1990 sp not starting now.

[gixxerjohn750]

I have got a 1990 Sp and now it wont crank. It was sitting up for a while and i changed the fuel and added sea foam to it. It cranked up and ran fine in my driveway, so i took it to the lake. I cranked it in shallow water and it felt like something sucked up into it and got shot out, it backfired and then it cranked. it ran for about 5 minutes after that but would not go top speed.Eventually it died and would not crank again. I have changed the plugs, wires, the ignition coil, and sprayed starter fluid into it and nothing. it just turns over until the battery goes dead. Any help would be greatly appreciated. Thanks

 

[kustomkarl]

Whats the compression...
You'll need a compression tester. Go to Auto Zone. I think they sell for like $25.00. The compression gage, will screw in the cylinder head in place of the spark plugs. To test compression, remove both spark plugs. Place spark plug caps on the plug cap studs near the cylinder head to ground the empty caps. This completes the circuit of the ignition electrical system and prevents any electrical problems from the caps being un grounded. Using the correct adapter for the threaded end of the tester,( same length of the spark plug threads length)screw in the tester in one plug hole. Hold the throttle wide open. Push the start button. Watch the compression gauge, when it peaks out at the most compression, let go the start button. Read the psi number. I would do it 3 times to be sure it is accurate. Check both cylinders the same way. The ideal compression is 150 psi per cylinder. If it is less, it's not a problem as long as they are close to being the same. If the psi is less than 90 it might need be time for a tear down and a rebuild. If the psi in 1 cylinder is say 140 psi and the other is 80 psi you need to tear down and repair. This difference is a lot and there is a problem. I hope this helps you.

Karl

 

[gixxerjohn750]

OK ichecked the compression and 1 came out 140 and the other came out 136, so i am assuming this is ok. When i pull the sparkplugs and check them, i am not getting any fire. I have checked the stop switch and it is ok, i have checked the safety switch and it is ok, i have replaced the plugs, plug wires and ignition coil, but i do not know where to go from here. HELP.

 

[timmyboy76]

gixxer...(just sold my 97/600) anyway..last thing I'd suspect is the ignition coil off the stator. You can buy new, or find used stator assy off ebay....:good luck