Update.. Tipped bike upside down as suggested. Fair bit of fuel come out!

Heated up the plug, put it in...

Nothing!!!

Doesn't even try to fire at all??

I give up now. I like a challenge but this is a joke

Have you starting fluid?I know it's not recommended for bikes but when I have a really stubborn bike I will use it sparingly. Pull the plug, squirt some in the hole, quickly re-install the plug and kick (if it is a carb issue shooting it through the airbox won't always work). Generally if it fires with starting fluid it tells you it is not a spark issue. If it starts and dies once the fluid burns off it's either a fuel or really low compression issue. If it doesn't start at all it is usually spark related. These are just generalizations but it is a good diagnostic tool to help narrow down possibilities when you are stuck on a bike.

yeah, ''easy start'', as mentioned above. if it starts on this and you have put the carb back together ok, and you have yet to look at the reeds, then its looking like the fault is with glooped up reed block....................

................... this bike has to bloody start!

"Easy Start", I did see that mentioned in another post. I wasn't sure what you all called it in the UK. In the US we call starting fluid or some old timers call it ether.

http://www.google.co.uk/url?sa=t&rct=j&q=start%20you%20*******&source=web&cd=1&cad=rja&ved=0CDEQtwIwAA&url=http%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DcY1YndLmbXQ&ei=6YIeUaGRNqmC4gSX3IHIBQ&usg=AFQjCNH_qi_ucrUXgnCc3ZJWPVBxMnwKIA&bvm=bv.42553238,d.bGE

You say you turned the bike upside down and "a fair bit of fuel came out."

Just to be clear, there will be fuel that comes from the carb bowl. That is not a problem, it is just the bowl draining.

If the fuel poured out of the sparkplug hole, it came from the crankcase and will give a very rich air-fuel mixture that will not burn (flooded). This usually happpens when the float in the carb sticks and excess fuel flows through the carb, down past the reeds into the crankcase. Simply pouring the fuel out is not enough - there is still a very over-rich condition that will just make your plug wet so it will not fire. You need to clear out the excess fuel

Here is what i would do.

1) Turn off the gas at the fuel tank.

2) Remove the sparkplug

3) Put a rag over the spark plug hole I usually tie it in place because any liquid fuel still in the case will shoot up in your face with the next 2 steps.

4) Hold the throttle wide open to get max airflow.

5) Do this outdoors. Kick the bike over and over to clear out the fuel and excess vapors. 20 or so good kicks should clear it.

6) Remove the rag and kick is some more. If you are seeing visible vapor, it is still clearing the excess gas. If you hold your hand above the spark plug hole and kick 2 or 3 times, your hand should NOT be getting wet with fuel.

7) Install the plug and connector. Hold the throttle wide open and kick it a few times. It should pop and run poorly until the remaining excess fuel burns off. It will gradually clear out. Once it is running, turn the fuel back on at the tank.

If it does not start, pull the plug. If it is wet, there is still too much fuel or a really weak spark. Repeat the above process until the bike starts or the plug comes up dry.

Good luck and keep us updated.

Forgot to add, stripped and checked reeds. All ok!

I have sprayed brake cleaner in the plug hole and tried kicking over (highly flammable) same as easy start? Doesn't even try to start? S maybe a weak spark? How would I go about this?

The carb was off when I turned it upside down as I have stripped carb again (all ok btw) fuel come out of the spark plug hole and pushed kickstart with hand to get any out. Done plenty of kicks to dry it out with no plug too..

I'm now away for up too 7 days so going to have to think on it.

Wish I could spend more time trying to spray into spark plug hole to see if spark is too weak.

What would be the next thing with a weak spark? Coil pack?

Possibly the stator. If you watch the 92/93 Gas Gas model video on youtube by Jim Snell he discusses that this is a common problem and the coil on the stator may need rewound. They have a tech page on how to test for it.

Edited February 15, 201313 yr by coop650

Check the stator and HT lead then. Although your spark appears ok when out and against the frame the spark is only under atmospheric pressure, when under compression the stator may not be producing the power to allow the spark to jump the gap. Like coop650 said I'd watch the vids on YouTube and check the stator windings, I find it hard to believe that the bike is still flooded after all your effort. Let us know how you get on.

Thanks alot.

Once I'm back home I will give it a look

All th best.

Jamie

Clean up your earths on the coil and frame as its stood for so long

I will try that, looks like bad weather Wednesday onwards so should have some time off.

Don't suppose you know where they are located? I had a quick look. There is one that goes through a little box and bolts onto body (actually hold the box in place)

Starting fluids

I would be cautious about using too much starting ether or brake cleaner. Remember, a 2 stroke engine is lubricated by the oil in the premix. Solvents will remove the oil from the moving parts and bad things can happen. Better to simply dribble a little premix into the spark plug hole and try to start it.

Questions:

1.You are using new, fresh fuel, right?

2. When you turned the bike over and liquid came from the spark plug hole, are you sure it was gas?

Could it have been water? From your pics, the rear fender was off when you picked it up. Is it possible that rain water had collected and gone into the airbox, carb and into the crankcase? You said you drained all the fluids 7 years ago but yet there was “goo” in the carb. Normally carbs left dry get a white powder inside, if they get wet, they grow “goo.” If there is water in the crankcase, it will kill any spark and the bike will not fire.

I would remove the spark plug and carb (leave the reed block and intake boot attached to the engine) and kick it as I previously described. Then, with the carb still removed, install the plug, kick it over a few times and look at the plug again. It should be dry. If it is wet, smell it to see if it is gas or water. With the carb removed, you are basically moving air through an air pump. There should be no way for liquid to get to the plug.

If the plug is dry, dribble a little premix in the spark plug hole, install the plug and wire (with the carb still removed) and kick it a few times. If you get no start or popping like it is trying to start, you can be 99% sure it is an electrical problem.

More later on electrics.

Starting fluids

I would be cautious about using too much starting ether or brake cleaner. Remember, a 2 stroke engine is lubricated by the oil in the premix. Solvents will remove the oil from the moving parts and bad things can happen. Better to simply dribble a little premix into the spark plug hole and try to start it.

Questions:

1.You are using new, fresh fuel, right?

2. When you turned the bike over and liquid came from the spark plug hole, are you sure it was gas?

Could it have been water? From your pics, the rear fender was off when you picked it up. Is it possible that rain water had collected and gone into the airbox, carb and into the crankcase? You said you drained all the fluids 7 years ago but yet there was “goo” in the carb. Normally carbs left dry get a white powder inside, if they get wet, they grow “goo.” If there is water in the crankcase, it will kill any spark and the bike will not fire.

I would remove the spark plug and carb (leave the reed block and intake boot attached to the engine) and kick it as I previously described. Then, with the carb still removed, install the plug, kick it over a few times and look at the plug again. It should be dry. If it is wet, smell it to see if it is gas or water. With the carb removed, you are basically moving air through an air pump. There should be no way for liquid to get to the plug.

If the plug is dry, dribble a little premix in the spark plug hole, install the plug and wire (with the carb still removed) and kick it a few times. If you get no start or popping like it is trying to start, you can be 99% sure it is an electrical problem.

More later on electrics.

well said

Electrics

Most of the electrics are right above the radiator, jammed into a small space under the fuel tank cover. Before you start disconnecting things, take pictures and good notes so you can get it back together correctly. I often use painters tape and make small flags for each wire, writing numbers on the tape and making a drawing showing which number wire goes where - before and while I am taking it apart.

Testing

I was not able to view the video of your spark plug. I would remove the plug, reattach the high voltage lead, hold the body of the plug against the head and kick the bike over. Look for a good strong spark. You could also, bend the electrode to increase the gap to about .085” or 2mm and try again. A strong spark should jump that gap as well. Or it may jump through your body and light up your life! You may want to hold the plug with insulated pliers – especially if you wear a pace-maker.

I think the videos referenced by others above show you how to test resistance of the stator with an ohm meter.

Cleaning connections

FYI, my reference is my ’94 JT25 so it may not be exactly like yours. What I know is, mine has a jumble of wires in a small space. There is wiring for the spark, for lights and for the fan all in there. There are 2 small boxes; silver one is voltage regulator for lights and fan, black one is spark box. Be gentle as you dig in so that you only disconnect one thing at a time.

Clean any metal parts with emery cloth or a fingernail file until the metal is shiny. You might even want to replace any old screws, nuts and washers with new. Clean the frame where the parts mount to ensure good ground (earths). I like to gently squeeze any slip-on connectors before installing to ensure a tight connection.

Check the kill switch to be sure it is working correctly and the wires are not pinched or shorted to ground somewhere.

Check the connection at the rubber cap that clips on the top of the plug. I have seen those badly corroded and even with most of the wires broken right at the cap if people pull the wire, not the cap. If in doubt, replace it.

The stator (windings that generate the voltage) is located on the left side of the engine. To access that, you need to remove the shift lever, stator cover and flywheel. The flywheel requires a special puller. You can easily remove the plastic cover to look for signs of water – rust on the flywheel, etc. If it is clean inside, OK, if there is rust, you will probably want to remove the flywheel so you can access the stator to clean all the connections and ground screws.

With a good hot spark and gas, the bike should at least start. 2 strokes are pretty simple design.

Let us know how it works out.