Timming a yz426 with 450 ex cam?help

[yfz3x]

just checking my vlave clearences today,and i got all the marks

lined up on the fly wheel and the 2 punch marks line up on

cylinder edge on the intake cam but the exhaust cam puch mark

doesnt line up with the cylinder edge. i wound have to move the

cam 2 teeth counter clockwise for the mark to line up.so only

moved it 1 tooth back to see if that works better but it back fires

bad on deceleration
i think it has the yz 450 cam with the auto decomp i didnt know if theres a differnt way to time the exh cam or should that puch mark be definatly inline with the cylinder edge?
oh and i did notice the ex cam teeth are worn and rounded pretty good too if that helps
any help would great thanks

[ss440ex]

You should have mark the position of the exhaust cam before you removed it...

See if this will help,
On the 450 ex cam forget about the timing dots.
Time the crank and intake cam.
On the R/H side of the engine, note the position of the intake cam lobe!
The front cam(exhaust cam) must mirrow reflect that.
The intake should be around the 10 o-clock position.
The exhaust should be around the 2 o-clock position.

ALWAYS hand crank the engine over first,

Hope this will help..
Also try thumpertalk.com do a search.

Good luck, you`ll get it.
Once you get it timed, mark the exhaust cam R/H lobe for future ref. Scribe a line into the cam holder.

[yfz3x]

i did mark it before i moved it,just so i knew that i only moved it 1 tooth, and i did notice that the exh cam lobe is definatly deffernt than the intake cam its about 2 teeth and the lobe would be the same,
but when i moved it 1 tooth towards the way it should be it ran worse than the way it was before (when it was 2 teeth off)
by me moving it closer to the real spot shouknt it run better?
thanks al

[ss440ex]

Are you checking the lobe postion with the cam chain tensioner installed.
That will also make a difference.