Suzuki 2 Strokes

On my 77 gt380 engine that I rebuilt a year ago,rebuilt crank and replaced nylon points drive gear,I aligned the crank timing marks,but when I put points cam in,the timing mark would not match up,it falls on a gear tooth so I went advanced,but to get proper timing I had to close points gap a little because plate was retarded all the way.So last week I replaced points and put points cam on retarded side of tooth,now I have proper timing but the plate is advanced all the way,no matter what I do I can not get timing plate in the middle of the slots,so am I doing something wrong or is the keyway in the nylon gear off a little?

Those "timing" marks are really only intended as assembly marks, to show that the timing gear and points cam have been put on the right way ... it just so happens that for most 380s, the markings are also close enough to the correct timing setting. So don't worry if things don't line up just so: they very rarely do.

What brand of points are you using, Nippon Denso or Daichi? Daichi is the usual aftermarket brand, and the fiber 'heel' on those is a bit too long, which often means you have to move the points plate all the way and juggle the points gap to get the timing dialled in. Don't worry about adjusting the points gap to get the timing right - as long as it's in the 0.3 - 0.4mm (12 to 16 thou) range, it's fine.

If you haven't done so yet, I would strongly recommend checking the ignition timing using a dial gauge. You will then know exactly how accurate your 'timing marks' are, and you will also have a reference that you can then use a strobe light to set the timing in future.

Thanks for the reply,using denso points,I set timing using dial gauge,the bike runs good the way it is set,so I will just keep it the way it is.

Agreed, if you've already set the timing by dial gauge, then you know exactly what's happening where it matters