MXC Repair

If you’ve ever lost a wheel due to loose lug nuts you know it’s typically trashed, worst is when it’s an expensive MXC. I had the chance to fix a second one of these after a fellow racer lost his wheel last weekend. Just wanted to show you guys what I do to fix it. You can ask @fatboy1dh on how his has been holding up over the years as well.

Start:

First step, setup in lathe to face mounting surface and bore. I ensure the wheel bead is concentric within .001” before starting to cut.

I only take about .005” off of the mounting surface to not reduce any strength, it it mainly to make sure it is flat, the additional dings in it wont effect how it works. I also bore the hub as they tend to get egg-shaped when they are loose.

Next I set it up in the Mill to drill the holes out to remove the oval shape damage.

Then I just fire up my CNC lathe to make 3 bushings that will press fit into the new holes

Then press the bushings in place, ready to mount back up.

Note I keep the end of the spacer down about .02” from the mounting surface so it will always be pressing the wheel to the hub.

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I actually forgot about this. I have literally used this wheel 100x since then. No issues at all. Luckily, I have not left the lug nuts loose again since then…

This is great, however, I would venture to guess most of us don’t have a lathe or mill to do this ourselves, so I guess you’re the go-to guy for wheel repairs now!

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Very nice work… makes me wish I had machine access still. Just a thought – Instead of press-fit bushings, I’d be inclined to re-machine 3 OEM-sized holes indexed 60° from the originals… Ensures full flange contact then. The ‘old’ holes could be left large as ‘weight reduction’….lol

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Great stuff Matt, I’ve trashed a wheel because of this in the past.

Now the million dollar question: How can we repair and true bent MXC wheels??

Yeah I had thought of that as well, for me though I did not have access to long rear tools that would need to go 6”+ down in to spot face it. The bushings were what i’m able to do with my existing tooling.

Haha that is less likely, but i’m happy to hit them with a dead blow to see what happens

Perhaps face the ‘mating’ surface on the front in the lathe for cleanup, and don’t worry about spot facing?

Then flip it over and do thru holes from the backside….thru hole won’t care.

To true the bent ones, I wonder if you pressed on ‘high’ side of mating surface while wheel is sitting ‘inverted’ (rim lip on surface) with a hydraulic press…..VERY carefully. Spun > cast for this operation….