Engine case and trans output shaft damage

[Asmig]

Hi all, sorry to make this my first post but I bought a 2002 Monster 620 from ebay. The seller had stated that bike was a rebuild and seemed honest about any issues that the bike had. I've owned the bike for about three months now and while cleaning the chain after a ride I was trying to troubleshoot why the chain gains and looses tension as the rear wheel is rotated. I was able to narrow the issue down to the front sprocket. This is what I found after pulling the sprocket and cleaning out the build up.



Sadly I missed this little gem when I installed my case saver since I never pulled the sprocket. Too little too late it would seem. 

As for the chain tension issue, the output shaft is visibly bent as you rotate it, which was causing the chain to be pulled at an angle halfway through the sprocket's rotation. 

So given today's wonderful find and the badly leaking vertical cylinder base gasket (another unmentioned issue) would it just make sense to start looking for another motor? This one has 22k miles on it now and runs fine otherwise.

And one last thing, thanks for providing such a great forum full of technical knowledge. Until now I have had no reason to make a post as I've found everything needed to answer all my questions through the search feature. 

[ducpainter]

A motor replacement will likely be more cost effective than a repair.

[Asmig]

Kinda expected that.  As far as the 2V engines go would it be possible to use an engine that didn't come with the 5.9 ecu (e.g. 900, 696) if I swapped the fuel injection and wiring and over to the new engine?

[ducpainter]

Kinda expected that.  As far as the 2V engines go would it be possible to use an engine that didn't come with the 5.9 ecu (e.g. 900, 696) if I swapped the fuel injection and wiring and over to the new engine?

A 900 wouldn't work with your 620 ecu. Is that what you meant?

You could get a motor/ecu combination.

[Asmig]

A 900 wouldn't work with your 620 ecu. Is that what you meant?

You could get a motor/ecu combination.

My concern is will the wiring harness on the bike allow for a different ECU to be used?

I was considering building up a 900 to be used with a 5.9 ECU. I have a coworker who wants to sell me his nemesis ECU and could pick up a properly sized throttle body setup to make everything work together.

[Duckintime]

Another motor might be the way to go although your probably once bitten twice shy about ebay. How in the heck does that shaft get bent? Throwing the chain off the sprocket and getting wedged between the case?

[djrashonal]

somebody is selling a 620 motor on here for 700 bucks! it's got less than 500 miles, maybe check that out?

http://ducatimonsterforum.org/index.php?topic=35463.0

good luck with the swap, and welcome to the board!

[ducpainter]

My concern is will the wiring harness on the bike allow for a different ECU to be used?

I was considering building up a 900 to be used with a 5.9 ECU. I have a coworker who wants to sell me his nemesis ECU and could pick up a properly sized throttle body setup to make everything work together.

I honestly don't know. If they're both 5.9 ecus perhaps.

I do know that the older 1.6 ecu bikes would have different pinouts at the ecu connector depending on model. Meaning a monster ecu wouldn't work on an SS harness.

[Asmig]

Another motor might be the way to go although your probably once bitten twice shy about ebay. How in the heck does that shaft get bent? Throwing the chain off the sprocket and getting wedged between the case?

Good question about the output shaft. I know the bike has been assembled from likely as many as three other bikes. The rear wheel is a 5.5 on there now. The shaft, chain, and original wheel could have been damaged somehow during an accident.

[brad black]

620, 695, 800 and 1000 used 5.9m, and you should be able to get your ecu reflashed to any of them.  altho the 800 and 1000 use a linear tps, so you'd need to fit one of them.  750 and 900 of 2002 also used 5.9m, but you'd probably have trouble finding someone who has the map to reflash your ecu to a 2002 750 or 900.

all throttle bodies are the same 45mm ones for all 2v bikes, even 1000.  altho the idle throttle opening will vary.

1.6m and 1.5m use completely different connectors and don't support the logic that a 5.9m can (side stand switch for example).

you should be able to get a 620 motor quite cheap.  a later 6 speed one would be good.

[2001cromo]

just to add to the above.

I've done the 620/900 motor swap and used the 5.9 system as we got the motor, wire harness and ECU/keys/gauges at the same time.

The wire harness is the same except for the circut that goes to the clutch master. This was the only difference we could find. The 2002 620 didn't have the switch at the clutch master and the 2002 900 did.

We eventually ended up going a different route completely with the ECU, but I'd suggest the nemisis if you do put the larger motor in.

[Asmig]

All great info, thanks guys. Now to find a good deal on a 900

[djrashonal]

All great info, thanks guys. Now to find a good deal on a 900

http://cgi.ebay.com/ebaymotors/DUCATI-96-900-M900-M-MONSTER-MOTOR-ENGINE-TRANSMISSION_W0QQcmdZViewItemQQhashZitem255771cde9QQitemZ160380866025QQptZMotorcyclesQ5fPartsQ5fAccessories

[2001cromo]

you'll be better off with a newer model engine. Specifically one that has the internal oil lines on the left side. That's an old engine and IMO WAY too much $$ for it's condition.

newer engine will have 12mm engine bolts and 3 phase electrics which will all bolt directly into your current setup.