just purchased a 1983 wr 430, needs new piston, help and advice welcomed!

12

You can get a new Wossner for it from Phillip at www.husqvarna-parts.com. You are going to love that when you ride it

take the top end to a reputable machine shop be fore you buy anything and see if it needs a bore..they will measure it up and depending on that will tell you what piston size needs ordered..

and i second the wossner...many have had good results with them

yes your gona love that one 430s where killer motors IF it needs bored you need too take REAL lite cuts the tooling bounces when it passes over a port better yet use a ridge hone iv been having a lot of trouble with this lately so after some research it seem that the ridge hone is the way to go on a two stroke and after seeing what whet iv seen [ long expensive story i wont bore you] i BELIEVE IT hone that sucker

There are a few of things to look for here.

1. Have a good look at the liner - where the middle M6 hole from the reed block is. Often, people install a screw here which touches (and cracks) the cylinder liner.
2. If the liner is out (from 86.0mm std.) to 87.5mm and worn, get a liner made that is 82.5mm and use the standard 400 L/C piston. You will then never run out of oversizes!
3. Make sure that whoever bores your cylinder does NOT bore it on the tight side - it will seize.
4. If you struggle to get it to run well - consider a new ignition, as this seems to be a common theme. Go for an Electrex unit, as they give a spark from about 200 revs - which helps with starting...

Great bikes though - a popular choice from Clubman to Expert!

Andy Elliott. (www.hva-factory.com)