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NO START CRF 450

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I HAVE A 2002 CRF 450. IT HAS NO IGNITION SPARK WHEN YOU KICK IT. IF PUSH START IT, IT WILL START AND RUN FINE. I DID TRY ANOTHER IGNITION COIL BUT STILL NO SPARK. I DO HAVE A LAB SCOPE SO I CAN CHECK FOR A WAVE FORM FROM THE MAGNETO OR CHECK OHMS, BUT I DONT HAVE ANY SPECS OR WIRING DIAGRAM. IM THINKING WHEN I PUSH START IT, THE MAGNETO SPINS FAST ENOUGH TO PRODUCE A SIGNAL. IS THERE ANY THING THEY ARE NOTORIOUS FOR? ANY HELP WOULD BE GRATEFUL, THIS THING IS TANK TO PUSH START. :cry:

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If it starts by push starting it then it has spark. I am not being a smart ass but did you properly check for spark? My 2002 went from starting one ride to kicking 150 times and not starting the next ride unless I push started it. Valve adj or KW valves now and two twist of the throttle and one kick. I think it runs better then when I bought it.

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YES, I NOTICED THE COMPRESSION WAS GETTING WEAK SO I PULLED THE VALVE COVER AND BOTH INTAKES WERE RIGHT AT ZERO. I ADJUSTED THEM AND THE COMPRESSION WAS BACK UP, BUT STILL NO START. I DID THE OLE LAY THE SPARK PLUG UP AND GROUNDED IT AND NO SPARK. I TURNED OFF THE GARAGE LIGHTS AND NO SPARK. I MUSTERED UP THE COURAGE AND HELD THE SPARK PLUG AND NO SPARK. I SPRAYED FLAMABLE SILICONE SPRAY (DUMB I KNOW) ON THE TIP AS I KICKED IT AND NO SPARK OR FLAME. WHEN I PUSH IT, IT FIRES RIGHT UP PULLS LIKE A TEAM OF MULES. I DO UNDERSTAND WHAT YOUR SAYING ABOUT COMPRESSION, BUT IT SHOULD NOT KILL THE SPARK. ONCE I ADJUSTED THE VALVES, IT WAS BACK TO PRETTY HARD TO KICK OVER, BUT STILL NO START.

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You have a compression problem, usually when it won't kick start, that's what it is! Try a brand new spark plug, and have a friend ground the sparkplug on the aluminum frame. Kick it hard and fast, and you will see spark. That's all it needs, valve problem for sure especially if it's not starting!

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YES, IM GOING TO THE TRACK THIS MORNING (SAT) AND SWAP THE "BLACK BOX" WITH A FRIEND. THE MAGNETO AINT QUITE SO EASY, BUT IM GOING TO HAVE TO DO IT. THANKS

MONTY SALYER #045

REESE SALYER #746

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CAP LOCKS ARE THE EQUIVALENT TO SHOUTING!!! :cry:

...let's use our indoor voice. :cry:

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THANKS SPINYARD,

I WAS SHOCKED AT ALL THE POSTS ABOUT VALVE PROBLEMS. I DID ADJUST THE VALVES AND THE COMPRESSION IS BACK UP. AS OF RIGHT NOW IM GONNA SAY THERE IS NO SPARK. I DID GROUND A NEW PLUG AND I REMOVED THE OLD ONE SO I COULD KICK IT FASTER BUT THERE IS NO SPARK AT THE TIP. I KNOW LOW COMPRESSION WILL MAKE IT HARD TO START, BUT EVEN IF I TOOK OFF THE HEAD AND PISTON, WHEN THAT MAG SPINS THERE SHOULD BE SPARK. BEFORE I ADJUSTED THE VALVES IT WAS GETTING VERY EASY TO KICK IT OVER. AFTER I ADJUSTED THE VLAVES IT WAS BACK TO PRETTY STOUT TO KICK OVER. EVEN THOUGH IT FELT STOUT AND NORMAL I DID A COMPRESSION CHECK. IT HAD 75PSI KICKING IT OVER. THATS WITH THE COMPRESSION RELIEF ARM ACTIVATING THE EXHASUT VALVES DURING COMPRESSION STROKE. I DONT HAVE ANY SPECS SO IM NOT SURE IF THATS NORMAL, BUT I STILL HAVE NO SPARK. :cry:

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Sorry Dovii, I'm the quitest person you ever met, i use caps so i can see what I'm typing, plus all four of my kids are teenagers and this key board rolled snake eyes years ago. I will make the effort.

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No problem. That's much better (easier on the eyes). I really would've replied to anyone. I just need my 100th post to become... TT Bronze Member Man!!! :cry: :cry: :cry: :cry:

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Well no news is good news. I went to the track sat morning and of cousre I had to push start it. I stalled it in a corner during practice and was pushing it to a table top so I could restart it and another 450 rider came over and said he wanted to try it. He started it on the fisrt kick. Then 2 more times in a row. The fourth time it would'nt start. I went ahead and raced it on Sunday and won both moto's. It will do this intermittently, start one time then not the next, but mostly it wont. As of right now Im pretty sure there is no spark when it wont kick start. A friend of mine has a manual with all the specs for mag, coil and cdi. I will update once I figure out that i dont have any idea what Im doing.

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This may sound silly but check your kill switch and make sure it isn't grounding to the frame at times. I had a bike that would stall and be hard to start. Turns out everytime I turned left the kill wires would pull snug and reveal copper from under the insulation. After replacing everything in the ignition system only to have it happen again. Now I start with the simple things first. Next would be the plug cap. You may have a break in the wire and push starting creates enough of a jolt to jump the gap.

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I did unplug it, but I did not open up the harness for a complete visual. I am gonna go ahead and borrow a repair manual from a friend so I will have everything I need at hand. Thanks, I like the user name "sirlimpsalot" I can relate.

Monty Salyer #045

Reese Salyer #746 aka "Chicken Lips"

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I'm having a similar problem. The bike would have spark then it would not.Then it would only spark every 2nd or 3rd kick. Now there is no spark at all. I did a resistance test on the ignition coil. Secondary windings were fine(spark plug lead). Primary reading was all over the place. Readings would be real low then on recheck they would bounce from high to low. I rechecked it a few times and now I am getting 0 ohms , once in a while it will bounce to .1 or .2 .

It was hit and miss for a while , sometimes it would fire others not . It's dead now, hopefully it's just the coil.

Also check the resistance on your stator coils.

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