Sparks Jumping Around Electrode

YetiWoodz

Active Member
Joined
Dec 19, 2019
Messages
696
After trying and failing to get my bike to start after a few runs...I decided to test my spark plug. And the sparks are not consistently in the same spot, its like its circling around the electrode like in this video. Is this normal, if not , why? Btw, the sparks are blue.

 
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YetiWoodz

Active Member
Joined
Dec 19, 2019
Messages
696
Your engine is too rich, plug is firing fine.
I have a #62 jet in and running 40:1 and my bike was running ok before, hard to start, but was running strong. I didn't run it for a month though. Maybe oil settled or something.
 

mony0_3

Member
Joined
Jan 18, 2020
Messages
65
Better pull head and check cylinder for scratches. I just pulled mine and a wrist pin e-clip broke and scarred the piston and cylinder.
 

YetiWoodz

Active Member
Joined
Dec 19, 2019
Messages
696
I might have a compression problem come to think of it. Its been really hard to start after putting on the new cylinder, head, and gaskets. Also, when I let go of the clutch, there is a lot of resistance against moving the back tire, but just slightly less resistance than with the stock stuff on. With the stock, I couldn't roll the back tire at all, it was locked. Now, I can roll it, but its hard too. Is that an indication of not enough compression?
 

Chainlube

Well-Known Member
Joined
Jan 5, 2020
Messages
1,660
What did you do before you installed the new stuff, do any prep work? Take any pictures of the process?
 

YetiWoodz

Active Member
Joined
Dec 19, 2019
Messages
696
I did a lot of prep work and I took my time doing it. I cleaned up the ports, chamfered the edges, redirected transfer ports' flow towards intake, port matched, transfer feed match, tested and adjusted squish band to .8mm. I have a 5.5cc authentic Fred Head on, g5 steel wall cylinder, copper head gasket, single fabric base gasket. Torqued head nuts evenly and at 12 ft lbs and with blue loctite. I did take the head off a few times due to primarily the squish test, so the copper gasket was reused about 5-6 times. I'm not sure how much to torque the spark plug.
98065
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98068
 
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