Salve Carlo

Ti dispiacerebbe spiegare cosa è successo a Spino ?

The article in Motosprint just said something about "rotto la sua Ducati" and then starting (AND winning) in Gr5.
Hope the damage is not too big ?

ciao
joseph

Maybe he just had to visit a tree? He and the bike look OK. MikeV

Ciao Amici, Unfortunately I twisted the crankshaft and connecting rods, I adjusted for the next race, in Frosinone and I still broke the crankshaft, now I have removed the engine block for the second time and I will try to understand where the problem is, the bike has 7 oil pressure bar at idle speed, but I destroyed two crankshafts and 4 connecting rods.
I got on the mono 500, which had been standing still since 2017, and I won three consecutive races, in a few days I will open the 1100 engine and will continue to swear and fix it.

Ciao Carlo. I said to keep the front wheel on the ground, and not exceed 11,000 RPM1! Which one did you do? Both?

Sorry for your grief. Is this the engine you have used a while, or is it a new one?

Sympathy,
MikeV

Mike, Carlo sure tries to keep the front wheel on the ground. He's even checking it after the corner.
Still having problems staying between the lines though.
Picture taken from a movie, gravel flying.

Hi Friends, excuse me if I am very discontinuous in my answers, the engine block that I have seized the crankshaft connecting rods, is the engine block that I use on the Moretti 010, that is modern bikes, practically a Hypermotard with carburetors, the one in the he last photograph below is the 750 tt1 and would be the Moretti 005, which has now been standing still for three or 4 years.
I changed the bushings on the crankshaft by doing all the possible procedures, using a bore gauge with three measurements, 12 o'clock, 10 o'clock, 14 o'clock, and adding the measurements and dividing by three, leaving a connecting rod clearance of 5.5 cents of millimeter, I also used plasticage, confirming the measurement made with a bore gauge, but alas, I broke the crankshaft and connecting rods twice.
Now I have reassembled the used crankshaft and connecting rods, I checked the ovalization and waxed less than a hundredth of a millimeter, but now I have made a class A shaft with class B connecting rods with 4 red bearing shells coupling, and I have closed everything.
Let's hope it's the right time, I found two breaks I think due to shrinkage caused by no minimum running-in of the engine, since I don't have the possibility to do this, in uphill races you can do a free practice session, but you struggle to to run in, now I should have more than 5.5 cents, I think 6 cents, it's as if a bike has already done 1000 km.
Fingers crossed.

I must ask... is it both rods seizing or the horizontal only?
-Cranky-

horizontal only

Damned! I would really like to hear more about this observation of yours Cranky.

I have long noticed that more horizontal cylinder scuffing seems normal with these engines, and attributed it to Isaac Newton (gravity). Makes me wonder about other old Italian engines with one H cylinder. Is there something else going on? Please tell us.

MikeV

I've seen some failures and have been involved with some analysis. Various issues contribute to big end failures. Oil passages have sharp edges the way they are drilled and I've seen stalactites hanging in these passages locked in after heat treat. Those passages can be worked out with some creative swear words and abrasive rope.
The finish on the journal is rather rough and needs micro polishing and certainly setting bearing clearance on a race engine especially this one should be set on the loose side....on the order of .0025-.003 inch.
Oil pump pressure relief needs to be checked for smooth operation. This is the style that is built into the side cover and flaws have been observed. The relief spring needs to be shimmed to verify 100 PSI pressure at say 3500RPM with hot motor.
I communicated directly with Carlo as the language barrier can be an issue. I think he had things figured out already... Hes no amateur.
-Cranky-