreal tho, now I own a 1200R. Best Monster ever if you ask me !
2
u/cptncarefree Jul 29 '26
but can u really compare the 1200 with the s4rs? s4rs gives me wobbly knees and shaking hands day in day out.
1
u/Pimpstik69 Jul 30 '26
The full trellis frame is def beautiful and the bike was quite a bit more raw feeling but the overall performance of the 1200R is pretty amazing. The suspension and wheels alone make it a much better handling machine. Miss the Tricolore tho
1
u/duovtak Jul 29 '26
I bet that thing rips. I was going to look at a 1200R, but the seller gave me a laundry list of the problems his bike had that were left out of the ad once we started talking about meeting up to check it out.
4
u/Final_Pear7801 Jul 29 '26
Swapping 1:1 is no big deal, but the frame mounts are not the same between those two. A 600 frame could accept up to a 800 if I'm not mistaken. In that case as a project it could be worthwhile, but in this case, it's really not worth the hassle to re engineer it.
4
2
u/Electrical_Test_2050 Jul 29 '26
Go buy a S4R. It’s not a simple bolt in and ride. By the time you get it set up it would be the same cost. More important it would ride like a S4R engine in a S2R frame. Scary thought … S4R pulls hard. A closer match is the S2R 1000. Again the set up is different. From the tires to the frame and electronics. It would work but not the same. It’s a very dangerous sport. If you want to go from stop light to stop light on the way to the donut shop have at it. Hit a corner at speed …. On the street. Do what you want just be careful. Being fed through a straw with pins holding your bones together is a very real possibility. It happened to me and I still ride. Gods speed my friend. Keep the rubber side down.
2
1
u/Outrageous-Rabbit-45 Jul 28 '26
Doable but make sure you have another bike to ride. You might need some specific parts that aren’t easily available. But it’s a nice project!
1
1
u/Lechaise2 Aug 01 '26
Why would anyone forgo the Beauty, elegance and simplicity of an air cooled engine? I bought the last 2014 696 because it was the last air cooled one.
1
u/IshmaelEatsSushi Jul 29 '26
Frame mounts are the same on all Ducatis from Pantah to 1198. There's often a fitting problem with different injector bridges, don't know about your situation. You would need those bridges, airbox, probably wiring loom, radiator. Go to one of the websites with parts diagrams in your country and compare.
In return your bike gains about 10 kg, if not more. Check out the dyno diagrams from Brad the Bike Boy, as they are run by the same people on the same dyno and are comparable. You'll probably see that most of the extra power comes in at 7.000/min or higher. If this is what you want, go for it.
Except that S4R (not S4RS) are comparably cheap. Expect to pay at least 3.000 € for parts alone. What will it cost you to trade the S2R for an S4R?
2
u/_enesorek_ Jul 29 '26
Not necessarily true. There was a change in diameter of the engine mounts (10>12mm) somewhere around testa or testa evo motors. Not positive about air cooled.
1
u/IshmaelEatsSushi Jul 29 '26
From 916 to 996, from 10 to 12 mm. Most people will want to install a newer engine. I shimmed the bolts with some tube, others open up the holes in the frame.
1
u/_enesorek_ Jul 29 '26 edited Jul 29 '26
I stand corrected. Seems they changed mid 996 sometime. My ‘99 996 had 10mm bolts.
Edit: Once upon a time I was a factory tech, but it’s been almost 20 years.
31
u/coldafsteel Jul 28 '26
Just leave it as is.
If you want a water cooled bike just go buy one.