My KLR Shock Post;
The stock shock is a budget emulsion design without hardened internals. It also has inadequate compression damping and springrate for the majority of KLR riders. The 2014.5 and up bikes have stiffer springs and damping but still maintain the 1980 emulsion design.
The problem with the stock shock is that the combination of the soft body and emulsion design means that under hard or long term use the oil turns to a nitrogen entrained mess contaminated with aluminum wear particles (grey foamy sludge) and the damping goes to crap.
Many people put heavier springs on the stock shock and while that helps set the sag properly (which is necessary, read: Suspension and Springs
) the stiffer spring overwhelms the already weak compression damping making the shock "pogo" and the damping situation even worse…particularly as the shock degrades.
Raising links are an option if your tall enough; the shorter links decrease leverage on the shock which effectively increases both springrate and damping. You still have the quality issues with the stock shock and the effect isn't adjustable (without changing links) but it's something to try for those on a budget.
The best solution is a quality aftermarket DeCarbon shock. There are many shocks available; Progressive, Touratech, Ricor, Cogent, Elka, etc. ....they range from $379.00 to $1000.00 plus. For reference a stock Kawi shock is around $800 from the dealer. The best value IMO is Cogent's Adventure; it's a high quality shock, hardened body, DeCarbon design, deflective disk damping and an Ohlins spring. www.motocd.com
I have the full Cogent set up (DDC's and springs up front and an Adventure and Moab on the rear ) of my two Gen1's and the difference in performance and capability is massive. Easily the most drastic functional change of the 50+ mods I've done to my bikes.