Thanks for the tips on DUCATISUITE, a bit confusing on first sight but i will definitley use it to overhaul de carbs. Plus the battery tray and the single air filters he uses, look very neat. Here are a couple of pictures of the "sliding black doors" I was mentioning Is the black thingon the bottom of the funnel that - when is closed - lets you have a peek of the carburetor needle underneath when you rev up the engine there is a clear suction sound and the black lead slides upwards to look like this. Well, this only happens in one carburetor. The other one stays closed. If you push the slides by hand you clearly notice some sort of "elastic" resistance and a soft suction noise from the one that operates, while the "broken" one does not present any elasticity at all, it just dont work. thank you again for all your quick responses and kind support. this clearly looks like the right place to ask for help. Sorry that I cannot be of much help for now. unless you want to rebuild a 1990 Kawasaki ZZR 600 where I could help you to dismantle and reassemble it in record time blindfolded!! (arrogant Spaniard .. ) I'll keep posting
Those are standard Mikunis. As @Arquebus says, if one slide is not moving, the rubber diaphragm will be damaged, so no vacuum to lift the slide. Replace both. Fit a jet kit with new needles while you're in there and set the float height to 14mm for both carbs. Check the pilot screws are not seized in their threads. If they are, it is possible, with patience, to drill them out and replace them. If you do need to drill them out, ask me how. I have done it successfully and was able to tell someone else how to do it successfully too - no guarantees though... I can let you have pictures of a template for setting the float heights accurately. If you don't know how old they are, get some new cam belts. @Exige on here can supply some at a good price with a discount for forum members.
Fuel pump/filter and check tank to be sure shits not GOIN to just clog again With a bike that old I would do all That in my basic maint anyway but it's a start If it carbd rebuild carbs jet it while it's out replace all rubber n while I was at it get rid of air ox n replace w something more raw That's just me
Don't alter the float/fuel levels until you have replaced the worn or damaged parts in the carbs.........The level is normally set correctly at some stage in the bike's life. If you do alter the height, make a note of what they were before you alter them so you can revert to them if necessary. The 14mm is an arbitrary measurement and generally it isn't correct.........This is because the pilot jet circuits are reliant upon the float/fuel level as well........this also means that the pilot circuit is in use for quite some way up the rev range, until the main jets take over..........alter the height and you can upset the idle and low revs running. For example, when I first checked mine, one was set at 12mm, the other at 9.5mm..........For both, I tried 14mm, then 13mm, then 12.5mm........I still think they could be lower, IE, both at 12mm. Definitely one of the diaphragms will be split when you finally expose them............If you get really stuck for spares, I have several float assemblies which are used but probably serviceable..........I may even have some used diaphragms which may be OK. Incidentally, when you get the carbs apart and have the main jets and needles, plus the springs on the bench; take a photo of them and post it on here.........that way we can see if you already have a Dynojet or similar kit installed............with those exhaust cans, I expect you may have. You may also find that the float needle valves need changing..................unfortunately it seems that replacing the whole float assemblies is the best way to do this..............you can get the needles separately, but that's no good if the seat in the assembly is worn. When cleaning out the carbs, make sure you clear the cr*p out of the pilot circuits and don't use rags which let small fibres come off them........these can block the pilot circuits.
Wow! A lot of knowledge here on the carbies!! Good to know all this valuable info and also thankyou for all your support. this weekend I will try to dismantle the carbs and post better pictures on the damage. It's my first time messing around with carburetors and I will try to go carefully step by step. On a different topic: Can the non-regulable forks of the 750 be swapped by the ones of the 900 with out moddiffications? Are there other regulble upside down forks (better with radial calipers like the ones on the SS900 FE) from other bikes that could also fit? Old Rider: I did a serach on the forum looking for the member that sells the frame bracing system to avoid cracks with no success. Can you help me on that. Arquebus: Thank you very much for your offering on the diaprhagms. Let's see how they look when opened and then figure out what type of spares, dyno kit, etc.. should i need. Cheers Tom
This a template for a float height measuring tool I made. This makes it really quick and easy to measure your float height accurately. Without it it is really tricky to judge properly. You can always make more than one for different heights
No need for radial calipers, the standard brakes are all you will ever need - they will easily lift the rear wheel off the ground. I improved my forks enormously by putting lighter oil in them. Standard, I think, is 7.5 and I put a mixture of 5 and 2 1/2 in to get something like 3 1/2. I got a lot more dive but they did actually work as suspension then. As standard they are far too hard and I think that is one reason why the frames fail - the frame is flexing because the forks don't As far as I know though, 900 SS forks should fit.
Tom it looks like you have some work there. At least your engine is not wearing a fur coat like the 91 750 I'm currently working on.
Both the Showa early fully adjustable and the later non-adjustable forks will fit without modification (those from the carbed 900SS)........... I'm not sure which forks you have fitted to yours but Old Rider is right about the standard Marzocchis...........I refurbed mine and used the standard SAE 7.5 oil..............(they worked well, but thought they needed to be a bit harder.....I added 10cc more oil in each and they are now rock hard.......too hard).... ......then I fitted fully adjustable Showas which had been fully overhauled........... ..............to be blunt, a well serviced pair of Marzocchis work just as well....... A point worth noting........the Marzocchis are easy to strip/dismantle and repair...........the Showas, not quite so. Yes......Steve (known as Imola on this and other forums) at bbbfabrications.com - Home will sort you out with a frame brace..... If you need diagrams of the carbs, just shout........It may also be worth noting that depending upon where you intend getting your carb spares from, the carbs are the same as used on the XTZ 750 and TDM 850 Yamaha.....jet sizes may vary though. With regard to carb parts (say jets and needles) that you dismantle, you can nearly always recognise whether they are Mikuni or not........Mikuni have a little square logo next to the part size.
Dang! Vaya Por Dios!! I just looked at your thread and will follow it closely. Looks like your bike has seen a lot of "life" (in all forms) Be careful when you open the cylinders,.. there might still be a whole family of racoons living there Very intrested in seeing how you extract the rubber blocks from the rear wheel (please post pics if possible)
thanks a lot for the advice and the carb floaters template. I will definitely go for those frame braces. As for the forks, a friend is offering me a good condition pair of 900 adjustables. I'll think on that, He will have to wait a long time though as (as previously adviced) this is goint to be a very deep overhaul on a very low budget As you say in UK "Time is Money" ... that means, the more time you let pass... the more money you save.
Not much done today. Just removing the front electric loom and carefully tagged all pigtails to be able to reconnect them back (I will reposition some of them following DutatiSuite ideas) As you can see, the frame has been painted several times coat over coat.... and paint was liberally sprayed all over without care (tsk, tsk..) No worries, it is just a matter of brushing, cleaning (spread wax, polish wax,... little grasshopper..) Regarding the bars and clutch and brake levers, mi idea is to do something similar to what I did on the Kawi.
Not sure if it was mentioned, but check the emolsion tubes on the carbs as these can got egg shaped. Also the carbs from a 1000 Exup are the same internally. I bought a set for the internals, got four for the price of two Ducati ones!! I must say I'm a sucker for white frames though, need the White wheels to go with the frame, they are a sod to keep clean though:Arghh:
Cush drive rubbers removal from the rear wheel: Depending how badly they are stuck in there, my own method may work. WD40 or similar around the outside joint groove between the wheel and the cush drive rubbers and let it sit overnight. Find a long M8 socket head bolt and some nuts and washers. Find one washer as large as possible to fit through the holes in the wheel behind the cush drive rubbers (from the brake disc side) and slip it over the bolt. Stick a socket bit onto an extension bar, and use it to poke the bolt through the back of the cush driver rubber. Find a large diameter socket or piece of pipe which will sit on the outside of the cush drive rubber housings in the wheel (sprocket side) which will allow the cush drive rubber to be drawn inside...........put the end of the bolt through the socket. Get washers and a nut on the end of the bolt, and then start winding away...... You may have to leave it under a lot of compression / tension for a while but hopefully it will start to move.......... If it pulls the middle out of the rubber, then I'm afraid you will have to carefully chisel the outer steel case to the rubber and cut it out.
Emulsion tubes are the same as jets. A jet kit has been recommended. I believe the carbs from a TDM are the same externally - same carbs, different set-up. When I drilled the pilot screw out of one of my Mikunis, I replaced it with a TDM one. It was different but luckily all the differing dimensions were actually greater, so I was able to turn it down to match the other one. Not in a lathe though, in the chuck of a drill...
Carbs should be the same as XTZ 750 and TDM 850 Yamaha...... ....although they have a remote throttle stop screw (I made mine from a spare trip meter cable and knob)
Thanks for the tip Lumbux. I also like the white frames. But in this case I think I will go to a totally different paint schema. Not made totally my mind though, but how about something similar to this? Its kind of weird trying to imitate the 900 FE colors, but that orange frame....! Don't know.. just came from a quick one day trip to Barcelona and maybe my head is a bit dizzy.
