Advice please 750ss

So! Just been and had a look see. Very nice young lady, who had got the bike out for me and warmed it up. It looks just like any 15yr old Ducati should, in really good nick but with some muck on it.
All the studs on the vertical cylinder were very black and very magnetic, no signs of cracks around the swing arm pinch bolts. No pitting on any of the disc's or the forks. Rear shock was dirty but no flaking paint on the spring. Everything worked; even the chain was correctly adjusted! Mirror extenders but thankfully original indicators front and back, although it would be hard to change the front ones. Tyres and sprockets ok.
There was a fair amount of paperwork, sadly none from Ducati specific dealers, oddly enough it has had new steering head bearings at 3.5 K and a new clutch pack at 6K. 5 previous owners.

Now to two points on which I would like your thoughts.
The front headlight / fairing was not a standard square type but is of a twin headlight conversion, a bit like the DD one you can get for the ST. The front fairing sub frame looks to be standard and unmolested and there are no home made brackets or wiring of any type that I could see, It looks pukka and everything is a good fit and the right colour, no bodging of holes that I could spy. So that’s something to ponder!
Also it did start ok but then it would as it was warm, but the tick over was crap, too fast I though and with a fair amount of hunting. It did settle down a bit after a couple of minutes, but blipping the throttle made the tick over rise again and stay a bit high for ten to fifteen seconds. When I first started it there was a bit of 'popping' from one exhaust a few (4) times but that disappeared after a few seconds So, sticky cable? (yes! the choke was off, its a carby, Mikuni's), Carbs need balancing? Timing? what do you think?
The lass is going to get it MOT'd and if all is well I shall go and collect it next week sometime.
I was really surprised how small and light it seemed compared to the ST, the seating position was fine as far as I could tell, and no I didn’t take it for a ride........no insurance and no road tax.
Cheers.
 
Sounds good so far...

There were many twin headlight conversions produced for the SS series, all the ones I'd seen use the original fairing frame. Some didnt even use twin lights but just masked off part of the original headlight! Asking for the original fairing panel and headlight might be worthwhile, after upgrading my ST to HID, I'm hoping to do the same for my SS.........

I'd suspect the carbs first for the erratic tick over, there are quite a list of items to check, but balance and even cable routing could be suspects.

Good luck.
 
iconic944ss said:
Sounds good so far...

There were many twin headlight conversions produced for the SS series, all the ones I'd seen use the original fairing frame. Some didnt even use twin lights but just masked off part of the original headlight! Asking for the original fairing panel and headlight might be worthwhile, after upgrading my ST to HID, I'm hoping to do the same for my SS.........

I'd suspect the carbs first for the erratic tick over, there are quite a list of items to check, but balance and even cable routing could be suspects.

Good luck.
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I don’t think there are any 'Bits' still with the bike, she is a lovely lass but doesn’t know much about Ducati's and didn’t realise it wasn’t original. Like I said it looks to be a good job, so I'll think about what to do with it. Firstly sorting the tick over will be priority. As far as HID's go I have seen many discussions about how some kits will mess up the focus of he beams and therefore pose a problem at MOT time, is this true?
 
Sounds exactly like mine is. 20 years old and 5,000 miles on the clock - and the carbs were totally bunged up (along with the petrol pump!) when I got it.

It's a fair bet that this 750 has been the same. Sat in a garge most of its life and the idle jets will be slightly blocked and consequently running lean and it's hanging onto the revs.

If you can hear the butterflys snapping shut it's not the cables or routing. To be honest I've still not got mine sorted properly (a winter job), but I certainly wouldn't let it put you off. All part of the fun.....
 
Since yesterday I have spent loads of time looking at links on here and on other sites trying to find both user manual and a workshop manual. Plenty of sites but none seem to either have the right year (97) or the download doesn’t work!
Any Ideas?
Thanks.
 
Good morning Peeps.
On Monday I went to pick up the bike at last. As since I had told the very nice young lady that I would buy it, it has done nowt but sling it down with rain and been very Brrrrrr!
Monday looked as if it would be a good day so I arranged to collect it around midday. When I got there it had been MOT’d and Taxed! Also she had taken it to the garage and pumped up the tyres and washed and polished it for me….very nice too!
I had decided not to use the motorway so set off on my pre determined back roads home, some 40 miles, at the first roundabout I encountered an issue. As I mentioned earlier, the tickover was a little erratic, ERRATIC?????? Well think of any number between 1200 and 3500rpm and that’s where the tickover was! Nice, especially when expecting it to slow down on approach to a corner, sometimes it would, sometimes it wouldn’t. Stood at the lights I found that if I let the clutch out whilst holding the brakes on it would slow to 1200rpm then pull the clutch in again and it would stay there. Well for ten seconds then start to climb again. It was more annoying than anything. Once off tickover the bike ran really well, very well in fact and it was surprising how easy it was to ride compared to the ST. There is some misfire on tickover but not at any other point not even on the overrun.
Anyway, it also started to @@@@calate down so I only road it cautiously on the way back.
Today is the first day I have had chance to go and have a poke around. Now it is very cold here so I thought starting might be fun, but Oh no! not at all, choke on, press the button and off it went: straight to 4000rpm, stayed there for five seconds then stopped!!!!. So a little less choke then? Yes that worked and this time only 3500rpm then stopped. Anyway with a little feathering of the choke and throttle it went ok and I got it warmed up but the tickover is rubbish. I took the airbox lid off and thought I had found the issue as there were two bloody great pieces of black plastic stuck in the inlet tracts. Ah! I thought, Choke stuck on, then I remembered they are CV carbs and sure enough starting the bike and blipping the throttle made them jump up and down, and they seem to be, to the naked eye that is, quite synchronised.
All the connections cables and bits and pieces look to be unmolested with no sign of any insulating tape anywhere. Everything seems to me in place and well maintained even the battery terminals were clean and well greased even the plastic terminal covers look clean and in good order. It has only done 13K and has not a bad service history but it has only done 170 miles in the last five years. There is some road muck on the inside of the fairing so I think its been well polished on the outside, but due to the lack of miles not much has been done with the fairing off, which will be my next job, Once the Haynes manual gets here. By this time my feet were numb so I decided to return to the warm and have a cup of tea! (Actually I have my ironing to do and you know how compelling that is????). I love it when you find something like this that needs fixing, It cannot be too serious as the bike runs really well. It’s a good way of finding out what goes where.
One thing I did think on the way home was that my legs are a touch to long so my knees are really bent, so some adjustable footrests may be an idea………any recommendations anyone?
Stay safe.
Chris
 
I would guess blocked pilot jet(s) with sitting and maybe a sticky throttle cable is the root of your rough running and cutting out when cold. Check the choke is opening and closing properly as well.
Never heard a complaint before being cramped on the SS. If you sat on my bikes for 5 minutes you would think an SS was an armchair! :lol2:
You could probably get some fleabay universal pegs but don't know if they would make it better or worse as the hangars are a fair length already on the SS.
I would suggest surgery if all else fails. ;) :)
Sure you will love the bike once you get used to it.
 
Chris, yer pilot jets are bunged up....inevitable result after naff all miles in years. You'll just need to take the carbs off (as a pair, don't separate them) and take the float bowls off then get busy with the carb cleaner, compressed air and possibly some strands of wire from some electrical cable. The other thing to check is that the diaphrams are ok - take the black plastic caps off make sure the aren't split or perished. Be very careful though as there is a tiny o ring sitting under the diaphram and you don't want to lose that. Great job for when there's nothing on the telly over Christmas!

Mine was/is exactly the same. I still need to do a bit of fiddling as it's not right yet, but it's a lot better than when I got - and it was exactly as what you're describing.

Cheers,

Kenny.
 
deputydawg said:
Chris, yer pilot jets are bunged up.... and possibly some strands of wire from some electrical cable.
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Kenny's advice is good except for that bit about the strands of wire. Brass jets are very soft and using a bit of wire can easily enlarge the hole slightly. maybe not a issue with a 1.40mm main jet but could make a significant difference to a a tiny 0.425mm pilot jet. It's better to use a stiff bristle from a brush.
 
iconic944ss said:
Some nice Woodcraft rearsets and other Xmas presents available in the USA, here:

http://motowheels.com/ag-67874.34347.67911-1994-ducati-supersport-900.html
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I,ve looked at the woodcraft one and need to work out what adjustment over standard they will give me. They look doody but so they shoulod at that price! Been jumping about on the bike this morning and have realised that I need to adjust the position of the actual brake and gear leavers as they are to high for me at the mo, so my intention is to fart about with that a little. However carbs are the main thing at the mo. Can not wait to get then off and on the kitchen table. Waiting for the haynes manual tho' as the WSM has about five hundred pages on how carbs work and combustion processes and bugger all on how to set them up.
Nice stuff on that site. keep looking at the FCR's but there lots of other stuff I can do for half that money.
Temptation......... Temptation.........Temptation!
 
Derek said:
Kenny's advice is good except for that bit about the strands of wire. Brass jets are very soft and using a bit of wire can easily enlarge the hole slightly. maybe not a issue with a 1.40mm main jet but could make a significant difference to a a tiny 0.425mm pilot jet. It's better to use a stiff bristle from a brush.
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It's all good stuff chaps, actually I was about to use a number 8 masionary drill on the pilot jet. Thought 'i'll unblock you, you little bugger' maybe not then!
 
Just more or less completed the same job of getting the carb linkages, jets, bowls, etc running freely. Taken about a week or so of patient spannering, freeze spray, plusgas, drilling and burner torch and so on. All set to go now. At last. Take your time.
 
rockjock620 said:
Just more or less completed the same job of getting the carb linkages, jets, bowls, etc running freely. Taken about a week or so of patient spannering, freeze spray, plusgas, drilling and burner torch and so on. All set to go now. At last. Take your time.
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Pete! I've got a 7lb. lump hammer, will that do?:comp2:
 
schrimy said:
I,ve looked at the woodcraft one and need to work out what adjustment over standard they will give me. ............ keep looking at the FCR's but there lots of other stuff I can do for half that money.
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Some of these rearsets will give you more ground clearance but more cramped.

And my worthless opinion is if you want to go faster sell the 750 and buy a 900. By the time you buy carbs and spend loads of money sorting out jetting etc you would be easier and cheaper changing bikes.
750 isn't that slow. It revs better than the 900. Suggest you get used to it and if you need faster change bike then......
 
schrimy said:
I,ve looked at the woodcraft one and need to work out what adjustment over standard they will give me. They look doody but so they shoulod at that price! Been jumping about on the bike this morning and have realised that I need to adjust the position of the actual brake and gear leavers as they are to high for me at the mo, so my intention is to fart about with that a little. However carbs are the main thing at the mo. Can not wait to get then off and on the kitchen table. Waiting for the haynes manual tho' as the WSM has about five hundred pages on how carbs work and combustion processes and bugger all on how to set them up.
Nice stuff on that site. keep looking at the FCR's but there lots of other stuff I can do for half that money.
Temptation......... Temptation.........Temptation!
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Stage 2 dynojet kit monster or 620i headers (larger dia) and a BMC filter, cut the top off the air box and let the motor breathe!
 
Forgot to add, you can fit a 600 flywheel which is a good bit lighter it will allow the motor to spin up a bit quicker.
 
Good link Frank, but it stops short at the bottom of first page. Are there more?

it doesn't tell you how stuck the fasteners/jets/linkages can get. Lump hammer deffo not needed. Patience young Skywalker, patience.

Picture inserted twice for some reason. Me being a dope probably.

I had to cut the housing for one of the pilot jets to release it. Too much screwdriver had damaged the slot off the end. Built the housing back up with chemical metal. Seems OK. Now to clean and service them fully.
 
Float height anyone??

I have just taken my carbs off, taken them to bits cleaned everything at least twice and am in the process of putting it all back togetehr. Then I thought I might as well check the float height. I remember thatthis should be 15mm? Now measuring what I think is correct, from the mating face of the float bowl to the top of the float I get only 9.7 mm, hopefully the picture will upload, amd I checking this correct? both read about the same, can they really be this far out and still work.
Advice peeps, just to save me eating more turkey and drinking even more beer.
Ta!
 
Cheers for that Frank.
I had read this and many others but was still a little unsure where you measure the float height to. However I have taken the plunge and measured it to the top of the float. All the information I have read suggests these CV carbs run at 14mm, so thats what I've gone for.
I did think I might get them back on today but I have family comming back here, so more cooking drinking and merry making for me. Also one thing about taking the carbs off is you can actually see how dirty the engine really is in those hard to reach places. So next time I get some peace and quiet, out will come the gunk, toothbrush and hot water.
 
schrimy said:
Cheers for that Frank.
I had read this and many others but was still a little unsure where you measure the float height to. However I have taken the plunge and measured it to the top of the float. .
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Yes! to the top of the float chamber is the correct place to measure the float height. I was taught to measured the float with the carb tilted enough so that the float is just applying pressure to the float needle say 45 degreeish , you will get a different reading inverting the carb fully.
Adjusting the float height is a fine tune to the carbs usually done after installing different needles and jets to what was installed by the factory.
 
Well the sun came out today!

Well I’ve had a jolly afternoon. As the sun was out I decided, having stripped, cleaned and assembled my carbs, to go put them back on the bike. It also gave me the opportunity to remove the fairing and give everything a good old clean. So out came the gunk and assorted brushes and once everything was given a good old going over I washed everything off with very hot soapy water. The engine looks OK given that the bike is 15 years old, it has the usual flaking paint but all the nuts bolts and fasteners are there and it came up a treat. So I dried everything off and set about putting the carbs back on. One thing I didn’t take a photograph off when I took things to pieces was where the negative (earth) cable attaches to the frame. I found the cable in the bottom of the fairing so I have assumed it had fallen off when I took the carbs and air box off. Looking at the shape of the cable it appears to go between the frame lug and the mounting bolt for the rear of the air box/ battery unit. If this is so it’s a dam poor place as most of this area is covered in paint. I can see me getting some longer cable and some fittings and using one of the redundant lugs on the inside of the frame once I have polished them up that is.
Anyhow, Having got the carbs back on the bike, It started no problem, well once I had noticed that I had accidentally knocked the kill switch to the stop position it did!
The issue of it idling at 3K has gone, however it still is not right. On starting with the choke in, it immediately ran at 4K but backing off the choke it ran at around 2k until warmed up and I took the choke off altogether, then it ran at around 800rpm and gradually got slower then stopped. So I adjusted the idle speed screw. But this seems to do little then all of a sudden it will run at 2.5k, backing the screw off and blipping the throttle makes it go back to 800rpm! Hmmmmm!. So I adjusted the idle mixture screws by half a turn each and immediately things were better, It will tick over very nicely at 1k, blip the throttle though, and it will stick slightly at 3k and then slowly (over 5seconds) go back down to 1k. So something still not right! But it’s a vast improvement over what it was like. I have a manometer so next job will be to see how much in sinc the carbs are and I will get some new throttle cables as the old ones are a bit rusty and twisted, (like me then!) although they seem to move freely enough. I have a suspicion that someone at some time has tried to fix the high tick over by adjusting all the screws they could find as when I took the carbs off one idle screw was four turns out the other, two. I set them initially at two and a half as that what it said in the book.

Here is a picture of the very expensive Ducati corse lower fairing fixing upgrade that someone has kindly added at some point, That’s another job to do then!

So Peeps, any ideas on the earth cable fitting, and where can I get some throttle cables from, Yes I’ve looked on flea bay already.
Take care.
 
A "MAN"ometer - aces.

Womanometer...............now that would be acerer. Adjust your female to the correct pressure.

God job on getting it running first time.
 
rockjock620 said:
A "MAN"ometer - aces.

Womanometer...............now that would be acerer. Adjust your female to the correct pressure.
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Yeah right Pete! What chance of ever getting that right:lol2: I once tried running a woman at 186psi but kept getting blowouts!!!!

Anyway, where does your earth cable ground on your 900?
 
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