Hot start cable broke on yzf 250

SOURCE: 1997 yamaha yzf 600r electrical problems

a jump box is nothing more then a battery with leads on it so where are you connecting it verses the new battery you put in the bike. that doesn't make since unless you are connecting the box right to the starter motor then it be constently running the motor untill you unhooked it. check all your fuses and examine all wire harnesses for damage, burns, or any mellting.

SOURCE: yzf 250 wont run without the choke

Hi mikelapt
You will have a carby problem. When the choke is one, and different fuel circuit is used. When you turn off the choke, you go back to the idle circuit of the carb is used, when under throttle, main jets kick in. You probably have a blockage in one of these circuits. Strip the carb down, clean with carby cleaner, blow out all air circuits and jets with compressed air, then setup the idle mixture and tick over speed. Always work with fresh fuel, and drain off, discard any fuel older than a couple of months. It goes off, and turns to a gel  like substance that blocks up your carby. Hope this has explained your problem. Happy to talk to you more about it. A FixYa vote is a great reward for for my time taken to explain this to you. Cheers
regards robotek

SOURCE: rebuild a yzf 250

try this
http://www.mxguy.com/motorcycle-maintenance/2003-yamaha-yz250f-service-manual_01-16-2008/

SOURCE: 97 YAMAHA YZF 1000,wont start itself after bike is warm

Have you checked the ground lead?

Make sure it is clean, it runs down and bolts to the top right hand side of the crank case.

Sometimes what happens is, that lead gets grime on it, oil or corrosion.. and it doesn't make good contact. The lights, spark ETC load the crank case and frame full of DC.. when you shut the bike off the dc cant flow through the starter so it won't turn over.

after a while the dc trickles out it will let the bike start again.

Hope thats it and it works for you, good luck!!

P.S. how is he liking his ace?? Awsome bike, I have had mine since 1999, and it not about to go anywhere!!

SOURCE: 2005 YZF 250 were is the oil sc\trainer locaded?

The drain plug is at the bottom left corner of the center case. The oil filter is on the left case cover.

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