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Hot start problem, 08 250 Sx-f

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I am having a goofy hot start problem. Most of the time it is very hard to start but sometimes it seems to start fine. My hot start lever is working fine because it leans out when pulled while already started. I bought a JD kit and have it in hand ready to install but wanted to check my valves first.

The specs are:

Intake - .1mm to .2mm

Exhaust - .12mm to 2.2mm

The readings are:

Intake - .004" = .1016mm

Exhaust - .006" = .1524mm

The intakes are on the tight side of the spec. I have talked to a few people who like there valves mid to loose in spec. Would it be in my best interest to get a little more clearance in there, and then jet the bike? I also have a full Dep System 7 exhaust and haven't opened the carb yet (bike is used) so I don't know if the bike has been jetted for the pipe yet. I wanted to start with the valves if they should be adjusted.

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Sometimes on mine, if I hold the throttle about 1/4 open (steady) don't keep twisting it and pull the hot start it fires right up. Worth a try.

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Okay so I have an update. I first loosened the valves a couple shim sizes on the intake, and a single shim size on the exhaust. I rode it and it was still doing the same thing. :ride: The last ride I noticed some bog or sputter at random intervals.

I installed the JD kit and found (again, purchased used) the bike already had the main jet changed to the 180 I was going to install. Put in the main from the kit to be sure. It had a leak jet plug so I installed the leak jet from the kit. I am not sure if the needle was stock but installed the red needle in clip 5 from the kit (may switch to 4 after I ride it more). Started and ran great on a quick test ride, but once again same thing. Now it doesn't seem to be a hot start problem, just a starting problem in general. :ride:

The next day I tried to start it and kicked it at least 8 times with absolutely nothing. I put a spark checker on it and nothing. :D Kicked it more, and out of the blue got spark again. Kicked it more, and it would drop out again. I scoped the crank sensor and it looked great, spark or not. Stator was delivering voltage as well. Tested the white blue coil wire at the coil and it was dead. It seemed at first to be totally random. When I got it started I wiggled the harness coming out of the ignition module, and it would die. Wiggle again, kick it, and starts right up. I FINALLY found it :banana:. I replaced the harness with a new one, and now the bike runs and starts better than it ever has before. :D I just need to dial the fuel screw in to money town. I have a high idle after it is warm, and at rest. I lowered the idle screw but have yet to correctly determine if I have the right pilot as I had somewhere to be. I hope this helps someone else with a similar problem or when the problem first occurs! :thumbsup:

Edited by WrenchinJunk

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