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Starting a CR480 when cold

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I just picked a 480 in decent condition.  It had sat for about a year without being started.  I got it home, checked spark, compression and cleaned the carb really good. Everything looks to be in order.  I put it back together and kicked... it started first kick, idled for about 30 seconds and then died.  Now it wont start. I'm not sure what has changed. Still have loads of compression and good spark, so it has to be in the carb somewhere.  The guy who put it in storage did a good job getting it ready.  The tank was drained and the carb was drained.  All the jets are clear.  But when I kick it now and it wont start, so I pulled the plug and it isn't wet.  It looks as though the fuel isn't making it into the cyl and I'm not sure why. There is a small about of dripping coming out of the float bowl over flow so I know the float is not set at the right height.  Does any one know the correct spec for the float height or have any other ideas of what it could possibly be?  I have done a little searching and have found that these bikes have a reputation as being hard to start.  

 

Thanks.

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Take the plug out of the bottom of the carb and turn the fuel on to make sure fuel comes out

I took the plug and yes there is fuel coming out.  I know the float isn't quite right because fuel just barley drips from the over flow when the petcock is left on.  I tried the procedure for starting the bike and it wanted to start. I kicked probably 1000 times and a few times is was really close. I guess they are just finicky. 

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I did. Four times. I can slowly roll it back and forth in gear and hear/feel it turning over. But when I tried push starting it, when I would pop into gear it would lock up and skid to a stop.

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I did. Four times. I can slowly roll it back and forth in gear and hear/feel it turning over. But when I tried push starting it, when I would pop into gear it would lock up and skid to a stop.

What gear? Try a gear or 2 higher. I usually use 2nd/3rd

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i had a cr480 and i found a procedure online somewhere: choke it, hold throttle wide open and kick it over slowly 2 or 3 times, close throttle and kick it like you mean it. she usually fired right up.

she can kick back though huh?  :)

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Turn fuel on. Lean bike way over 'til fuel flows from the overflow. Stand up,mount and kick to be rewarded with glorious two stroke noise. Worked on my YZ465 for a couple decades now. Try it w/o the choke first.

Edited by T.RexRacing
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I'm doing all the things you guys are saying.  I guess it is just stubborn.  I'll try again tonight after work.  Thanks for all the input. 

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Have you set the float (22.5MM from what I found) yet? If yes and the overflow still leaks check the tube in the float bowl that controls overflow. I had one that cracked and split and dripped like you describe. had me setting the float way lean to try and make it stop.

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I haven't had a chance to play with it again yet due to working 12 hours a day. But maybe raising the needle will help the bike get the fuel it needs to start?

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How to start a 2 stroke Big Bore Motocross Bike:

I followed this instructional video and the bike started first kick. Woohoo!!!

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Well back to the drawing board. Went riding yesturday. .. luckily there was an extra bike I could ride because my bike started loosing spark and wouldn't start. Time to pull it back apart and start checking grounds and connections. Got to love an old bike :-)

Edited by VCHSS176

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Got it sorted out for the most part. The exhaust was plugged. Took the pipe off and got all the raw fuel out of the cylinder and she fired right up. Doing a little tuning tonight and cleaning out that pipe.

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