putting the 400ex back together

[YFZWHEELIER]

ok well i just got my head back today and i put everything back on and it wont fires, its like its not gettin spark, the plug is good tho. i think it is my timing. i have no clue on how to time it and what top dead center mean, could some one help me out please?
thanks a lot

[honduh440]

STOP! leave the bike alone and take it to a shop! i promise you will hurt it more if you continue to mess with internal parts. I see you are from kansas if your anywhere close to wichita have N motion put the quad back together their number is 316-262-8900

[YFZWHEELIER]

hey screw u buddy, im not takin it to a shop and payin 500 for them to time it, im just asking how u time it, i know quite a bit about quads im just not a mechanic so CHILL OUT MAN

[chucked]

if its out of time it will still spark, just not at the right time, check for spark.

[I-7]

Originally posted by YFZWHEELIER
ok well i just got my head back today and i put everything back on and it wont fires, its like its not gettin spark, the plug is good tho. i think it is my timing. i have no clue on how to time it and what top dead center mean, could some one help me out please?
thanks a lot


The notches should line up for top dead center but it will still spark even if the timing is not lined up. Retrace your steps to see where you went wrong or seriously consider honduh440s advice and take it to a professional shop to insure that you dont do any major damage that your will later regret...

[440ex2001]

to time it take off the big allan head screw on the left hand side of the engine. There is another smaller allan head screw above it and to the left. Put a ratchet on the crank shaft turn it counter clock wise until you see a t line it up with the line on the case(you'll know what Imtalking about when you do this) come up in the little peep hole. Take the valve cover and head off. Take off the timing chain tentioner. Remove the cam bearing keepers. remove cam bearings. Remove chain from cam.There are 2 lines on the cam gear. Make sure they are lined up level with the head /vale cover mating surface. Put on the timing chain do the opposite for reassembly. make sure you dont hit the starter or move the crank. Hope this helps.

[balls2da-wall]

my sugguestion would be to by a manual for the 400ex for around 25$...tells how to time the engine along with everything else on the 400ex....helped me out a ton when I rebuilt my engine and I was just 16 when I did it....timing is no big thing...its pretty simple.

[YFZWHEELIER]

Originally posted by 440ex2001
to time it take off the big allan head screw on the left hand side of the engine. There is another smaller allan head screw above it and to the left. Put a ratchet on the crank shaft turn it counter clock wise until you see a t line it up with the line on the case(you'll know what Imtalking about when you do this) come up in the little peep hole. Take the valve cover and head off. Take off the timing chain tentioner. Remove the cam bearing keepers. remove cam bearings. Remove chain from cam.There are 2 lines on the cam gear. Make sure they are lined up level with the head /vale cover mating surface. Put on the timing chain do the opposite for reassembly. make sure you dont hit the starter or move the crank. Hope this helps.

what are the cam bearing keepers? i do not see them aand i dont reemmber taking them off when i took the cam out the first time...does n e one have pics of it

[440ex2001]

they are about an inch long hollow pegs that you have to pull out of the head. They should be on each side of the cam beside the bearings.

[free_rider20]

After I got my 400 back together i had the same problem. I had spark and I was almost positive It was timed right. i tried hooking up a car battery for extra juice but it didnt help. We had to pull start it behind a truck to get it goin but since then it starts fine.

[honduh440]

Originally posted by YFZWHEELIER
hey screw u buddy, im not takin it to a shop and payin 500 for them to time it, im just asking how u time it, i know quite a bit about quads im just not a mechanic so CHILL OUT MAN



actually it would only cost you abotu 100 dollars for them to do it if not less and if you dont know what TOP DEAD CENTER or what the cam bearing keepers are then i would say honestly take it to the shop. im not being an ***** to you by any means ive seen people destroy their cams and rocker arms by a mistake like this and it will cost you more like 700 bucks if you mess it up

[mojoe2878]

Originally posted by honduh440
actually it would only cost you abotu 100 dollars for them to do it if not less and if you dont know what TOP DEAD CENTER or what the cam bearing keepers are then i would say honestly take it to the shop. im not being an ***** to you by any means ive seen people destroy their cams and rocker arms by a mistake like this and it will cost you more like 700 bucks if you mess it up
not to mention destroying the piston, valves and the whole head when its timed wrong and the piston hits the valves.

[440ex2001]

Its not rocket science guys. Get a manual and follow the directions 3 months ago I didnt own a 400ex now I can tear it down to the crank case and back up i 1 1/2 hours.