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how does this spark plug look? (PICS)


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Why are you asking? Is your bike not running correctly? Plug looks good.

well yeah the bike runs good.. sometimes.

sometimes it starts fine when hot, sometimes it doesnt. it starts cold everytime, but after riding it and stalling or dropping the bike (rare:busted:), it just doesnt want to start, but will bomb start down a hill.

Ive been told it might be the idle screw and or/fuel screw so I will check that out next time I am riding..but if you have any suggestions I am more than happy to try them.

jd jet kit

stage 2 cam

pretty sure im jetted properly by look of spark plug, it is new BTW.. has about 8 hours on it.

whole new engine with 8 hours on it. piston, rings, top end, SS valves. I got bigborethumpers stage 3 bolt on kit with the SS intakes. theyre still in perfect spec.

decompression gap is .28

I just cant figure it out 👍

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If you ride the bike for 15 min, then let your bike idle or start it three more times you wont get a correct plug read. The plug should be new. The fuel screw could be off by a hair a cause it to run rich.

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I have just been recently re-schooled about the whole plug color/ jetting thing. Eddies quote " tuning by plug color will just have you chasing your tail!

the 08 is rich even at sea level stock. they were way off the mark main jet wise.

a 4 stroke that is lean enough to hurt itself runs so bad its obvious."

He also told me a correctly jetted 4-strokes plug will look as white as a new one.

Read this post.> https://thumpertalk.com/forum/showthread.php?t=884863

There's a moral to this story.

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hm. thanks for the help guys, thats interesteing info and I appreciate it.

I dont think I can ever get jetting perfect as I ride in the mountains and my elevation can change up to 2000 feet some days... 👍

that EFI is looking good right about now! I just wish my bike didnt have those damn starting problems!

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I'm no expert, but the plug looks a tad bit rich.

This is a long shot, but I had a similar problem with an 04 CRF450. It turned out that the tiny o-ring on the pilot screw had split. It was murder to cold start, but fired right up hot. It took a complete carb disassembly to find the problem.

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I'm no expert, but the plug looks a tad bit rich.

This is a long shot, but I had a similar problem with an 04 CRF450. It turned out that the tiny o-ring on the pilot screw had split. It was murder to cold start, but fired right up hot. It took a complete carb disassembly to find the problem.

mines the opposite, starts first kick when cold. but when its hot, sometimes it starts first kick, sometimes it takes 25+

it also seems to be worse when I stall it in gear (cant find neutral:foul:) or drop the bike, which I dont do often, but sometimes you cant help it when youre on the side of a hill, cant find neutral, and all of a sudden she stalls on you and you fall downhill 👍

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When a bike gets hotter it will run richer

It will act richer....

if youre trying to read plugs with pump gas, its a waste of time. Its so inconsistent and loaded with crap like remnant diesel, water, milk and who knows what else you cant use plug color.

If you got some good "race fuel" that was correct spec (95-98mor)for what you're doing its a hell of a lot easier to tell where your at. But even then, all you can do is read the WOT color. Once you close the throttle, your reading pretty much goes out the window. After you get the main jet dialed, you've gotta feel your way through the rest of the needle and pilot settings.

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