1992 400sf carb removal

billgrundies · Post by **billgrundies** » Mon Apr 11, 2016 9:57 pm

hi,this may be of use to someone. to remove the carbs is not too bad a task. if you need to, take photos for re- assembly. put bike on centre stand and remove tank, seat, side panels and 2 plastic carb cowls. drain fuel from carb bowls into a container by using a tube plugged onto the nipple under each bowl and undo the brass screw next to it. do this on all bowls but note there will still be fuel in the carbs so take precautions. slacken the pozidrive screws on the clamps on the carb to airbox (x4) and carb to inlet rubbers (x4). remove the 6mm bolts (x2) holding the airbox to frame and take off cdi unit to give more clearance to pull box back. unclip the tube at top of carbs to airbox. pull airbox back as far as possible and pull carbs from engine, they will be tight and will take some effort as there is not much space to work in. the carbs will now be removed from the right side of the bike. place a cover on cylinder head to stop scratches and soak up spilt fuel. take photos or sketch throttle cable routes, take measurements of cable adjusters to give an idea on re-assembly. unhook the choke cable nipple and undo both throttle cable adjusters and unhook their nipples. lift carbs away. whatever work can now be carried out. reverse process to refit. took mine off to clean, removed bowls, floats, jets etc etc. set mixture screw to 2.25 turns out. set all the butterflies on sync screws by eye. fitted choke and throttle cables back and done all adjustments with carbs resting on engine before fitting. did not have to adjust after refit. set up sync gauges and did not have to adjust any sync screws either.

zoltan · Post by **zoltan** » Mon Jun 20, 2016 7:59 am

Hi Guys!

My name is Zoltan, I am from Hungary. I have a superfour from 92. I had starting problems, so I decided
to clean and rebuild the carbs. I finished the work, but I have two connections on the carbs without
pipes, and I do not know where to connect them. I marked the missing pipes with green on the picture.
Could you please help me?

Thank you in advance

Zoltan

Patch29 · Post by **Patch29** » Mon Jun 20, 2016 11:39 am

Hi Zoltan, fairly sure those ones are the breather tubes, will see if I can locate the parts diagram for you...

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Patch29 · Post by **Patch29** » Mon Jun 20, 2016 11:51 am

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Superjack44 · Post by **Superjack44** » Mon Jun 20, 2016 10:37 pm

The open ends fit into a slot on top of the airbox next to the breather pipe that comes from the cam cover

zoltan · Post by **zoltan** » Wed Jun 22, 2016 2:02 pm

Thank you guys, you helped me a lot!

Best Regards

Zoltan

Patch29 · Post by **Patch29** » Fri Jul 08, 2016 11:21 pm

Hi Zoltan, how's the bike running???

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zoltan · Post by **zoltan** » Mon Jul 25, 2016 3:01 pm

Hi!

It is not running at all. I could not even start the engine. I took it to the mechanicer, he said
he must clean the carbs. I am looking fowward to it. His cleaning stuff may be better than mine.

Zoltan

billgrundies · Post by **billgrundies** » Thu Jul 28, 2016 8:59 pm

hi, I assume you have done the basics such as spark test, clean air filter, fuel in carbs, fuel getting to cylinders etc. a few problems I had getting my bike running were as follows. the bike had stood on its side stand for a long time. first no fuel was getting to the carbs due to the rubber diaphragm inside the fuel tap drying up and bonding over the fuel exit hole. if you remove the tank, turn fuel tap to on no fuel should flow. on the side of the tap is a small bore pipe which went to cylinder no1. gently suck this pipe and this should lift the diaphragm, beware as the fuel will flood out. if no fuel then remove screws, dismantle tap. if diaphragm is stuck don't pull it until you soak it in WD40 and leave for a while. if fuel flows as soon as you turn tap on the diaphragm may be split and needs replacing. the carbs were blocked by the fuel setting in the bowls and jets. drain and remove the carbs, remove the float bowl and slide out the pin holding the float in. take off the float and float needle. where the float needle sits there is a tiny filter you cannot see. remove the brass screws and jets and clean and clear all the minute holes. screw the mixture screw in and count how many turns until it lightly seats. then screw out and clean. use carb cleaner in a spray and airline if poss.(gloves and goggles). clean carb body also. the hard part is getting the brass parts out as they are often seized in and being a soft alloy damage very easily. once totally clean reassemble. you can set the butterflies by eye on the adjusters quite well before refit.

billgrundies · Post by **billgrundies** » Thu Jul 28, 2016 9:33 pm

hi again, the float is preset and cannot be adjusted. I could not find info on float height so I used the clear tube method to prove all carbs had fuel in all at the same level. you need 400mm of small bore clear tube. set the bike on level ground and upright. push the pipe on the drain nipple on the underside of the float bowl on carb no1. hold the tube vertical on the side of the carb then slacken the brass screw next to the nipple. fuel will trickle out and rise up the tube. I found that the fuel rose about 8mm above the horizontal edge of the bowl where it joins the carb. no2 carb is done in the same manner and is also held against no1 carb. go to other side of bike and repeat for no3+4. all should be the same. I had no1 carb flood and engine went with a bang

1992 400sf carb removal

1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal

Re: 1992 400sf carb removal