440EX Timing Problem

[Dew2008]

Got a timing problem. I have the T mark alligned but when we adjusted the cam we can not get the lines dead even - - One side will be down and other up, So we move them one tooth and it does the opposite other side up and this side down. What are we missing??? Stage 2 Hot cam no decompressioner, 440 bore, I am not sure what the problem is but its giving us a fit. Please help me out ASAP!!!! Thanks in advance.


We have tried doing this multiple times and just get it exactly right. Could this be from wear? I am not to happy with the idea of putting it back together and having to re-do it again. I just need to know if we are missing something or doing it wrong?

[dustin_j]

I just went through the same thing on my 400. I found that the marks were slightly off, but when I moved one tooth to compensate it was worse. Thus, I put it on the closer of the two. The marks were only minimally off and shouldn't bother anything. Make sure you let the tensioner go and verify it is lined up the same, since the cam gear rotates toward the rear of the quad when the tensioner is on. That's the best advice I have.

I was reading some of your other threads, and I do not understand how your worn rockers would have caused your quad to jump timing. Did they actually cause the cam chain to jump, or did they incorrectly move valves?

[Dew2008]

It allowed the back of the cam to come up allowing slack on the on timing chain causing it too jump.

[Dew2008]

#1 How do I find if I am on the compression stroke being that my cam is out of time? I can't judge it by the rockers because I am out of time. Anyone?

#2 Any other suggestions? I am getting backfire out of the carb. This is really discouraging me with this quad. I am getting to the point to where I just want it out of my hair. I love this quad but its getting on my last nerve.


PLEASE HELP!!!

[Dew2008]

Wow you guys are so damn helpfull here. I figured out the marks, my chain was slacked so I replaced it with a HD chain and it straightend out.

I now need to know how to find the compression stroke with the cam out of time. Any suggestions???

[GPracer2500]

The position of the cam is the only thing that distinguishes the compression TDC and the exhaust TDC. To set the timing, all you need to do is get the piston to TDC and then line up the cam using the marks on the cam gear. If you line it up with the lobes facing down you've just established the compression stroke. If you align it with the lobes up you've just established the exhaust stroke.

Follow? If not then just 1) remove the cam altogether. 2) Get the piston to TDC. 3) Install the cam with the with the cam marks lined up and the lobes facing down (don't move the crank while you're doing that--just move the cam alone as needed). 4) You're now in time with the piston on the compression stroke TDC.

Note: You can install the cam with the lobes facing UP and the cam marks aligned. You will still be in time if you do this. The only difference is now you're on the exhaust stroke TDC instead of the compression stroke TDC. This is ok but it adds the extra step of rotating the crank 360deg so you can bolt the valve cover back on without compressing valve springs at the same time.