Valves are 900 and 1000 the same??

Well heres the story part 2. I found out the valves I got to replaced the bent one2 I had were also bent (never take anthing for granted) so I know have them replace with good ones. Also with the right keepers.So I got all back together again(again and again and again sorry flash back)I now am having a VERY hard time getting it started It seems to be kicking back a littlebit when I crankin it over,after a lot of crankin it may or may not fire up. If it does fire up it seems to run ok not perfict but not terrible(I don't have the air box hooked up yet) So I'm at a stand still as I don't know what to do next. Could the cams still be a little out or???????????Any ideas would be VERY helpfull.Thank you all again signed Descouraged:S