My brothers 1972 Ducati 750GT needs rebuild.

[swooshdave]

 

It isn't going to change anything but , how did these cases get busted up ?

At the time my brother was a twenty year old Royal Engineer attached to 42 Commando in Malta, he did the whole Green Beret thing in Plymouth. (As an aside, he tells me he was instructed to tell any American who asked what the RM shoulder badges meant that he was to reply "Real Marine" and to stand his ground). It seems getting drunk and riding too fast at the local airstrip did not go together too well, the side cases suffered when the footrests dug into them. He had them welded up over there but now corrosion is opening up the old welds. We think we will build what we can and then rethink, we are both retired now so funds not huge.

 

 

My advice? Unless you have the money do not try to fix a Ducati. I'd probably recommended selling the basket case and buying a couple more V11s. Or whatever he wants.

[czakky]

@68C, they don’t let us do those things anymore....

[footgoose]

"build what we can and rethink"  good idea. Sounds like some good times to be had, and no real loss.

[68C]

Sorry to open an old thread but thought I would carry on with the story.

So, it's now 2021, Covid and retirement has given me time to get back to the Ducati 750GT motor rebuild.  Some inheritance money has enabled my brother and I to spend a little more than we intended on the bike.

Bought a Machine Mart  bead blasting cabinet and started to clean up the castings.  The raised threaded section on the LH case for the clutch adjuster was broken. Also the RH side case support for the kickstart was broken off. Took them to a welder who complained about my using glass beads as they remain embedded in the metal and ruin his weld so he will have them vapour blasted.  Lesson learnt I have now bought some soda blasting medium and recleaned the rest of the parts, at least that just washes off with water.  

Then found the bevel gear fitted to the crank had chipped teeth.  It seems it is a weak part on the 750GT design, any wear and then play in the main bearings mean the bevel gear loses its precise engagement and causes the damage.  The later 860 engine has a different layout with a conventional spur gear driving a lay shaft with the bevel gear, any crank endfloat just makes the spur gear slide in and out without upsetting the bevel gear.  Luckily managed to get one from Australia, Bevel Heaven put me in contact with Vee Two who kindly parted one out for me. 

Now waiting for the cases to come back from the welder.

 

 

[Tinus89]

Lovely story. Can we ask for pictures?

[68C]

On 3/26/2021 at 1:22 PM, Tinus89 said:

Lovely story. Can we ask for pictures?

These are the casting that make up just one cylinder head.  I think there are twenty castings all told and about the same number of ball bearings, the only plain bearings being on the gear selector mechanism and kick start shaft.  Makes the V11 rather simple.