Motorcycle Repair: 1984 honda XL250 timing problem?, honda xl250, exhaust stroke

Question
hey i just bought a 1984 xl250r that was said that the timing might be off and that the timing chain needed to be replaced. I replaced the the timing chain i made sure the motor was on tdc, i made sure the cam was on tdc. the carbs are clean and i am getting spark but the bike will not start. if i spray starting fluid the bike will shoot flames out of the carbs which makes me think the timing is off... im thinking its sparking on the exhaust stroke? how would i   fix the timing problem, what is a good way to make sure the spark timing is correct and also correct with the valve timing. Any help would be great!

Answer
Aaron,try a couple things first. Pull the spark plug,turn over the engine over till the piston is at TDC. Feel the top of the piston with a small screwdriver or wire to ensure its at the top most portion of its stroke then check the timing mark in the window on the flywheel. Now check the cam.Usually the cam has three marks on it. Two are directly accross from each other and align along the top of the head with the timing dot at the top of the cam gear.Also check the valve lash clearance,try about .004 on the intake and about .006 on the exhaust. Install a fresh spark plug and try one number lower on the plug as this will be one step hotter. Example the bike has a DR8ES go to a DR7ES. Try this first to see if it will help.