Hi All, So I've been pretty bike mad all my life, And I love all kinds of bikes, I pretty much was a Kawasaki fan until I've just hit middle age and I took the plunge by buying an oldie Ducati. My first ride home I was like what have I done this things a bag of nails, but having ridden some 50 miles apart from suffering back ache and leg cramps the old girl is growing on me. Here are some pictures I would like this bike to really reach it's potential it's all original, anyone in London or surrounding counties that can point me in the right direction with getting the bike running it's best and sourcing parts etc... would be most appreciated.
Nice bike, have a search on the forum, there is a great post by our French friend he seems to have his running sweet. 91? Is it a late registration? Cheers Gaz
Hi yes it would seem it's a late registration, I will have a good search on the forum to find out more.
Yes, it's a late reg. They made these 900supersport in 1989 and 1990. A highly flawed motorcycle. Don't brake in a corner , the bike tends to stand up and throw you off. Carburation was a modified car system from an alfa or fiat ( to pass more stringent pollution regs in Europe and USA). They iced up and rarely were set up properly and the big air box means they needed a low pressure fuel pump ( the big tank is hollow , with no fuel above the carbs ) Good points 17" wheels from an 851 and lightweight swing arm from verlicchi, the grame designs showed no logic with about 140mm of trail on the non adjustable 40mm forks and a very slow turning bike was the end product ( almost as slow as the 1970's 900ss ) Best Web site https://forums.ducatipaso.org/viewforum.php?f=13 Air-cooled clutch had the lifter on the righthand side and would get damaged by clutch material. The paso used a similar engine. Later 900ss were a different engine , and the frame was better and had usd forks. they made only 2000 in 2 years worldwide , and were expensive and difficult to sell. Parts are mostly difficult to get - and expensive. I have a 1989 900ss site won't let me post a picture
Hi @kwakamoto and welcome! That’s a fantastic bike you got yourself. I personally do not think it’s « highly flawed » in the slightest. Quite the opposite, actually. It’s the very first belt driven 900SS. It was mainly sold in Japan and Australia. These markets welcomed the model before others (Europe/US) which had to wait for the 91 model (the following generation) to get what it was (market segment). It has its original mirrors and turning indicators, if I am not mistaken ? That’s brilliant ! This bike works wonders, especially in it’s original configuration (including the OEM Weber 2-barrels carburetor. Don’t believe the crap written by the press back in the day. They all apparently got to try the same ill-tuned bike. Blame Ducati sales department for that…). So far, the only downside for me is that it is a fairly small bike, especially for a 900cc, and was not meant for riders with long legs… But I regularly ride it on small 3/4 days tours (800 to 1000 miles) and it’s surprisingly swift to throw into corners, as you may have already noticed. Much more than my 916 with its original 3-spokes wheels. So it’s an absolute blast in curvy roads. Here’s a bit of reading about mine: https://www.ducatiforum.co.uk/threads/1989-900-supersport-in-france.95284/ I actually purchased a pair of these, refurbed both of them, sold one and kept one. Are you planning to work on it yourself ? Will you ride it lots? Let me know if/when you are looking for specific parts or documents and I should be able to point you towards decent stores and vendors. Cheers!
You can download all these for free as a starter: (1990) 900 Supersport - User manual : https://app.box.com/s/s6d7qjaaite4dkps1o8672egq5fse0gb (1990) - 900 Supersport - Workshop manual : https://app.box.com/s/7u0incfpwbpxw1dmyqv4 (1990) - 900 Supersport - Spare parts catalog : https://app.box.com/s/8rb7ayuuif2qs7qncgo5kejzuwld1h3j (1990) - 900 Supersport - Technical Data: https://app.box.com/s/9edju4oizdzps0e4eigx6wwnohiti3bf (1990) - 900 Supersport - Frame, swingarm, forks: https://app.box.com/s/x8e93h3dojj0wq8dzicth2dv2hb6es62 (1990) - 900 Supersport - Wiring diagram (colored): https://app.box.com/s/rqlews1vt1onid6b96bi Enjoy!
Hi thank you for your input, yes indicators and mirrors are original although useless. I am planning to use the bike only one Sunday a month but try and make the most of it. I will be doing some work myself but I would like to see it restored just like new and might have to send it to the pros. I don't have much equipment to tools and I have very limited space. I read your project thread and it was very cool would be nice to find someone closer to home to hang with and work on the bike. It's a shame your not any nearer. I really like what you have done with your bike and hope to get mine in a similar state. Any ideas why at low revs in 5th gear it's sounding like a helicopter? Also what can I do about the over rev as when I'm off the throttle it takes a while to return to its idle speed. Andy
What rpm is it sounding like an helicopter ? Hanging revs are either an air leak - say from worn carbs ? Or another possibility is one or both of the slides are sticking because of grit or congealed fuel etc A good clean and inspection of the carbs should show the problem ( they are an old design 1st used on 1960s Italian cars - so expect 'character' lol ) The carbs aren't great anyway ( icing and evaporation of fuel being 2 problems ) The website goes into some of the problems , also they weren't designed for modern ethanol fuel that causes more problems - my bike has had the carbs replaced by 41mm dellorto's with accelerator pumps - many now go for the cheap Chinese keihin carburettors that have flooded the market. These bikes look fantastic, but they were all built on a Friday afternoon after a couple of bottles of cheap vino Lol - that character Always use petrol with the lowest ethanol - and use a ethanol removing / reducing additive ( I also use a lead replacement additive to lubricate the valve seats.
The carb on this bike is a Weber 44 DCNF - 118. It does not have slides (like FCRs), but butterflies. Carbs (not only this Weber) all need a good clean and refurb when having been left unused for some time (petrol gum residues, gaskets drying, etc.) The best way to start fresh is to have them professionally cleaned in an ultrasonic bath and then refurbed with a kit like this one: https://classiccarbs.co.uk/product/...tor-servicegasket-kit-lassic-ducati-750-paso/ As far as engine not going back to idle, if your throttle cable is not the problem (i.e. everything is clean and lubed), I read several times that it can be caused by a poor synchro of the two barrels. So my advice, once the carb is clean and refurbed, is to get it properly tuned. It’s not complicated to do, but you need to be methodical and a few tools for that, like a carbtune for synchro, and a gaz analyser or O2 sensor for idle mixture set-up, etc. Look at this Ferrari Dino 246 blog (carb tuning #1, 2 and 3 entries from August 2014) and you will discover the wonders of a well set up Weber. Yeah, they had 3 of these stacked on Ferraris. Not just Fiat.. http://dino246blog.blogspot.com/2014/08/carb-tuning-1-weber-dcnf-carbs-and.html?m=1 Finally, yes, tell us what it is you call « low rpm »? After a proper carb tune, both bikes I worked on are fine down to 2000 rpm, but in 1st or 2nd gear. Never get below 4000 in other gears. That’s considered engine abuse on these. They do sound a bit like a 4-stroke lawnmower down there, like all D2s, though, I would say. These 904cc Desmodue (D2) twins (the same used on Pasos) like to operate above 4000 rpm (and up until 7000. Power goes away reaching 8000). I personally find the original transmission 15/39 just fine, but should you need to change your chain and sprockets, you can consider something shorter which will always help below 3000 rpm. Like 15/41, for example. PS: Should you decide to head down south on that bike one day, you’ll find me just before you hit the Alps. But I can guarantee you will find people in the UK that know how to work on these. PPS: Ride a 748/916/996/998 and you will understand what a useless mirror really is. Ride a 939 Supersport and you will experience a REALLY useless mirror. In comparison, these round Vitalonis you have on your 900SS are nearing perfection…
...as above... Don't lug these engines - they're big twins that like to rev a bit! Anything under about 3500rpm in any gear is lugging it.
I would be taking that to Geoff Baines at Baines Racing (Silverstone) if 'surrounding counties' could stretch to Northants ... probably not.
"The carbs aren't great anyway ( icing and evaporation of fuel being 2 problems )" Sorry, but not a lot wrong with these carbs when fitted to cars, tuned and repaired many over the years, they are just not ideal in this configuration. There are owners on the Paso Forum who have persevered and got their bikes to run reasonably well as std but a swap to later Mikuni carbs and manifolds is one route although air filter assy will need adapting.
