Kart rim modifications

So I was talking to a guy recently who cuts off (shortens) his bolts that go threw his rims to help hold the tires on, and he uses epoxy on the threads to prevent any air leaks. Said he does this on both his 4 stroke (lo206) and 2 stroke (X30) chassis’.

Is this a common thing? My tires are always leaking air, so I’m tempted provided its a safe thing to do. Not sure if throwing tires off the bead in corners would be regular issue?

I suppose it depends what kind of pressure you’re running. I mean, here it’s pretty unheard of to throw a tyre but we run at 1 bar ish. I’ve often thought those screws are pretty useless, they never leak though - I try to put new seals on them each tyre change.

Karts ran for decades without retaining screws in the rims.
The supposed need for them has come about through the adoption of ‘bostik’ tyres with ultra short life running at ultra low pressures.
The use of these tyres has led to rib injuries and the further expense of rib protectors which are a recent requirement as well as the problems of tyre disposal and the cost.
Karts at all levels can run on tyres with a hardness above 60 Shore with no problems and with pressures around 20 psi there would be no need for bead retainers.

Seems like a lot of silly work to go through to lose the functionality of your beadlock wheels.

Running down at 7-8 psi on sticky tires and high horsepower, I would absolutely say beadlocks are necessary. I’ve seen karts debead tires in the right scenario, or partially debead a tire that causes a lot of air loss. That said, above 10 psi you’re probably at a very low risk of debeading a tire.

If your wheels are leaking, it’s probably one of these two things:

  1. Damaged o-rings on beadlocks causing poor seal. Always slightly wet or lubricate the o-rings before installing, and make sure you’re not over-tightening and crushing and damaging the o-ring.
  2. Loose or damaged valve stem core. Double-check your valve stem core is tight with a the little wrench. If it’s tight and still leaking, it isn’t uncommon for them to go bad and stop sealing properly, so you can just pop a new one in there.

Both are two minute fixes that cost a penny, and don’t require you to alter the functionality of the wheel.

Spritz a little soapy water on that wheel and see if you can pinpoint the leak. I spray water on the beadlocks every time I mount tires to check.

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I’ve also had certain wheels where the tire is prone to receding back from the edge of the rim after beading up the tire and releasing the air. This causes a slow air leak on the outer edge of the tire/rim. To prevent this I now screw in two of the three bead lock screws completely before removing the third in order to release the pressure after beading up the tire.

I did on my practice rim set. I changed so mange tires on that rim set, the thread is gone and I have taped to the bigger size. No really other choices for me.

TJ and Evan nailed it. Good valve stems, fresh O-Rings, and bead the tire good. All the above being done will eliminate 99% of leaks.

Sometimes a tire bead can be out of round causing a leak and sometimes a pore can open in the magnesium, but those are pretty rare occurances.

I’ve tracked my leaks (All my leaks) down to the retaining screws. Every single one of my rims leak from that area. Even my brand new Douglas rims right out of box are all leaking.

Its frustrating.

Didn’t realize they sold o-ring replacements for those retaiing screws, I’ll look into that.

Yes, replace the o-rings every time. We have a pack of a hundred and throw them away every time. This is an o-ring seal, not a thread seal. Very big difference. If you have a leak there it is the o-rings fault, not the threads or the screw.

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Recommend replacing the Douglas Allen head screws with screws similar to OTK that requires no tool.

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Where did you get the o rings from

I ordered Viton o-rings for the bead locks and they have a significantly better life, and are still very inexpensive. They don’t chafe near as bad, and don’t dry out like the standard rubber. Still recommend replacing fairly often, but definitely an improvement.