URGENT! engine won't start

[flattracker4389]

i have a really important question. i just got my bike rebuilt. its a 416 now and its got the 11:1 compression. i put my motor back together and im pretty sure i have my timing lined up. i put the carb, gas tank and airbox back on. when i try to crank it without the lid it sounds like somone gasping for air. with the lid on its sounds normal. but still doesnt start. i am goin to try to test my spark plug tomorro but have any of yall ran into this problem before? yall have any suggestions

[the Z Man]

Turn on the gas,,,:D

[flattracker4389]

the gas is on. i tried it in on and res neither work

[Aceman]

Originally posted by flattracker4389
i put my motor back together and im pretty sure i have my timing lined up.

I bet that is your problem right there. Did you have the piston at TDC when you timed it. Cam with lobes down and cam sprocket marks where they should be (I can't remember which way they go or I would tell you). If it's alright, check spark, fuel, air, etc. The only reason I think it would be timing is that it sounds like your piston is going through it's stroke when your valves are opening and closing. Hence the gasping for air sound. Valves should be opening and closing around the top and bottom of the strokes, not in the middle.

[flattracker4389]

hey yall i double checked my timing and changed spark plugs n its runnin like a bat out of hell now lol thanks for the help, this was my 1st rebuild. i'll be back if i need any more help. thanks

[cals400ex]

Originally posted by flattracker4389
the gas is on. i tried it in on and res neither work


well i guess your last resort is to try it in the off position. :p

just kidding. glad you got her running.

[exrider360]

im guessing your timing is off becase we just rebuilt my frineds 400 last night with a high comp piston and it started right up i bet it is your timeing