650/X-2 Dead solider

[Antisapation]

Bought a good compression 89 650 sx.
Has primerremoved choke, good blue spark, timing screw in center of adjustment loop. New stock flywheel, new stator, new dual coil with lines(spendy one), good 42mm carb, new plugs, checked case for excessive fuel, not much found. I've had my head in this ski for three weeks, never got to ride it, I have five, and I'm not to bad at getting around a two stroke, but this one wont even pop, even with a squirt of starting fluid )wich I stay away from.
Not even a pop ! I'm stumped.
My old Husky will pop without a carb on it and bad rings, I dont get it ???
Please someone shed some light on my nightmare purchase. I just dont see why even if timings off why it wont even pop once ?????
My eyes burn from reading so much and I still haven't found a similar situation frickin anywhere.

 

[wmazz]

Couple of thoughts:
Is it loaded up, it sounds like you found some excess fuel.
What is the condition of the reeds?

Very strange that it needed a new flywheel, why was it replaced and did
it run with the new flywheel? Why did he sell it.

The crank case drains, are they blocked off?


Bill M.

 

[Antisapation]

Couple of thoughts:
Is it loaded up, it sounds like you found some excess fuel.
What is the condition of the reeds?

Very strange that it needed a new flywheel, why was it replaced and did
it run with the new flywheel? Why did he sell it.

The crank case drains, are they blocked off?


Bill M.

Hi, it ran for the guy I bought from but it started hard in his truck. When I got home it started ,when I went to lake to take the first rip, it started once and died, then that was it. When I was later trying to figure out why, I suddenly had no spark when I checked, then I looked in peep hole in flywheel case and saw a copper wire. Took apart and found screw backed out of charge coil and dropped into flywheel magnets. Bird nested big time and locked up into flywheel. Also cracking all the magnets.
So I replaced it all with new stator and flywheel. Also new double coil and wires and boots, new plugs, got a great blue snap, plugs are ngk7es, with .029" gap.
Reeds look almost new, nice and clean no chips, gaskets all new. Equal good compression. It should fire at least once ? Nope !
I've tried every scenario and steps to start it, even starting fluid for a second.
Nothin ,not even smoke.
Even if carb was out of whack it would still fire. And the little fuel I sucked out of case wasnt enough to stop it from breathing, I think.. I'm stumped like I said. I grew up on two stroke dirt bikes, and hill climbing, usually when spark air and gas meet it goes pop. Not this poor thing. It's got a cancer I dont reconize.
Tell me you have a new idea ????
I appreciate any input, thankyou

 

[wmazz]

And the little fuel I sucked out of case wasnt enough to stop it from breathing,

2 thoughts. I prefer the easy ones first.

Flooded. Ignition will only occur within a narrow range. Pinch off the fuel line
or remove it from the tank, and hold the throttle wide open, check the spark
plugs often.

Keihins are famous hard starters. Most of the time the needle and seat refuses
to open and appears to have a fuel pump issue. On any carb if the needle and
seat is leaking, it is going to load up.

It is common for people to remove chokes and install a primer when the engine
is hard starting. But the blue Sudco 42mm Keihin didn't have a choke.

Second thought. The woodruff key was pushed out of the crank shaft when
you installed the flywheel. I don't like recommending to remove the flywheel
again, but 650 woodruff keys will easily slide out of place and stick to a magnet.

When you reinstall the flywheel, the flywheel must be firmly seated and properly
torqued to prevent future problems.

650 compression is 165psi with a Snap-On compression tester.


Bill M.

 

[john zigler]

I am guessing you have an ignition issue.... (Weak spark)

How are you testing spark? You can not accurately test spark by just laying the plugs on the head. Weak spark will go away under load. Load = compression. You need to test with spark testers.

Also .029" plug gap is too much, try tightening it up to about .022"

 

[joeschuit]

You can verify the timing by turning it over with the flywheel cover removed and using a timing light. I had a 550sx that had compression, fuel, and spark but wouldn't start. An aftermarket stator coil was installed and the timing was 90 degrees off.

 

[Antisapation]

Couple of thoughts:
Is it loaded up, it sounds like you found some excess fuel.
What is the condition of the reeds?

Very strange that it needed a new flywheel, why was it replaced and did
it run with the new flywheel? Why did he sell it.

The crank case drains, are they blocked off?


Bill M.

I checked with my scope. There is a block plate already on . I was hoping for something screwed up. But nooo

 

[Antisapation]

You can verify the timing by turning it over with the flywheel cover removed and using a timing light. I had a 550sx that had compression, fuel, and spark but wouldn't start. An aftermarket stator coil was installed and the timing was 90 degrees off.

I'm wondering the same thing. I saw when ordering a new flywheel and stator that 2 out of the 100 pics I looked at there were two flywheels that the key lined up with a front thread hole on right side of bolt hole. The rest of them like the one I had before Is on the left of it.
I'd guess after marking on paper ,it would be about a 20 degree difference.
That would do it, right ? I'm reaching ,but poop, I'm getting grey hairs.

 

[Antisapation]

I'm wondering the same thing. I saw when ordering a new flywheel and stator that 2 out of the 100 pics I looked at there were two flywheels that the key lined up with a front thread hole on right side of bolt hole. The rest of them like the one I had before Is on the left of it.
I'd guess after marking on paper ,it would be about a 20 degree difference.
That would do it, right ? I'm reaching ,but poop, I'm getting grey hairs.

Also, I have to have cover on for starter nipple. I have peep hole though.

 

[Antisapation]

Also, I have to have cover on for starter nipple. I have peep hole though.

How many types of models using this block did they make. Is there really another flywheel and setting mark ?
That would be a KTM move, poop heads cant keep a design clean for more than a week.

 

[Antisapation]

I am guessing you have an ignition issue.... (Weak spark)

How are you testing spark? You can not accurately test spark by just laying the plugs on the head. Weak spark will go away under load. Load = compression. You need to test with spark testers.

Also .029" plug gap is too much, try tightening it up to about .022"

Ah yes, the spark tester, im on my way to the store to get one. I agree ,I think the spark is dead under compression.
Or my fly and mag are way off. Wrong ones maybe ? Cause even way off I should get a pop or smoke ?
Well, I'm getting a timing light too, thanks to my kid, I no longer own one I guess. I wonder if I could trade him in for a running ski ? I'd like a 750 please.

 

[joeschuit]

With the spark plugs out(grounded of course) you can turn the motor over using a drill on the flywheel nut. There should be little resistance and be able to spin fast enough to spark. I also find my own tdc and put some tape on the flywheel to mark tcd and around 20 degrees btdc. That way you're verifying the actual timing, not what the flywheel or block markings may say.

 

[Antisapation]

2 thoughts. I prefer the easy ones first.

Flooded. Ignition will only occur within a narrow range. Pinch off the fuel line
or remove it from the tank, and hold the throttle wide open, check the spark
plugs often.

Keihins are famous hard starters. Most of the time the needle and seat refuses
to open and appears to have a fuel pump issue. On any carb if the needle and
seat is leaking, it is going to load up.

It is common for people to remove chokes and install a primer when the engine
is hard starting. But the blue Sudco 42mm Keihin didn't have a choke.

Second thought. The woodruff key was pushed out of the crank shaft when
you installed the flywheel. I don't like recommending to remove the flywheel
again, but 650 woodruff keys will easily slide out of place and stick to a magnet.

When you reinstall the flywheel, the flywheel must be firmly seated and properly
torqued to prevent future problems.

650 compression is 165psi with a Snap-On compression tester.


Bill M.

I've dis and re assembled this machine so many times, that it only takes less than five minutes to strip. I should try out for nascar... I keep close eye on my key ways and keys. I learned that lesson way long time ago.

 

[Antisapation]

With the spark plugs out(grounded of course) you can turn the motor over using a drill on the flywheel nut. There should be little resistance and be able to spin fast enough to spark. I also find my own tdc and put some tape on the flywheel to mark tcd and around 20 degrees btdc. That way you're verifying the actual timing, not what the flywheel or block markings may say.

Thankyou, good idea getting around the starter, daa, I sometimes I can amaze myself at the lack of intelligence I have some times. I've been breathing gas fumes for three weeks, I need a couple second head start possibly.

 

[Antisapation]

Thankyou, good idea getting around the starter, daa, I sometimes I can amaze myself at the lack of intelligence I have some times. I've been breathing gas fumes for three weeks, I need a couple second head start possibly.

Hey, are these 650s that sticky precise on the timing ? My ford 302 doesnt care where the distributor is pointing, still starts ......

 

[joeschuit]

Not sure what the 650 cdi has for a curve, but if the initial timing is between 5-35 degrees btdc, it should fire and run.

 

[Antisapation]

I went and got a adjustable spark tester and a digital timing light that way it shows me what degree it is if it works like I think it should. Thanks for the input, I'll see what I get out of these tools.

 

[Antisapation]

Cant find an answer to what do you set spark plug load tester to ? And I got wrong inova timing light , I'll get the right one, this one makes it look like I'm 180 off.
Ugg !
I set the gap at about 20 and it looks weaker than when plugs out and grounded. If unplugged plug is in it's a ok spark, when it's out it's a big blue spark.
Weird stuff, the plug ain't hooked up and it makes a difference. Strange. Does this change when I get my timing right ? To better ? Or did I spent alot of money on a crappy ignition coil ? This thing is cursed