engine transplant options

750pheonix · Post by **750pheonix** » Tue Jul 11, 2006 11:31 am

Hi all, I realise this is a subject few people will have much knowledge on but what are the possibilities for engine substitutes?

the engine that came with my bike it in a bad way internally, it was standing in it's own oil for years...

So rather than face a pretty huge bill (estimated at around £2000.00) for a complete engine rejuvenation... i thought about buying a low milage alternative and mounting that instead.

I haven't decided yet which course to follow but i think the more alternatives i have to choose from the better.

I don't consider myself a ducati purist by any stretch of the imagination so all suggestions are welcome

delagem · Post by **delagem** » Tue Jul 11, 2006 1:09 pm

Hi Phoenix, can you elaborate further on why you feel the current engine needs to come out?

I mean, low compression could be as simple as new rings, a knock in the bottom end, or a gaping hole in the case, on the other hand; most problems will be able to be fixed cheaper than the cost of a new motor plus shipping.

For the record, I'm not a purist either, I looked into putting a Monster motor in my Paso. Not difficult, but there's going to be a lot of details to sort out. Details = money*time!

750pheonix · Post by **750pheonix** » Tue Jul 11, 2006 5:47 pm

ok, got back home... the engine was really oxidized before i dropped it off for a full strip. So the casing will need blasting and repainting for a start.

techincal rundown

lots and lots of seized bolts/nuts
pulley bearing corroded
engine 30% leakdown on front cylinder
35% on the rear
expecting rusted and pitted valves+ seats
piston rings scrap
bush fell out of con rod...
clutch and slave piston in poor condition

basically with the work done so far to get it into bits i am looking at £500 before i start to repair anything.

the estimate for parts andtimecomes to a minimum of 2000.00 or 3000.00 with gas flow and race cams etc...

compared to this a second hand engine in fair condition with loom and ecu would be almost reasonable

Post by **paso750** » Wed Jul 12, 2006 10:23 am

I`ve never done an engine transplant, but if I remember correctly if you use a newer 750 or 900 engine the swingarm mount needs to be machined as on newer engine it`s larger and I think somewhere on the front (the cylinder?!) a hole needs to be enlarged a bit. I suppose this is the front engine mount.

However there`s someone here using a Monster engine.

If you get a new/used engine and start tuning it it will cost for sure more than rebuilding yours and while you`re at it modify it.
At least that is my experience as I`ve done that when the crankshaft bearing was about to collapse.

Gerhard

Post by **jcslocum** » Wed Jul 12, 2006 10:57 am

Using the search function, I found this in about 20 seconds: http://forums.ducatipaso.org/viewtopic. ... ine+change

I'm sure there's more.....

Use engine swap as the key words.

lceriani · Post by **lceriani** » Wed Jul 12, 2006 12:08 pm

I am putting another M900 engine on my Paso (I already had one) and I confirm what delagem said:

a lot of details to sort out. Details = money*time!

I had to get:
- A monster engine in good conditions (at least 700/1000 € + shipping)
- Mikuni carburettors (BDST38)
- Air filters (K&N)
- Electronic ignition modules (Pederzini AL2000)
- Ignition coils (Ducati Monster)
- Clutch commands (rod+cylinder+lever)
- voltage rectifier (Ducati Energia)

Relevant Modifications:
- cutting some material from engine to fit in Paso frame
- cutting some material from engine to let rear suspension work correctly
- sprocket-crown re-alignment with iron spacers on sprocket
- tachometer transplant
- electrical circuit modifications to use new voltage rectifier
- exhausts tubes
- carburation jetting

The first time I had a mechaninc doing all the work, but a bad sprocket-crown alignment caused the chain to break very badly into the engine case. Now I am mounting a second M900 by myself, but it's more difficult than it seems... I am really spending a lot of time on it!

:toofar:

delagem · Post by **delagem** » Wed Jul 12, 2006 10:37 pm

Good Lord, Iceriani, you had to do ALL that? I guess I'm glad I didn't pursue the Monster motor...

750Phoenix, I didn't realize you had already dropped the motor and started disassembling it. Well, you're into it now! I was in the same situation with my Paso, but a few weeks searching and I found a small but decent selection of Paso motors to choose from. My total expense was about $500 including base gaskets, belts, etc. I rebuilt the top-end (a good opportunity to learn how to adjust valves!) and reinstalled the motor myself.

With a few mods, a well-running Paso motor will make just as much power as a 750 Monster motor, if your final goal is increased performance!

750pheonix · Post by **750pheonix** » Wed Jul 12, 2006 10:57 pm

Hey delagem, you got off lightly... my bill for taking the engine apart is more than your total bill... I am guessign you have much experience working with Ducati's and a workshop to do these things in...

I am just weighing up the pro's (ummm very few) against the cons (huge expense)... stage. To put it into perspective i could probably buy a good 907ie for less.

delagem · Post by **delagem** » Wed Jul 12, 2006 11:44 pm

Yes, paying a dealer to do these things gets expensive in a hurry! I used to pay dealers to work on my bike, then one of 'em didn't tighten the bolts on a brand new carbon exhaust, which then fell off about 50 miles later. I figured I can do at least that quality of work! I've made plenty of mistakes since then, but its been fun and a learning experience!

It seems like your best course of action at this point is to find a used Paso motor to put in your bike. Maybe you can sell your old motor to cover most of the cost of a new motor, or the installation?

I will catch flack for this, but as much as I hate to say it, there are some Pasos out there that just aren't worth saving... The guy who I bought my replacement motor from had just such a bike. There wasn't a single bolt on the bike that wasn't solid rust.

lceriani · Post by **lceriani** » Thu Jul 13, 2006 11:20 am

If you ever decide to use another engine, be careful that probably you'll have to do all the maintenance by yourself.

At least in northern Italy, usually good mechanics won't put their hands on such radical modifications, unless they did them from the beginning. I brought my modified Paso to different Ducati Services just to adjust valves and carburation, but they all refused to work on it. They say that they couldn't guarantee any work on this kind of motorbike and they prefer to refuse rather than to risk any worse problem in the future...

Personally I think it's a responsible behaviour from them, so if you plan a transplant you should be aware that you will have to spend *a lot* of time on your bike.

PS: my nickname is LCERIANI, not ICERIANI. "L" stands for "Luca"

Post by **paso750** » Thu Jul 13, 2006 1:13 pm

Luca,

I partly agree with you, but I think a Ducati engine is a Ducati engine no matter in what Duc model it ends.
My mechanic wouldn`t mind if I had a testastretta hanging in the frame. Actually he probably would push me to do so just to see if that was possible :laugh:

About all the mods mentioned when changing the engine I wonder if you really have to change:
- to Mikuni - Weber should still fit
- CDI units (Pederzini are just for performance)
- Ignition coils - wouldn`t the old have worked also ?
- regulator - -"- ?
- exhaust tubes - why did you have to change them ?!

The changes to the engine housing to mount it to the frame are understandable to me. I just don`t get why the things mentioned are a must, or did you just decide to change them as you were modernizing ?

Furthermore, the old shifter/brake lever absolutely don`t fit anymore ?

Curious about all this as I had thought of changing the enine myself longer time ago.

Gerhard

lceriani · Post by **lceriani** » Fri Jul 14, 2006 8:26 am

paso750 wrote:Actually he probably would push me to do so just to see if that was possible :laugh:

:laugh: I was not so lucky...

paso750 wrote: About all the mods mentioned when changing the engine I wonder if you really have to change

I just wanted to describe just what I did for my bike, surely some modifications were needed, while others were for performance and others were unnecessary… but I felt that the bike was better with them.
Indeed, what I mean is that when you start such modifications, probably you’ll find other things to change or -using delagem words- you’ll have to work on details. And details = money * time!

If you are interested in what I did, here are some explanations:

I mounted Mikuni because Monster use them and not Weber. I didn’t trust Weber because they cause problems even with original Paso, while Mikuni are good for Monster and (for me) easier to handle. When Gerhard gave me the manual about how to revision them, they become even better.

It was a choice of mine, maybe other ideas are better (for example Dell’Ortos…)

I used K&N-style air filter because I couldn’t manage to build a suitable airbox (as Gerhard did!!!

)

About CDI: initially I was not sure if Paso and Monster units were compatible, so I change them because I preferred not to risk, and then I choose Pederzini AL-9000 just for performance and best tuning. Later I discovered that both Paso and Monster unit are Kokusan, both degree advance is 6° until 1700rpm and raises to 32° until 2600rpm, so probably they are… identical. Surely this upgrade is not compulsory.
An interesting article about Pederzini CDI on a Ducati 900 engine is at http://www.visi.com/~moperfserv/ignition.htm

I also choose to change voltage regulator. Paso generator is 12V 300W 3-phase and Monster generator is 12V 350W single-phase, and consequentially regulators are different. From Ducati Energia catalog I found that Paso spare part (34.8520/8 or 54040011.A) is different from Monster unit (34.8637/0 or 54040081A): both are 12V/25A but Paso unit is “controfase” (counter phase?) and has 6 wires, while Monster unit is “a ponte” (bridged?) and has 5 wires.
Theoretically it's possible to connect a 3-phase generator to a single-phase regulator (i.e. Paso Engine to Monster rectifier), but I was not sure about vice versa. Also due to Paso regulator weakness, I preferred to choose Monster unit and connect Monster single-phase generator to its own single-phase regulator.
I also applied the well-known start relay modification…

Ignition coils are different, too: Paso models have HV resistance = 8800 ohm and LV resistance = 40 ohm, while Monster units have HV resistance = 12,000 ohm and LV resistance = 3,4 ohm. Initially I used Paso units, but when one failed, I replaced both with Monster parts.
With coils I replaced plugs, too: I use Monster’s CHAMPION RA6HC instead of CHAMPION RA6YC. They are very similar, but RA6YC has standard projected core nose, RA6HC has 0,030” core nose projection. According to edelbrock.com, “providing there is sufficient clearance to valves and pistons, [..] initiating the flame front closer to the center of the combustion chamber has a similar effect to advancing the timing. Therefore, maximum timing may be reduced which helps reduce the chance of detonation and provides superior part throttle response. A second valuable feature of this style is a "broader" heat range. The core nose is longer, providing a "hotter" plug at low speed which helps prevent fouling. As engine speed increases, the incoming air/fuel mixture flows across the tip of the core nose, providing charge cooling which effectively reduces heat range at higher engine speeds for increased pre-ignition and detonation protection.”
I don’t know it is really true, but it seems reasonable and I trusted in it.

Paso shifter lever fitted, but I found it uncomfortable with new clutch (that was not original one, but a Surflex special part…). A Ducati Service changed the cylinder with a new one (the only Ducati official intervention on my bike!), but it was useless. Another Ducati Service told me to change the cylinder with a 998 unit with a different rod (this time I had to do it by myself…) and it was slightly better. But the final solution was the Monster lever: it’s adjustable in 4 positions, and with that I had a better feeling with clutch. This is subjective, since my brother (who uses the bike with me) prefers different regulations than mine.

Post by **paso750** » Fri Jul 14, 2006 11:09 am

thanks for the detailled description !!!
That Gerhard guy is actuallly in progress to change airbox to airbox phase 2, which included Mikuni TDMRs and a totally new construction.

Changing coils btw. I think is a good option, but not a must.

G.

ducapaso · Post by **ducapaso** » Sat Jul 15, 2006 4:10 pm

insted of all this work for dropping a sobstitute, maybe it would take a smaller effort make a wider sarch of an original engine, from a paso or a cagiva elefant: it's been used for longer in such a bike!
(I suppose until 1997 or 1998). Upgrading if to paso performance is not hard as anyone can suppose... the engine is basically the same, you just need weber carburateurs and original exaust pipelines

lceriani · Post by **lceriani** » Mon Jul 17, 2006 8:04 am

I read this interesting article about ignition coils:
http://www.tonyfoale.com/Articles/Ignition/Ignition.htm

According to the author, "The maximum current that can flow is determined by battery voltage and what’s known as the resistance of the primary coil. This maximum current puts a limit on the strength of the magnetic field that can be created in a given coil."

So using a coil with a lower LV resistance should give a stronger spark especially at high RPM, when the high current helps charging the coil faster. The drawback is that at low RPM the coil draws more current from the battery and heats the coils and electronic switches more ("this increases the resistance in the circuit which reduces the coil current and thus ignition performance as well").

So probably Paso coil and Monster coil both work with M900 engine, but
- Monster unit should give a better performance at high RPM
- Paso unit is better at low RPM and causes less stress to battery and circuits

Again, it's a matter of tuning.
With my engine replacement I wanted to get also more performance at high RPM. So carbs jetting, filters, CDI, plugs and coils were all chosen with this objective in mind.

Bye!