With the help of people on this forum, I have finally got my 1975 (US spec) 400/4 running reliably. That process involved replacing points, condensers, carb/jets rebuilt/replacement and attempting to get the timing right. Also having a defective spark plug prolonged this process as I only checked the plugs after doing all the other work mentioned.
I do though have another issue. There are some very pronounced vibrations at around 3500 rpm then again at higher revs - so they not there throughout the rev range, which I hope is a positive sign!. They are pretty bad though and have been around since the engine rebuild I completed this time last year. I thought they would disappear when I got her running correctly. A friend said it could be a timing issue. Anyone had this problem and found a solution?
Thanks
