timing?

[400man]

ok so i replaced the timing chain tensionor and while i was waiting i went ahead cleaned the air filter( it was pretty dirty) and cleaned up the head and valves. The exhaust valves were covered in carbon at least a 1/8 inch. now on to the timing i timed it according to the piston at tdc and the lobes facing all the way down with the marks on the cam sprocket horzontial with the head. started it up and it runs fine from idling to 1/2 throttle but then it just acts like you have the choke on all the way if you give it more. it runs and cuts out , on and on. whats the problem? is the timing off a tooth? does it need to be rejetted because i cleaned out the exhaust valves and tunnels, like its getting more in and out? also what timing mark on the fly wheel do you align to have correct timing theres the two single marks with about a 1/4 inch in between and then there are two more marks with little dashes beside them...thanks any help would be appreciated. (sorry for the long post this has me stumped)

[bwamos]

Could be off.

When setting the cam timing, did you have the chain slack on the front side of the motor or the tensioner side?

All slack should be on the tensioner side.


Not sure about the marks on the 400ex but the 300ex has 2 different ones. One is a || mark.. the other is a |T . On the 300ex you use the |T mark. I'm sure the 400ex is similar.