Why do wave cams break?
Most people NEVER break their wave cams. But if the mechanism is tightened too much, they may crack, thereby saving the rest of the truck mechanism. Wave cams are the "sacrificial" component, meant to fail-safely so that the rest of the truck remains in tact. Wave cams are inexpensive and easily replaced.
One way to crack wave cams is to overly tighten the kingpin. When we re-designed the springs, everything got much better, but some "old" kingpins were either a little too short or had a couple too many threads. No worries, here's how to tune those perfectly. Lay the board on the ground, wheels side up then carefully push down on one wheel to see if the aluminum hanger reaches the baseplate before it "stops moving easily". If aluminum hanger doesn't make contact with the aluminum baseplate, it's a little too tight. Don't "force it". If so, please loosen up the black kingpin with a hex tool until the aluminum hanger can make contact with the aluminum baseplate, but no further. That's tuned right.
The other most common way to crack wave cams is to drop (or slam) the board down hard onto the ground. Please don't drop your board. HST Trucks are designed for carving not jumping or banging onto the ground.
HST Trucks are not designed to withstand slamming down hard on the ground, like at the end of this nose "manual".
- New in 2019 we introduced the Moly Washers which replaced the metal washers.
- New in 2020 we introduced the Moly Cams that self-lubricate and fit much better.
- New in 2021 are the second generation 85mm Black Kingpins which are 3mm longer and have a dab of nylon lock on the threads.
- New in 2022 we introduced the Dual Moly Washers which replaced the single moly washers (from 2019) with separate washers for the top and bottom of the springs. These fit better and reduce friction on the springs.
If you have these three recent innovations inside your HST trucks, they're approaching "fool proof". (It's a journey.)
These huge boards and huge trucks are heavy, but they're not able to withstand being pounded relentlessly. If you do this, you should get extra sets of wave cams and check them regularly.
The HST Truck is a simple mechanism and the loads inside the components are enormous. The springs are rated to 650 to 750 lbs axial load, and that force is translated to the wheels which give 20 to 25 lbs of restorative force. The mechanical advantage of this system is almost 30X multiplier, and the wave cam components are meant to be the sacrificial "fail safe" part that will break long before any of the metal parts break. They are relatively easy to replace and we recommend that if your trucks feel "wonky" please remove the kingpin and check your wave cams. If they're cracked or broken, please replace them.