Lightning problems Yamaha XT 225

My motorcycle does not turn on easily, I have reviewed the carburement system, air filter and are without novelty, when checking the spark plug and starting I notice that the spark it generates is not "strong" but that it is scarcely noticed. Could someone tell me that I should review to correct this problem? THANK YOU.

hello.
Look in the coil, it is fucking with a screw to the chassis sacal it and sand it, to be in 1 place a little oxide, but it is already the subject of the CDI and it does not carry of the magnetic dish, good luck !!!!