having an engine start up trouble.

[Aussie Steve]

"I would strongly suspect an electrical fault seeing as how you only have what appears to be weak sparks."

"Yes but you really think that is causing it not to run ?? Considering that he can get it to fire up....and apparently for more than a few seconds....with starting ether ??"

Yes!

As you stated starting ether is a lot more volotile than plain gas and will ignite if you look at it wrong. Jokes aside a plug under compression with an already weak spark will fail to spark couple that with more than one and the motor will run intermittantly at best. But now the whole story is out re the rusty fuel tank...which was replaced so the later bump is not relevant... and rust in the carbs the theory changes to plugged carb jets. One thing I already stated is remove the plugs and check them for (a) dryness or (b) wetness to identify the possible fault. It has to be either ignition or fuel......or perish the thought both!

Good luck

[cyrusyn]

Plugs were wet.
Does this mean one of the jet is clogged and is left open so that a lot of fuel is going into the cylinder and screwing the air/fuel mix ratio? Could this be Idle jet or high speed jet?

How do I clean up the clogged jet? I am thinking about cleaning the float bowel but if jets are clogged can I use fuel system cleaner or carb cleaner?

[cyrusyn]

Just drained the float bowel. Nothing that looked like a rust came out. Only fuel came out.

After drainingthe float bowel, I started the bike with a dose of ether a couple times. It fired however unlike last time when it lasted for more than a minute, everytime I started it didn't last one or two second. Could this mean something else?

[Aussie Steve]

Ok now you are looking at an electrical fault....probably. Test the coils for resistance....specs should be in the manual...or printed on the coils... and voltage to the supply side. If you are getting 12V at the supply side then the fault is either the plugs, caps, cables or coils in that order of checking. If you do not get any supply voltage then the fault is in the ignition circuitry or possibly the ignitor is faulty. Also check for loose/crudded up battery connections, and or battery state. There may be sufficient power to turn the motor over but not enough to fire it too. You will need the wiring diagram to isolate the ignition circuit. One thing to do a quick check is to find the ignition relay and wiggle it about a bit....check for loosenes in the monting block and also that it clicks cleanly on and off with the ignition switch...any lag can point to a fault. I seriously doubt now that the fault is fuel related...unless you have four sunken floats... but then you would have fuel spewing everywhere.

Good luck

[cyrusyn]

>unless you have four sunken floats... but then you would have fuel spewing everywhere.
How would fule spew everywhere?

Thanks a lot for your long reply. I will look into the electricals. I just took carburator off and am about to disassemble it to check the floats and the jets.

This is my first time taking carb apart. What are the things that I need to be careful with from your past experience?

[WildBill]

I wonder if you damaged the plug wires when it fell over. Might be as simple as wires.

[Aussie Steve]

The float controls how much fuel is allowed into the float bowel via the float needle. If the float isn't floating then fuel will continue to flow untill it fills the carb completly and thus flows out of any opening it can find. I would leave the carbs for now and check out the electricals as they are easier than pulling 4 carbs down.

When dis-assembling carbs I always do one at a time so I have three to use as a reference. I also use a digital camera to take reminder photos of how things are put together. These can be used as a cross reference for any remaining carbs so any glaring errors or omissions can be seen. If possible leave them on the mounting rail. Take care not to lose any tiny bits and remember the jets are very easilly stripped or damaged. You will probably end up stripping a few screw heads but as I always cut a small slot in them before re- assembly it is a moot point. Some like to replace them with allen scews. A small eye glass is usful for detecting any wear on needle tips etc...although if in doubt its better to replace any parts that show any wear.....you don't want to rip them off and apart again!

Absolute cleanliness is needed and a piece of white cardboard can help to place all parts on. Access to a compressor is preferable for blowing small jets and passages out, although a bicycle pump can be used. I have used a syringe full of Kero with a short length of tube attached to the end in the past. The kero will ruin the plunger of the syringe so get several....a vet supply is a great place for the larger types.

Be warned, however, it is very easy to get confused with carbs. Also if you remove the cable linkage a resync will be necessary. Finally a new gasket set for each carb is preferable to cutting your own and will be needed.

Take a photo of all linkages and plumbing before you pull anything apart and you should be right to go. A good set of screwdivers is a must and be prepared to use a set of vice grips on the float bowel screws as they will be very tight and the head will probably end up being stripped.

Good luck and remember............. check the electricals first, battery too, if it is the same one after the tip over.

[cyrusyn]

Aussie Steve and everyone, thanks so much for your advices. I checked all the jets on the carb and they were clean. No clogs.

But I found the two T-fittings left open without a plug or leading to any connections.



In above picture, the number 15 and 16 were missing and 4 and 5 were left open.
Could this have been the cause?

Otherwise, I am now moving onto electricals. I am going to recheck the spark plug gaps tomorrow.

[Aussie Steve]

It doesn't make any difference if those are on or off...they are breather pipes and only vent to the rear of the bike. What year is your bike again? On my 02 B12 the carbs have a single fuel entry point and a metal fuel rail to the remaining carbs. I am only asking as a setup like that can have problems with kinked hoses etc...