As for a chain, just find a quality brand like EK, DID, Regina, RK, etc... I've been happy with DID, EK and RK brands lately for my Zilla. 

Remember if you are replacing your chain, you should replace both sprockets too.  If you don't, your new chain will 'wear' / 'stretch' to match the condition of the sprockets quickly.

I'm not sure if Shawn is still building these,

http://www.suzukiquadracerhq.com/index.php?action=store;sa=view;id=29

Run a HD case saver for a little more added protection against case breaks.

I'm not sure if Shawn is still building these,

http://www.suzukiquadracerhq.com/index.php?action=store;sa=view;id=29

Run a HD case saver for a little more added protection against case breaks.

I believe his is an 85 so not sure that case saver will fit.

As rogue 1970 said install  new sprockets  at the same time.  I run a  did atv x ring  chain(  i think fancy term for o ring  chain) , on both my 85 lt250r  and my sons 86 lt230 quadsport wraped around vortex  sprockets. . I have adjusted it twice in the first 16 hours  of ride time . I haven't  touched it since. 40 hours  on them now.  We run them very hard too.

FYI... chain stretch is a common term, but really it is your chain 'growing'  The pins and bushings inside the chain itself wear and that is what makes the chain become longer.

Like I said before, just make sure to buy a good quality sealed chain (O,D,X.W,etc...) and regular maintenance will yield the longest life..... also replace the chain & sprockets as a set.  Also, don't just depend on WD-40 to 'lube' your chain.   WD-40 refers to Water Displacement version 40.... good for getting water out of the chain, but doesn't have lubricating oil required by chains.

Like Throttle Therapy said, just watch new chains that are installed and keep it adjusted to specs.

Measure 21 pins on the chain.  It should not be > 319.4mm / 12.57"

Chain Slack - 25-30mm / 1.0 - 1.2" between sprockets

Good Luck.

Sorry, I'm sure I saw something like a d and w type o-ring chain, but there are mostly 'O' and 'X' ring chains.

The 'O' ring chain, likes its name looks like an 'o' when viewing it from the side. 
The 'X' ring chain is another type of sealed chain.  When viewing it from the side looks like an 'x'.



The idea behind the 'x' ring is that it has two smaller surfaces that contact the plates and provides less drag then the o-ring chain.  I've read articles that tested the o-ring chains and while they do drag more (not very much) then a non-sealed chain when cold, once the vehicle is run for a few minutes, the chain comes up to operating temperature and it is as good as or better then the non-sealed chain.

lol, no problem.  I've already spent the money and made lots of mistakes along the way.  I hate learning this way, but it sinks in that way I guess

I just asked a guy this the other day and the conclusion of my advising senior men is that sealed is the only way and check tesile strength and if you buy a gold chain it's there better level of performance ... They concluded that there is so many choices out now who can try them all??? They had me buy EK gold Xring with a tensile strength of 8050lbs it cost me around $116 for 130 links of 520 because I have a plus six swinger and a OEM is I think 92 links? I hope this helps and I almost bought the 3-D chain lol twice as much money just for cosmetics ...

Tensil strength refers to how much of a load can be applied before it breaks?

Is it measured in pounds?