WallyWales

Well, we gapped them to start with, they were both tight and we gapped them according to the manual, intake .10, exhaust .18 if I remember right. I'm guessing it slipped after I kicked it over several times. and last fall he kicked it over trying to start it for about 30 minutes. No winterization either, I was trying to teach him good motorcycle maintenance procedures, and when we thought we were done thats when this happened

Well the best I've come up with so far is that the timing chain slipped or broke and a valve is now down when it should be up, so wish us luck and post your best references for online parts for a topend rebuild

I helped my fiend with his xs400 special II, with spring maintenance. last fall he parked his bike after it wouldn't start in later october. We speculated that is was the carbs, I took them off and soaked the in carb cleaner, cleaned out the jets, installed new needle's and gaskets. Proceeded to adjust the valves as per the manual, exhaust .018 and intake .010, changed the oil and filter, prefilled the filter before installation and new plugs. After we got everthing installed and torqued, fill the gas tank with fresh fuel. We noticed the battey is dead as a doornail. So instead of waiting for the battery t charge I decide to start kicking it over, after about 10 kicks it seizes just after TDC on the right cylinder. I manually turn the motor over backwards hal a revolution and it stops. Not sure if I should look in the top end or bottom any I deas would help

FWIW those type of batteries are notoriously short lived, and with the odds of putting a bike on its side its better to pay the $20 dollars extra and get a sealed type battery. Safer for the internals of your bike and it will last a lot longer than one that you have to fill and charge.