Yz250f hard to kick help!

Alright, first time posting on here so about a month ago I bought a 2003 yz250f with "a bad head gasket", he showed me the oil he drained from it there was coolant in it so it made sense he said he was riding it and it started shooting coolant out of the overflow and smoking so I bought the bike for 400$. When ive went riding with him it has always ran really good, So I ordered a cometic top end gasket kit I tore down the engine and piston, rings, and the cylinder wall all looked good so I didn't replace any of that Also the head gasket looked good and I took the head to my uncles machine shop and had it milled down its withing .002" everything in the engine looked good to me although im not a mechanic! So I put everything back together and replaced the coolant cap oil filter and it wont start, its really hard to kick. timing is perfect I did a quick valve measurement .08mm I think it was. so I don't know why it wont start it has fuel spark and compression to my knowledge any help would be appreciated thanks!

Ok, by really hard to kick, do you mean its hard to physically KICK over...or it just doesnt want to start easily. Sometimes the way things are worded when they are posted adds confusion to what the problem even is.

Edited by J_WR2fitty

like physically hard to kick it doesnt seem like the engine moves more than 1 revolution after the kick and its super hard to push down

Your timing off? Or the bottom end could have locked up my kx250f has had a bottom end seizure before with no top end damage too

Just had a ktm 2-stroke do same thing.

Bottom end crank bearing siezed.


thats what im thinking im taking it to a guy sometime next week i really dont wanna put another 3 or 4 hundred in it but i guess itll be my winter project. :thumbsdn:

for giggles. loosen up the cam caps and see if that makes it easier to kick.

Cam cap tightening torque is only 7 lb/ft. You can almost tighten to that torque with your fingers. It's very easy to over tighten and cause the cam to bind.

I just tried it with the cam caps it does kick a little easier it feels about right to me but it wont start still it doesn't sound like its firing even though I checked the plug and its sparking

.08 Is a lil tight. Also check to make sure your auto decomp on your exhaust cam is working as it should.

alright ill check them again tonight and also the hot start plunger is stripped out would that make a difference i put some gasket sealer on and zip tied it tight till i get a new cable.

alright ill check them again tonight and also the hot start plunger is stripped out would that make a difference i put some gasket sealer on and zip tied it tight till i get a new cable.

The hot start wouldn't make it hard to kick. It would make it harder to start however.

i finally took it to a mechanic ill get it back sometime next week hopefully

The guy cant find whats wrong with it and hes had 2 other people over to look at it maybe the cdi box? the engine is put together perfectly valves timing bottom end etc. and its getting fuel its sparking but maybe the wrong time or something? i dont know i just wanna ride!

Edited by Batman77

did you dispose of all the old gas in the tank? I mean all of it and not just put fresh gas in the tank on top of old gas?

What most people don't realize is that with the new ethanol gasoline, the water molecules are absorbed into the alcohol and the alcohol doesn't let the water separate. So where the old gas formula, when full of water, use to show a separation like oil/vinegar, the new ethanol blends look like normal gas but no separation. worse yet, the watered gas settles to the bottom and is the 1st thing into your motor.

Okay im wondering is there a way to check the bottom end if anythings bad or do I have to split the cases? also the rings are good and its not sparking consistently put a new cdi box in and it doesn't sound like its doing anything AT ALL when I kick it over. its really making me wonder now ive had the bike for 2 and a half months and cant figure out whats wrong with it.

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