Can any motor builder help?

Excaliburbmx
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Excaliburbmx
Edited Date/Time 11/3/2015 9:24pm
My wife has a kx250 and so do I. Actually we have three but they all start different. I was wondering if someone knew a way to build a motor to start easier?

Mine is pretty smooth hers is way harder to turn over. It was rebuilt by an amateur rebuilder and it just kicks really hard.

Any help would be appreciated.
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pete24
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pete24 11/2/2015 6:46am
11/2/2015 6:46am
are they 250fs? make sure the cam caps arent overtightened
Excaliburbmx
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Excaliburbmx 11/2/2015 6:48am
11/2/2015 6:48am
Kx250 2 stroke. Mine kicks smooth and nice hers turns hard both have been rebuilt by different people.

Spydee
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Spydee 11/2/2015 7:09am
11/2/2015 7:09am
What year are they?
colintrax
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colintrax 11/2/2015 8:12am
11/2/2015 8:12am
What's the compression on hers?

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jsmx97
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jsmx97 11/2/2015 10:06am
11/2/2015 10:06am
There are far too many variables to give you a direct answer to your question.

Are they the same year?

What engine components were replaced in each bike?

What brand parts were used?

Always a possibility something was install incorrectly by the engine builder... only real way to check would be to tear down and inspect
Excaliburbmx
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Excaliburbmx 11/2/2015 1:19pm
11/2/2015 1:19pm
Both 2000 both oem motors. Both wiesco pistons.
Belray 80w casesaver klotz 32:1 supertechniplate
very close in compression.
Premix
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Premix 11/2/2015 7:05pm
11/2/2015 7:05pm
Too many factors to say.
Phillip_Lamb
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Phillip_Lamb 11/3/2015 10:36am
11/3/2015 10:36am
you might just need to take it in to reputable shop or builder.
DTHA70
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DTHA70 11/3/2015 10:52am
11/3/2015 10:52am
have the same guy do them both with exactly the same parts at the same time. take away any variables. same head, carb, reeds, pistons (get the cylinders re-plated together by the same company), same cranks, EVERYTHING. and have the same guy assemble them both.
carl-h
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carl-h 11/3/2015 1:54pm
11/3/2015 1:54pm
Are you sure hers doesn't just have more compression?
Excaliburbmx
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Excaliburbmx 11/3/2015 2:17pm
11/3/2015 2:17pm
No they are close
Polishhammer 11/3/2015 6:08pm
11/3/2015 6:08pm
If the compression is very similar, I'd take off both flywheel covers. Put a socket on the flywheel nut and slowly turn both engines over in neutral and in gear. That takes the kicker mechanism out of the equation. If they turn the same in neutral, but say both are in 3 rd gear and now ones much harder it could be something in the trans. Just an idea.
Factor E
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Factor E 11/3/2015 9:24pm
11/3/2015 9:24pm
Take the plugs out and kick them over to feel the difference. Kick mechanism may be binding.

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