1977 Ducati 900 GTS

[JD]

I'm considering selling my 77 900 GTS. I purchased the bike fairly recently from a dealer not far from where I live. The description of the bike was vague at best, but since I love these old bevel drive bikes, I made the hour drive to see it. Apparently it and another old bike had been purchased by the dealer and left in a shed behind the service dept. over the last few years. None of the salesmen even knew it was there until I showed up to buy it. When I got there, I was pleased with the bike. It did not run, but I knew I'd be able to do that. It had most of the right parts in all of the right places. It does have a Rita ignition. I'll get to that in a moment. The deal was struck and I loaded the bike up and headed home. Well, as I expected, it didn't take long to get it going. I swiped a battery from my old Norton and plumbed it in to the Duc. I added some gas and some leg power and in a few kicks, I got fire. It fired up and idled ok, but the carbs needed to be rebuilt. A few days later, the carb kit showed up and they were rebuilt. Easy job. The bike fired up and idled perfectly. A great, deep rumbling from the BUB exhaust pipes. Now, back to the Rita...I was riding the bike around my neighborhood and surrounding roads. I was ringing it out pretty hard, trying to see what, if any, short comings this bike had. That's when the Rita failed. Not the module its self, but the rotor came loose and threw the timing off. After a disappointing walk home (only 2 blocks) I did my research on the previous owner and was able to locate him and talk with him about the bike. He had owned it since 1987. As an aircraft mechanic, he was meticulous about its service. He added that he had rebuilt the entire engine about 14 years ago, put in some hotter cams and shaved the heads down a bit for better compression. It made sense, this bike feels so much stronger and more responsive than my 2 860s. But, without supporting receipts any longer, it's hard to tell what really was done. He is certain that he's only done about 8k miles since the rebuild. Long story short, I am throwing it out there for the right person. I've pondered just replacing the old ignition parts back to stock, or trying to find the fixture tool for the Rita to time this thing correctly. It has just been sitting in my shop a few miles away from my house. I am open to interesting trades, like Giro eligable bikes or other older Italian bikes, or who knows?
There are probably a ton of questions to be answered, and some pictures to help with the story. Please send me a PM and an email address or phone number. I am happy to discuss the bike and give better details.
Cheers.
JD

[wdietz186]

To time it, set the crank at 32deg. BTDC [just after the intake closes,vert. cyl.] but you probably knew that! You need to set the first blade of the rotor 5.5mm from the pole in the pickup. It turns clockwise as you look at it from the right side. The second blade is 90deg. behind and fires for the horiz. cyl. It is a wasted spark setup meaning both plugs fire when the rotor blades pass the pickup but the extra spark occurs on the exhaust stroke so all it does is provide a tiny bit of light in the cylinder.
The Rita kit came with a 5.5mm strip of steel to use for setting the timing but if you have some brass or aluminum I think a non magnetic feeler gauge would be better.