Tightening specs on axle/wheel nuts?

Trampa mtb with superstar hubs, ultimate trucks and 8” wheels.

So I’m used to tightening bolts down on my truck based off torque specs via the vehicle manual. If I tighten the nuts down too tight on my board the wheel won’t spin, if I go too loose I’m worried that it’ll fall off during the ride. What I ended up doing was going tight, then slowly loosening until I felt the wheel was free spinning on its own.

I know this is kind of a trivial question but I think it’s important to address it. Anybody have advice?

Ideally, if you are using correctly sized spacers or bearings that have built in spacers, and the wheel hubs are sized properly, you should be able to tighten your nuts down all the way (extremely tight), and still have your wheels spin freely with little to 0 horizontal play between the hubs and bearings.

As this isn’t always the case, I have found a good middle ground for me is to tighten your nuts all the way and back off just until the wheels spin freely as you mention you do.


My cheapo board has spacers between the bearings too.

I destroyed a bones ceramic bearing due to shitty evolve AT hubs not being very precise in measurement.

I just threw a speed ring in with the spacer to fill the gap and all good!

@Taliesin Nuts used on skate trucks have a nyloc (nylon?) ring inside the nut, this locks the nut on, not the torque you tightened it with. After you take them on/off a bunch of times they no longer lock as well so replace them periodically if you are regularly taking the wheels on/off.

Past that tighten them as much as you can to eliminate any lateral play but still allows them to spin freely.

Standard skate bearing spacers are not the best so I get my spacers from here: http://www.aluminumspacers.com/spacers-by-hole-size/hole-for-5-16-inch-bolts/as50-16-405

The thicker wall with 1/2" OD fits perfectly on the inner bearing race and they work very well. I can lock my Abec11’s down tight and they spin like crazy.


@namasaki do you know if the ones you linked will fit on the trampa ultimate truck axles? (Trampa Abec 5s and superstar hubs)

Thanks @Namasaki :+1:! Followed your advice. I just ordered two sets .405 for my builds from Aluminum Spacers


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.405 works on Abec11 flywheels. To make sure, add speed washers to your spacer in between the bearings until you can tighten it down tight and still spin the wheel freely. Then take the spacer and washers out and measure them together with calipers and order the closest size available, rounding up. For example, if you measure.400. Get .405 not .395

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There are probably TWO best ways to tighten a wheel nut (axel nut), and it depends on whether you use a spacer or not.

If you do use a spacer, tighten the nut firmly. A free wheel will spin a few revolutions quietly and then stop. This is perfectly in order.

If you don’t use spacers you will have to leave a tiny play between the bearing and the nut. A free wheel will spin for a long time before stopping. This might seem good but is actually not ideal.

I follow the rules above and I’ll try to explain why below for the interested.

First of, a spacer, for those unfamiliar with the term, is a metal tube mounted in between the two bearings of each wheel. The spacer has two purposes, (1) it keeps the two bearings perfectly parallel and (2) keeps the inner and outer ring of each individual bearing in line. It does so by ensuring no other part of the bearing but the inner ring is under pressure. Same purpose as the speed rings you mount on each side of the wheel.

Any gap (play) between the nut and the bearing could potentially cause the nut to loosen, the wheel to tilt and you to be less in control of the board. I think the gap also causes the wheels to revolve a little slower once you are on the board. Any movement not in the spin direction means loss of energy. Many of those drawbacks are minor and probably don’t happen very often. But they nevertheless exist.

Not using spacers nor leaving a gap means the bearing balls are likely under stress which causes unnessecary friction. (The nut will extert a force on the inner ring of the bearing towards the center of the board, while the wheel exterts a force on the outer ring on the other side of the bearing and in the opposite direction.)

Testing a bearing by letting a wheel spin freely only makes sense if you use spacers and have tightened the bolt. It won’t spin for very long because bearings rarely do. However, they should be somewhat quiet.

Counting spins on a wheel with play doesn’t make any sense to me. The bearing balls can be squared on such a wheel and the wheel would still spin. It is the inner ring spinning around the truck axle. The second you stand on the board that wheel is stuck. That’s because with your weight there is a lot of friction between the axle and the inner ring, hence the need of a bearing in the first place.