ok sorry to hear of your bad luck with it mate,its hard to say sometimes without hearing the bike or even riding it myself but this could be a problem with the exhaust it may have a blockage and thos is causing the poor running and also stopping it from starting,just try undoing the exhaust at the barrle where it mounts on the taper fitting part enough for it to blow a bit it will be a little bit noisy but this will tell you if this is the problem if it goes better(or even starts).the crank seals can cause a problem as m says but it usually a problem with the bike revving that they give if they or one leaks ,if its a seal it will usually start but not rev much above tickover speed the same goes for the reed valve as they need this crankcase pressure to transfer the new fuel /air mixture up the transfer ports.
adam bike doctor
May 2010
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