Bouncing Back

QHow do I know if I’ve refilled my shocks properly? I’ve heard the shaft should pop back out after you compress the shock. Is that true? How far?

AThe amount that the shock shafts “pop out” after being compressed is called “rebound,” and to be clear we’re talking about compressing the shocks with the springs removed. The amount of rebound depends on the amount of oil in the shock. First and foremost, you want to be sure you don’t have too much oil. It’ll be obvious if you do, because you won’t be able to compress the shock shaft fully (or, it will be hard to compress fully, then shoot back out quickly when released). If you run the shocks with too much oil in them, you’ll either pop the cap off or blow out the shock seals. If overfilled, just loosen the shock cap and compress the shaft, then tighten it when the shaft is about 5mm of fully compressed. The shaft should now compress fully and easily, then rebound slightly. Racers can obsess over this, painstakingly making certain each shock rebounds the same amount, but if you’re just fun running it’s hardly worth worrying about.

Right: Losi’s Shock Matching Tool (LOSA99170, $35) makes it easy to match your shocks' damping.

Above: If you can’t fully compress the shock, it has too much oil inside of it.

Left: To bleed the shock, loosen the cap and compress the shock shaft. Do this over a towel to catch the oil that bleeds out.