Best thread(s) for the M750 to 900/900SS/1100 etc swap

[Rudemouthsky]

Hello.

I'm wondering if you folks could point me towards the best and most helpful threads for an engine swap project. I would like to upgrade the motor in my M750 this winter and I would like to go with the setup that has the *least* amount of potential gremlins. If I could find a step by step guide that included ALL of the necessary parts I would need upfront that would be fantastic. I'm assuming the upgrade to the 900 of the same vintage is the most problem free and contains the most compatible parts.

I have a long time veteran tech of japanese and British bikes who is a close friend of the family assisting me with this project and around a $2000 budget.

Also, I'm going to be riding the M750 from McAllen, TX to Puntarenas, Costa Rica before starting the work, that trip is happening in Dec, I'm sure some of you may be curious to see how a baby Monster performs on such a trip so I will document it extensively.

Viva la salud!

[Travman]

If it as me, I'd try upgrading the 750 with 695 heads and high compression pistons. They talk about it in this thread.

http://www.ducatimonsterforum.org/index.php?topic=59597.0

Here is a recent thread by He-man that may be relavant.  He put a 1100 into his S2R1000.

http://www.ducatimonsterforum.org/index.php?topic=59229.0

[Rudemouthsky]

Thanks. From what I've gleaned so far, I've pretty much determined it's not worth the expense and effort to try and work with the 750 motor. A 900 with FCR's is pretty much the route I'm leaning towards. It seems this is a pretty common endeavor among 750 owners. I really love my bike and have a lot emotionally invested in her, and don't mind at all going this direction. The only thing I HAVE to keep is the Road Racing exhaust, I'm fairly certain it will bolt right up to an M900 motor but if not I will find an exhaust shop to help me make it work one way or another. That exhaust is my pride and joy.

An M900 with FCR's will be enough power to keep me smiling for quite awhile.

[ducpainter]

Thanks. From what I've gleaned so far, I've pretty much determined it's not worth the expense and effort to try and work with the 750 motor. A 900 with FCR's is pretty much the route I'm leaning towards. It seems this is a pretty common endeavor among 750 owners. I really love my bike and have a lot emotionally invested in her, and don't mind at all going this direction. The only thing I HAVE to keep is the Road Racing exhaust, I'm fairly certain it will bolt right up to an M900 motor but if not I will find an exhaust shop to help me make it work one way or another. That exhaust is my pride and joy.

An M900 with FCR's will be enough power to keep me smiling for quite awhile.

The header pipes for a 750 are different due to the difference in deck height.

[Rudemouthsky]

Yeah I've read that. I also saw (somewhere) that someone was able to fit the RR exhaust that was on an M900 onto a M600. So I wonder if, even if the stock headers don't interchange, if the RR exhaust has enough flexibility to go both ways.

[carbmon]

FWIW many years ago I installed the RR exhaust made for a 900 on my 750.  Found it was necessary to cut a short section out of the H (front) cylinder header pipe to let it fit and get the cans to 'hang' right (as you know, a single long bolt thru the case supports the pair of cans and they can pivot on that bolt a bit).  Sorry I didn't document the details but I distinctly recall the cut-out section was in a straight, not in a bend, and was longer than the difference in the deck-height between the 750 and 900     (yes, you read that right).

I did not have to modify the V (rear) cylinder pipe.

So, IMHO, going from long-stroke to short-stroke applications with the RR system requires a cut/re-weld, I suspect going the other way you'll find the need to locate a short bit of correct SS tube and insert/weld that to let it fit.  Not insurmountable but don't be too surprised if that's what you find when you get to that point in your project.

I loved the look of the RR system, but it was just too darned loud for me so it sat on a shelf in the workshop for almost a decade 'till I sold it on this forum last year.

Have fun with your project!

[pitbull]

Thanks. From what I've gleaned so far, I've pretty much determined it's not worth the expense and effort to try and work with the 750 motor. A 900 with FCR's is pretty much the route I'm leaning towards. It seems this is a pretty common endeavor among 750 owners. I really love my bike and have a lot emotionally invested in her, and don't mind at all going this direction. The only thing I HAVE to keep is the Road Racing exhaust, I'm fairly certain it will bolt right up to an M900 motor but if not I will find an exhaust shop to help me make it work one way or another. That exhaust is my pride and joy.

An M900 with FCR's will be enough power to keep me smiling for quite awhile.

I've got the RR exhaust on my 01 900 and it wasn't exactly a straight bolt on for me. I had to take the front header pipe and get it bent
about a half inch or so to scrunch it in a little so the bolt would go through the engine to hold the exhaust on.

After a year, I finally pulled the RR off yesterday and put my old micron CF pipes back on. I really, really love the RR exhaust, but it's just too loud for me. I put some cheap, ebay baffles in, which quieted it a touch, but still too loud.

[bigiain]

If it as me, I'd try upgrading the 750 with 695 heads and high compression pistons.

That depends a bit of how comfortable you are pulling motors down and reassembling them.

I recently did the 900 motor swap into my '99 M750 - I bought a '98 900 motor complete with carbs and exhaust headers, and it was literally a Saturday afternoons job to swap motors. Everything was just bolt-on with two minor exceptions, the front sprocket on the 900 motor was the wierd "half shouldered" type so it needed a bit of shimming to align the chain, and the 900 motor I got had the older two-phase alternator so I had to make up some adapter cable to plug just 2 phases into my 3 phase reg/rect.

If you're not 100% comfortable assembling motors, and straight swap is a good option.

Rudemouthsky - consider trying to find a carbed 900 motor complete with carbs/inlet manifold/exhaust headers(/ and pipes if you don't still have you original ones), if you get lucky like I did, you'll get all those extra bits for pretty much the same money as they ask just for the motor originally. That way you could do the motor swap from rideable 750 to rideable 900 in a weekend, then deal with the other things like the RR exhaust and flatslides at your leisure. (I'm assuming "winter in Texas" doesn't mean "I'ver got 8 months holed up in my basement waiting for the snow and ice to melt so I can ride again so I may as well strip my bike down to individual pieces while I wait"?)

big

[Rudemouthsky]

Kinda makes me wonder if RR even made 2 separate exhausts. I've seen people claim they were "only made" for one or the other, and the few times they pop up it's usually 50/50 to the 900/750. Hrrm. When that company disbanded they didn't leave a clue as to what became of their engineers, what they went on to do. It's really bizarre that nobody knows the ex owners/employees and what they're up to these days. Another reason I love the exhaust.

That depends a bit of how comfortable you are pulling motors down and reassembling them.

I recently did the 900 motor swap into my '99 M750 - I bought a '98 900 motor complete with carbs and exhaust headers, and it was literally a Saturday afternoons job to swap motors. Everything was just bolt-on with two minor exceptions, the front sprocket on the 900 motor was the wierd "half shouldered" type so it needed a bit of shimming to align the chain, and the 900 motor I got had the older two-phase alternator so I had to make up some adapter cable to plug just 2 phases into my 3 phase reg/rect.

If you're not 100% comfortable assembling motors, and straight swap is a good option.

Rudemouthsky - consider trying to find a carbed 900 motor complete with carbs/inlet manifold/exhaust headers(/ and pipes if you don't still have you original ones), if you get lucky like I did, you'll get all those extra bits for pretty much the same money as they ask just for the motor originally. That way you could do the motor swap from rideable 750 to rideable 900 in a weekend, then deal with the other things like the RR exhaust and flatslides at your leisure. (I'm assuming "winter in Texas" doesn't mean "I'ver got 8 months holed up in my basement waiting for the snow and ice to melt so I can ride again so I may as well strip my bike down to individual pieces while I wait"?)

big

Yes...that's what I like to hear, thanks. . Are you saying that most/all of your hardware was compatible as well?? sounds too easy...

[hnracing]

To swap from 600/750 carb to 900 carb is a no brainer.
Just do it.
Try to source an 900 carb engine with the true 900 heads V2 heads not the M900 carb engine that came with the 750 head marked W2.
More info : http://www.bikeboy.org/900equal.html
Keihin FCR 41 as carb
Ignitech TCIP4 as ignition

What happens then is that you will start looking for the next improvment so
900 carb --> 900ie engine --> 1000DS engine --> 1100 engine
And then you will start to tune it.

/Henrik
Monster 600 -96 that have been upgraded in that manner so now it runs a fully blown 2V 1100

[bigiain]

Yes...that's what I like to hear, thanks. . Are you saying that most/all of your hardware was compatible as well?? sounds too easy...

Yep. I'm pretty sure I would have gotten away without buying the carbs for the 900 too, but once I asked for the inlet/exhaust manifolds to be included, the carbs came "free". Rejetting the 750 carbs would have worked OK, but easier for me to use the 900 ones (besides which, my 750 carbs were almost 200k miles old, and needed another new set of emulsion tubes…)

Everything else (apart from the minor front sprocket and alternator wiring already mentioned) is 100% as delivered on the 750 - electricals (coils/ignition boxes/starter wiring), fuel system (pump/filter/hoses), throttle and choke cables, airbox - I didn't need to change anything. Apart from the 4 1/2" rear wheel, my bike is exactly like a 1999 M900 as delivered localls.

One thing I just thought of though - here in Australia all the 750s came with oil coolers and twin front disks. I vaguely recall some US delivered bikes didn't have them - so maybe you'll need an oil cooler/hoses/mounts for the 900 motor (mine came with it, so I've got the one from my 750 as a spare), and you'd have to make your own decision about whether you'd ride a 900 motored Monster with only a single front disk (I probably would, but I'd draw the line at advising anybody else whether they should or not).

[beardo]

What happens then is that you will start looking for the next improvment so
900 carb --> 900ie engine --> 1000DS engine --> 1100 engine
And then you will start to tune it.

/Henrik
Monster 600 -96 that have been upgraded in that manner so now it runs a fully blown 2V 1100

Another new guy here. So you're saying an 1100 will bolt into the frames? If so, then game on!

[Howie]

Another new guy here. So you're saying an 1100 will bolt into the frames? If so, then game on!

Depends.  At some point the engine mounting bolts went from 10mm. to 12, 2001 maybe?  The frame can be made to accommodate the larger bolts.

[He Man]

i swapped from an DS1000 to an M1100EVO motor for about $2500bucks. but dont forget you have a DSS bike, so a 1100 motor is out of the question for you. and i would avoid all DS1000 motors due to the valve guide issues.

900 is the way to go since they are a dime a dozen, but in all hoensty, unless you HAVE to do it, its almost not worth the headache of selling and buying a newer model. You ahve more fun with$2000 in suspension parts than you do in engine mods.

throw in AK20 GP kit for $1200 and a penske triple rear for $800, and $100 clip ons and the bike feels brand new.

[Howie]

i swapped from an DS1000 to an M1100EVO motor for about $2500bucks. but dont forget you have a DSS bike, so a 1100 motor is out of the question for you. and i would avoid all DS1000 motors due to the valve guide issues.

900 is the way to go since they are a dime a dozen, but in all hoensty, unless you HAVE to do it, its almost not worth the headache of selling and buying a newer model. You ahve more fun with$2000 in suspension parts than you do in engine mods.

throw in AK20 GP kit for $1200 and a penske triple rear for $800, and $100 clip ons and the bike feels brand new.

Forgot about that.